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BoP Lab / Buttonwillow Raceway Park

T1 + T4 + SM + HP at Buttonwillow Raceway Park

No mapCal Club 2024, Cal Club 2023

Track map: sectors and speed trap

Track map with timing sectors and speed trap
Shown for: Cal Club 2026 (practice, qualifying, race) · Cal Club 2025 (practice, qualifying, race)
Class · click a class to switch, + to compare alongside
Track configuration
Events

This track has been raced on 4 configurations (The Circuit, 2.57 mi; 2.92 mi; 1.83 mi; 3.02 mi). Laps on different configurations are not comparable, so only events on the 2.57 mile layout are shown; switch above to see the others.

One session is left out because the timing does not look like full laps: Cal Club 2023 Qualifying #2.

One run is left out as not that car's own laps (far quicker than the car managed in any other session and than anyone else in its class all week; usually a swapped transponder): William Rasmussen in Cal Club 2025 Fri PM (1:36.912; the car's best in any other session was 2:00.848 and the rest of the class's best all week 1:41.720).

PosCarDriverClass#LapTheoreticalQualRace5-lap stintConsistencyTrapS1S2S3
1MG MidgetBill OkellHP71:40.295 B-P1:40.2612:07.503 B-Q12:04.195 A-R22:04.781 A-R2+2.144 A-R2116.4 B-P27.543 B-P28.857 B-P43.861 B-P
2Mazda Miata (1993)John StottSM451:41.720 B-P1:41.5472:04.563 B-Q13:19.168 B-R1153.3 B-P28.011 B-P29.514 B-P44.022 B-P
3BMW M3Ian BarberiT1741:46.465 B-Q21:46.0661:46.465 B-Q21:47.434 B-R11:47.873 B-R1+0.605 B-R1114.9 B-Q2, B-R228.992 B-Q230.811 B-P46.263 B-Q1
4BMW M4 GT4Drew DelmonicoT1431:47.084 B-Q11:46.3161:47.084 B-Q11:47.467 B-R11:48.228 B-R1+1.310 B-R1161.4 B-P29.150 B-Q230.850 B-R146.316 B-P
5Mazda Miata (1999)Alan Leukhardt IIISM171:51.297 B-P1:50.8002:06.617 B-Q12:07.598 B-R12:08.347 B-R1+2.314 B-R1120.9 A-Q130.402 B-P32.034 B-P48.364 B-P
6Mazda Miata (1999)Sophia StoreySM65, 1871:53.207 B-P1:52.8252:02.978 B-Q12:02.546 B-R12:02.991 B-R1+1.086 B-R1102.6 B-R130.832 B-P32.705 B-P49.288 B-P
7Mazda Miata (1999)Curtis ZhiSM771:53.375 B-P1:53.3752:02.880 B-Q22:02.884 B-R12:03.224 B-R1+0.505 B-R1102.2 B-Q233.066 B-R135.129 B-Q154.444 B-R1
8Mazda MX-5Oscar JacksonT4161, 161x1:58.339 B-Q11:58.3391:58.339 B-Q11:59.922 B-R12:01.033 B-R1+2.860 B-R1105.5 B-Q132.394 B-Q134.071 B-Q151.874 B-Q1
9Pontiac GTOEd GlessT1431:59.123 A-R11:58.3401:59.760 A-Q21:59.123 A-R12:00.018 A-R2+1.331 A-R2120.7 A-Q132.383 A-R134.587 A-R251.370 A-R2
10Ford MustangPratt ColeT181:59.261 B-R21:58.8621:59.261 B-R22:01.195 B-R2+2.608 B-R298.6 B-R232.624 B-R234.661 B-R251.577 B-R2
11Mazda Miata (1991)William Wallis >115%SM1962:00.831 B-Q22:00.6532:00.831 B-Q22:01.805 B-R12:02.063 B-R1+0.492 B-R1102.2 B-Q132.837 B-R134.577 B-Q253.239 B-Q2
12Mazda MiataWilliam Rasmussen 2+ cars >115%SM232:00.848 B-Q22:00.8482:00.848 B-Q22:01.937 B-R12:02.575 B-R1+1.131 B-R1102.9 B-R232.618 B-Q234.761 B-Q253.469 B-Q2
13Toyota FRSIzzy SanchezT4782:01.157 A-R12:00.4482:01.678 A-Q22:01.157 A-R12:02.239 A-R2+1.404 A-R2135.5 A-Q232.955 B-P34.751 A-R152.742 B-P
14Mazda MiataEvan Jacobs >115%SM352:01.305 B-Q22:00.8992:01.305 B-Q22:01.800 B-R22:02.068 B-R1+0.298 B-R1103.9 B-R232.898 B-R134.715 B-R153.286 B-Q2
15Mazda Miata (2003)Ryan Busk >115%SM72:01.392 A-Q22:01.3922:01.392 A-Q22:02.555 A-R22:02.854 A-R2+0.519 A-R2124.6 A-R233.152 A-R235.121 A-R253.594 A-Q2
16Mazda Miata (1999)Nathan Del Carmen >115%SM882:01.474 B-Q22:01.3882:01.474 B-Q22:01.948 B-R22:02.308 B-R2+1.139 B-R2101.3 B-R232.746 B-Q234.922 B-Q253.720 B-Q1
17Mazda Miata (1999)Nick Leverone >115%SM942:01.650 B-R12:01.2392:01.706 B-Q22:01.650 B-R12:02.204 B-R1+0.855 B-R1120.7 A-Q132.921 B-R234.741 B-Q253.577 B-Q2
18Mazda Miata (1991)Clement Lee >115%SM872:01.753 B-Q12:01.2872:01.753 B-Q12:01.777 B-R12:02.189 B-R1+0.579 B-R1101.4 B-R132.979 B-R134.807 B-R153.501 B-Q1
19Mazda Miatta (1999)William Rasmussen 2+ cars >115%SM232:01.816 A-Q22:01.8162:01.816 A-Q22:02.486 A-R22:02.695 A-R2+0.697 A-R2125.6 A-R233.179 A-R234.870 A-Q253.902 A-Q2
20Scion FR-STony KiratsousT435, 362:01.843 B-Q12:01.7862:01.843 B-Q12:03.865 A-R22:04.289 A-R2+0.751 A-R2133.6 A-R232.895 B-Q134.958 B-Q153.933 B-Q1
21Mazda Miata (1999)Tyler Vance >115%SM12:01.993 A-Q22:01.9932:01.993 A-Q22:03.785 A-R12:04.163 A-R1+0.882 A-R1119.9 A-R133.194 A-Q135.246 A-Q153.843 A-Q2
22Mazda Miata (2001)Wyatt Couch >115%SM662:02.169 A-Q22:02.1692:02.169 A-Q22:03.291 A-R22:03.392 A-R2+0.844 A-R2122.5 A-R233.243 A-Q235.205 A-Q253.822 A-Q2
23Mazda Miata (1999)Max Logemann >115%SM32:02.199 B-Q2sector data unreliable2:02.199 B-Q22:02.274 B-R12:03.047 B-R1+1.052 B-R1127.6 B-P26.21829.11843.340
24Mazda Miata (2003)Brett Revetta >115%SM482:02.373 B-Q12:02.2072:02.373 B-Q12:02.639 B-R22:03.104 B-R1+0.791 B-R1102.0 B-Q132.995 B-Q235.057 B-Q154.155 B-Q1
25Mazda Miata (1993)Alex Pollard >115%SM472:02.418 B-P2:02.4182:03.389 B-Q22:03.247 B-R22:04.086 B-R2+1.144 B-R2122.9 A-R133.102 B-R235.272 B-R154.482 B-Q2
26Mazda Miata (1999)Todd Launchbaugh >115%SM13, 732:02.731 B-Q22:02.4862:02.731 B-Q22:02.838 B-R12:03.815 B-R2+0.739 B-R2100.8 B-R133.200 B-R235.125 B-R254.161 B-R1
27Mazda MiataKristina EtheringtonT4962:03.007 A-R22:02.6462:03.241 A-Q22:03.007 A-R22:03.776 A-R2+1.019 A-R2128.1 A-Q233.464 A-Q235.459 A-R153.723 A-R2
28Mazda Miata (2003)Jeremy Rutter >115%SM372:03.024 A-Q22:02.7022:03.024 A-Q22:04.170 A-R22:04.257 A-R2+0.496 A-R2122.6 A-Q133.350 A-Q135.216 A-Q154.136 A-Q2
29MG MidgetLee Fleming >115%HP002:03.082 B-R12:00.4182:05.170 A-Q12:03.082 B-R12:04.295 A-R1+1.090 A-R1126.2 A-R230.556 A-Q135.463 B-R154.399 A-R1
30Mazda Miata (1999)David Mitchell >115%SM752:03.396 A-P2:03.3962:08.722 A-Q22:10.195 A-R22:11.410 A-R2+1.502 A-R2124.6 A-Q234.572 A-Q136.800 A-Q153.851 A-P
31MG MidgetBrian Linn >115%HP482:03.551 A-R12:03.2192:04.965 A-Q12:03.551 A-R12:04.243 A-R1+0.928 A-R1121.0 A-R133.172 A-R135.274 A-R154.773 A-R1
32Mazda Miata (2003)Jake Johnson >115%SM1512:03.918 A-Q22:03.6242:03.918 A-Q22:04.562 A-R22:05.101 A-R2+1.367 A-R2126.2 A-R133.473 A-Q235.575 A-Q254.576 A-Q2
33Mazda Miata (1993)Sam Rezai >115%SM1772:03.923 A-Q12:03.9102:03.923 A-Q12:05.864 A-R12:06.551 A-R1+1.027 A-R1127.3 A-Q133.474 A-Q135.897 A-Q154.539 A-Q1
34MG MidgetNoel Hayward >115%HP22:04.870 B-R22:04.7112:04.870 B-R22:10.679 B-R1+4.104 B-R199.2 B-R233.577 B-R236.471 B-R254.663 B-R2
35Mazda Miata (1999)Cooper Hicks >115%SM862:05.080 A-R12:04.7762:05.276 A-Q22:05.080 A-R12:05.643 A-R1+1.082 A-R1121.0 A-R133.780 A-R135.806 A-Q155.190 A-Q2
36Mazda Miata (1991)Hendrik Webster >115%SM972:05.607 A-Q22:04.6972:05.607 A-Q22:05.928 A-R22:06.497 A-R2+0.937 A-R2125.2 A-Q133.857 A-Q235.824 A-Q255.016 A-Q1
37Porsche BoxsterLynne GriffithsT4312:05.833 B-Q12:05.6142:05.833 B-Q12:07.226 B-R12:08.659 B-R1+3.459 B-R1122.0 A-Q133.699 B-R136.036 B-Q155.879 B-Q1
38Mazda RX-8Steven KiratsousT472:05.858 B-R22:04.8862:06.604 B-Q22:05.858 B-R22:06.907 B-R2+1.122 B-R2105.7 B-R233.416 B-R235.585 B-R255.885 B-R2
39Mazda Miata (2000)Nicholas Stewart >115%SM872:06.288 A-Q22:06.0282:06.288 A-Q22:07.124 A-R22:08.162 A-R2+1.541 A-R2123.1 A-P34.202 A-Q236.128 A-Q255.698 A-Q1
40Mazda Miata (1990)Sayo Haraishi >115%SM342:07.037 B-Q12:06.5012:07.037 B-Q12:08.275 B-R12:08.790 B-R1+1.938 B-R1100.2 B-Q134.243 B-Q136.262 B-Q155.996 B-Q1
41Mazda MiataKayla EtheringtonT4162:07.618 A-Q22:07.2572:07.618 A-Q22:08.317 A-R22:08.911 A-R2+1.372 A-R2124.3 A-Q234.878 A-R236.704 A-Q255.675 A-Q2
42Mazda Miata 0Preston Lewis >115%SM118, 102:07.663 A-R22:07.2012:08.505 A-Q22:07.663 A-R22:08.201 A-R2+1.310 A-R2125.2 A-R234.455 A-R236.398 A-R256.348 A-R2
43Toyota YarisBobby Beyer >115%HP182:08.224 B-R22:08.0102:10.927 B-Q12:08.224 B-R22:09.636 B-R2+2.098 B-R292.3 B-R234.660 B-R237.206 B-R256.144 B-R2
44Mazda Miata (2001)William Sturgeon >115%SM1182:08.519 A-Q12:08.1782:08.519 A-Q12:11.184 A-R22:11.810 A-R2+1.057 A-R2118.9 A-Q134.873 A-Q136.458 A-Q156.847 A-Q1
45Mini CooperTom Tuttle >115%HP422:09.238 B-R22:08.4162:11.042 B-Q12:09.238 B-R22:10.173 B-R1+1.249 B-R199.0 B-R234.631 B-R137.306 B-R156.479 B-R2
46Mazda MiataBill Nelson >115%SM1992:10.339 B-Q12:09.5822:10.339 B-Q12:11.321 B-R12:12.199 B-R1+2.275 B-R194.8 B-R235.256 B-R137.267 B-Q157.059 B-Q1
47Mazda Miata (1990)John Rice >115%SM202:11.974 A-Q22:11.6252:11.974 A-Q22:13.511 A-R12:14.141 A-R1+1.656 A-R1115.3 A-R235.615 A-Q237.635 A-Q258.375 A-Q2
48Mazda Miata (1990)Lauren Lewis >115%SM452:12.076 A-Q12:11.6882:12.076 A-Q12:12.821 A-R12:14.152 A-R1+2.986 A-R1112.2 A-R235.483 A-R137.835 A-Q158.370 A-Q1

One row per driver and car (a driver who changed cars has a row for each). Each cell is that driver's best in that car across the selected events, with the session it was set in. Best 5-lap stint is the mean of the driver's quickest five consecutive race laps, and consistency is how far their median race lap sat behind their best in that race (small is a driver who does it every lap); both come from the race with the best stint. The fastest in each column is purple, and a car whose best lap is more than 115% of the fastest in its class is greyed (marked ">115%" beside the driver) and left out of the colour scale. Click a column to sort, a row to highlight it. Theoretical lap is the sum of the best sectors, whichever laps they came from, and never slower than the best lap (where a car's fastest laps were recorded without sector times, its best lap is used). The 115% mark is about the car's best lap only: a car whose best lap is within 115% of the fastest in its class is never marked. Greyed sectors with no theoretical lap mean the sector times on file do not add up to a believable lap. Letters refer to the events above; Q is qualifying, R a race.

Sectors

Sectors are numbered in lap order from start/finish, whatever each event's timing called them; the loop names are SCCA timing's.

By car

CarClassDriversLapQualRaceTrapS1S2S3
MG MidgetHP41:40.295Bill Okell2:04.965Brian Linn2:03.082Lee Fleming126.2Lee Fleming27.543Bill Okell28.857Bill Okell43.861Bill Okell
Mazda MiataSM/T4321:41.720John Stott2:00.831William Wallis2:01.650Nick Leverone153.3John Stott26.218Max Logemann29.118Max Logemann43.340Max Logemann
BMW M3T111:46.465Ian Barberi1:46.465Ian Barberi1:47.434Ian Barberi114.9Ian Barberi28.992Ian Barberi30.811Ian Barberi46.263Ian Barberi
BMW M4 GT4T111:47.084Drew Delmonico1:47.084Drew Delmonico1:47.467Drew Delmonico161.4Drew Delmonico29.150Drew Delmonico30.850Drew Delmonico46.316Drew Delmonico
Mazda MX-5T411:58.339Oscar Jackson1:58.339Oscar Jackson1:59.922Oscar Jackson105.5Oscar Jackson32.394Oscar Jackson34.071Oscar Jackson51.874Oscar Jackson
Pontiac GTOT111:59.123Ed Gless1:59.760Ed Gless1:59.123Ed Gless120.7Ed Gless32.383Ed Gless34.587Ed Gless51.370Ed Gless
Ford MustangT111:59.261Pratt Cole1:59.261Pratt Cole98.6Pratt Cole32.624Pratt Cole34.661Pratt Cole51.577Pratt Cole
Toyota FRST412:01.157Izzy Sanchez2:01.678Izzy Sanchez2:01.157Izzy Sanchez135.5Izzy Sanchez32.955Izzy Sanchez34.751Izzy Sanchez52.742Izzy Sanchez
Mazda MiattaSM12:01.816William Rasmussen2:01.816William Rasmussen2:02.486William Rasmussen125.6William Rasmussen33.179William Rasmussen34.870William Rasmussen53.902William Rasmussen
Scion FR-ST412:01.843Tony Kiratsous2:01.843Tony Kiratsous2:03.865Tony Kiratsous133.6Tony Kiratsous32.895Tony Kiratsous34.958Tony Kiratsous53.933Tony Kiratsous
Porsche BoxsterT412:05.833Lynne Griffiths2:05.833Lynne Griffiths2:07.226Lynne Griffiths122.0Lynne Griffiths33.699Lynne Griffiths36.036Lynne Griffiths55.879Lynne Griffiths
Mazda RX-8T412:05.858Steven Kiratsous2:06.604Steven Kiratsous2:05.858Steven Kiratsous105.7Steven Kiratsous33.416Steven Kiratsous35.585Steven Kiratsous55.885Steven Kiratsous
Toyota YarisHP12:08.224Bobby Beyer2:10.927Bobby Beyer2:08.224Bobby Beyer92.3Bobby Beyer34.660Bobby Beyer37.206Bobby Beyer56.144Bobby Beyer
Mini CooperHP12:09.238Tom Tuttle2:11.042Tom Tuttle2:09.238Tom Tuttle99.0Tom Tuttle34.631Tom Tuttle37.306Tom Tuttle56.479Tom Tuttle

The best any driver of each car managed across the selected events, with who set it. Spellings and model years of the same car are grouped; click a row marked ▸ to see each version. Grouping is worked out from the names, so tell us if two cars are wrongly merged or split.

Rule changes between these events

Cal Club 2023 → Cal Club 2024 2023-02-24 to 2024-02-23

T1 Sequential Gearbox Limitations in T1

#33691 from David Mead · Rule change · TB 23-03 (2023-03 Fastrack)

neutralT1 cars with aftermarket sequential transmissions get 10-inch max bellhousing; non-sequential cars gain 100 lbs weight break.

In GCR, Section 9.1.9.1.I.4., change as follows:
"Aftermarket sequential transmissions are permitted. Cars with aftermarket sequential shift transmissions shall utilize a 1:1 (or
greater/overdriven) ratio in top gear. Transmission location must be OEM. Maximum bellhousing length is 10 inches. Cars that
don’t use an aftermarket sequential transmission may decrease their competition weight by 100 lbs."

T4 BMW 320I intercooler

#33762 from Chi Ho · Rule change · TB 23-03 (2023-03 Fastrack)

fasterT3 BMW 320I now permitted to use aftermarket intercooler.

In T3 Spec Lines, BMW- 320I, add to Notes the following:
"Aftermarket intercooler permitted."

T1 T1 GT4 adjustments

#33786 from Touring Committee · Rule change · TB 23-03 (2023-03 Fastrack)

fasterT1 GT4 all nine cars lose 125 lbs minimum weight with driver, from 3200–3575 to 3075–3450.

In Touring 1 - GT4 Spec Lines, change Min. Weight with Driver (LBS) as follows:
Aston Martin Vantage AMR GT4: "3575 3450"
Audi R8 GT4: "3550 3425"
BMW M4 GT4: "3500 3375"
Ford Mustang GT4: "3550 3425"
Maclaren 570S GT4: "3450 3325"
Mercedes AMG GT4: "3450 3325"
Porsche 718 Cayman GT4 CS MR: "3200 3075"

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Porsche 718 GT4 RS Clubsport: "3450 3325"
Toyota Supra GR GT4: "3350 3225"

T1 Sunset of pre 2023 Touring 1 Rules.

#33916 from Touring Committee · Rule change · TB 23-03 (2023-03 Fastrack)

neutralT1 removes GCR Section 9.1.9.1.A. and T1 Spec Lines entirely, sunsetting pre-2023 Touring 1 rules.

In T1, GCR Section 9.1.9.1.A., remove in its entirety.
In T1 Spec Lines, remove in its entirety.

T4 Request to Classify 2004-2008 Acura TSX in T4

#33590 from William Phee · Rule change · TB 23-04 (2023-04 Fastrack)

neutralAcura TSX 2004-2008 newly classified in T4 at 3000 lbs minimum weight with 2354cc engine.

In T4 Spec lines, classify Acura TSX (2004-2008) as follows:

A specification table follows in the original; it is not shown here.

T1 Clarification for Camaro Gen5 2010-2015

#33739 from Clark Nunes · Rule change · TB 23-04 (2023-04 Fastrack)

slowerT1 Chevrolet Camaro Gen5 LS3-6160 adds 70mm flat plate restrictor, weight 3550 lbs.

In T1 Spec Lines, Chevrolet Camaro Gen 5 ('10-'15) Including SS, Z28, classify Spec Line Number 1135 as follows:

A specification table follows in the original; it is not shown here.

T4 T4 Mustang Brakes/Swaybar

#34036 from Scotty B White · Rule change · TB 23-04 (2023-04 Fastrack)

fasterT4 Mustang rear sway bar increases from 22mm to 28mm permitted.

In T4 Spec Lines, Ford Mustang (2005-2010), change Notes as follows:
"Any sway bar up to F: 35mm and R: 22mm 28mm permitted."

T1 T1 GT4 adjustments

#33786 from Touring Committee · Rule change · TB 23-05 (2023-05 Fastrack)

neutralT1 GT4 weights clarified for nine cars, ranging from 3200 lbs Porsche 718 Cayman to 3575 lbs Aston Martin.

RM 23-04 – Touring 1 weights dated 3/21/2023
As an E&O to the February Fastrack, in T1-GT4 leave weights as follows:
Aston Martin Vantage AMR GT4: 3575
Audi R8 GT4: 3550
BMW M4 GT4: 3500
Ford Mustang GT4: 3550
Maclaren 570S GT4: 3450
Mercedes AMG GT4: 3450

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Porsche 718 Cayman GT4 CS MR: 3200
Porsche 718 GT4 RS Clubsport: 3450
Toyota Supra GR GT4: 3350

T1 Touring 1 Tire Sizes

#34191 from Club Racing Board · Rule change · TB 23-05 (2023-05 Fastrack)

fasterT1-GT4 McLaren 570S and Mercedes AMG GT4 front tires widen to 315 mm.

RM 23-05 – Touring 1 Tire Sizes dated 3/21/2023
In T1-GT4 change tire sizes as follows:
Maclaren 570S GT4 (f)285 315
(r)315
Mercedes AMG GT4 (f)275 315
(r)315

T1 Request to reinstate T1 S197 Mustang

#34048 from David Mead · Rule change · TB 23-06 (2023-05 Fastrack)

neutralT1 Ford Mustang S197 (05-14) reinstated with 3550 lbs minimum weight, 75mm restrictor, Voodoo engine permitted.

In T1 Spec Lines, classify Ford Mustang S197 (05-14) Includes GT, Boss302, 302S, 302R, FR500C, FR500S as follows:

A specification table follows in the original; it is not shown here.

Applies to Ford Mustang on this page: Pratt Cole

T4 05-06 Mini Wheel Weight

#34112 from Mav Singh · Rule change · TB 23-06 (2023-05 Fastrack)

fasterT4 Mini Cooper S all years now run 17-inch wheels, up from 16, with wider rims to 8 inches.

In T4 Spec Lines, Mini Cooper S (02-04), change as follows:
Wheel Size: "16 x 7 17 x 8"
Add to Notes: "Wheels conforming to B-spec rules are permitted."
In T4 Spec Lines, Mini Cooper S (05-06), change as follows:
Wheel Size: "16 x 7 17 x 8"
Add to Notes: "Wheels conforming to B-spec rules are permitted."
In T4 Spec Lines, Mini Cooper S (07-13), change as follows:
Wheel Size: "17 x 7 8"

T4 06-09 VW Rabbit

#34153 from Cameron Conover · Rule change · TB 23-06 (2023-05 Fastrack)

slowerT4 Volkswagen Rabbit 2.5 (06-09) consolidates 06-07 and 08-09 models; Integrated Engineering intake allowed with 25lb penalty.

In T4 Spec Lines, delete Volkswagen Rabbit 2.5 (06-07) in its entirety and change Volkswagen Rabbit 2.5 (08-09) as follows:
"Volkswagen Rabbit 2.5 (08 06-09)"
Add to Notes: "Integrated Engineering intake IEIMVB1-BK allowed with 25lb penalty."

T4 96-01 Audi a4 2.8 Spring Rate

#34217 from Michael Gordhamer · Rule change · TB 23-06 (2023-05 Fastrack)

fasterT4 Audi A4 2.8 V6 wheels grow to 17x8, tyres to 245, springs now 800lb with 32mm sway bars.

In T4 Spec Lines, Audi A4 V-6 (96-01) / Volkswagen Passat 2.8 V6 (96-05), change as follows:
Wheel Size: "16 x 7 17 x 8"
Tire Size: "225 245"
Notes: "The following items must remain stock: shock/struts (including mounts), original wheels, and transmission differential -
unless specified below. 800lb springs allowed. Front and rear sway bars permitted 32mm max."

HP Request to Classify Sonic and Fiesta in HP

#34264 from Greg Amy · Rule change · TB 23-06 (2023-05 Fastrack)

neutralFord Fiesta HP and Chevrolet Sonic FP model year ranges extended from 2016 to 2019.

In HP, adjust model years of the "Ford Fiesta (11-16)" spec line as follows:
"Ford Fiesta (11-16 9)"
In FP, adjust model years of the "Chevrolet Sonic (12-16)" spec line as follows:
"Chevrolet Sonic (12-16 9)"

T1 Gen 5 Camaro Engine

#33875 from Matt Spicuzzi · Rule change · TB 23-06 (2023-07 Fastrack)

neutralT1 Chevrolet Camaro Gen 5 LS7 gets two spec lines: 1131 with 70mm restrictor, 1136 with 53mm restrictor, both 3450 lbs minimum.

In T1-NEW Spec Lines, Chevrolet Camaro Gen 5 (10-15) Including SS, Z28, classify Spec Line Number 1131 and 1136 as follows:

A specification table follows in the original; it is not shown here.

T1 Inquiry to letter #33682

#34071 from Andrew Aquilante · Rule change · TB 23-06 (2023-07 Fastrack)

slowerT1 Chevrolet Camaro Gen 5, Corvette C5 and C6: engine resleeve restricted to stock parameters only, no longer LS3 bore/stroke.

In T1 NEW Spec Lines, Chevrolet Camaro Gen 5 (10-15) Including SS, Z28, change Engine Notes as follows:
1130: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."
1135: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement.May resleeve to stock parameters for engine repair
or replacement."
In T1 NEW Spec Lines, Chevrolet Corvette C5 (‘97-’04) – Includes: Z06, Coupe, Convertible, change Engine Notes as follows:
1132: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."

Show 18 more lines

1134: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."
1136: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."
1138: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."
In T1 NEW Spec Lines, Chevrolet Corvette C6 (05-13) - Includes Z51, GrandSport, Z06, Z06 Carbon, change Engine Notes as
follows:
1150: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."
1160: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."
1170: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."
1180: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."
1190: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair
or replacement."

T1 Viper Cleanup

#34107 from Scotty B White · Rule change · TB 23-06 (2023-05 Fastrack)

fasterT1 Dodge Viper ACR/ACR-X restrictor increases from 50mm to 60mm flat plate.

In T1 NEW Spec Lines, Dodge Viper ACR/ACR-X Spec Line 1360, change Required Restrictor as follows:
"50mm 60mm flat plate"

T1 Viper 8300 OEM FPR Size

#34268 from Scotty B White · Rule change · TB 23-06 (2023-05 Fastrack)

unclearT1 Dodge Viper ACR/ACR-X: Spec Line 1370 restrictor increases to 55mm, Line 1390 decreases to 55mm.

In T1 NEW Spec Lines, Dodge Viper ACR/ACR-X Spec Line 1370, change Required Restrictor as follows:
"(2) 47mm 55mm flat plates"
In T1 NEW Spec Lines, Dodge Viper ACR/ACR-X Spec Line 1390, change Required Restrictor as follows:
"(2) 60mm 55mm flat plates"

HP ITC to FP?

#34286 from David Snow · Rule change · TB 23-06 (2023-07 Fastrack)

neutralHP Volkswagen Rabbit Cabriolet 1780 removed; Rabbit 1588 and 1715 reclassified with engine sizes and year ranges specified.

In HP Spec Lines, Volkswagen Rabbit Cabriolet 1780, delete in its entirely:
In HP, Spec Lines, Volkswagen Rabbit, change Title as follows:
“Volkswagen Rabbit 1588 (includes Cabriolet / convertible)”
“Volkswagen Rabbit 1715 (81-84) (excl. conv.)”
“Volkswagen Rabbit GTI 1780 (83-84)”

T4 2002-2006 Mini Cooper S R53 Spec Line Request

#34336 from Aaron Fitzsimmons · Rule change · TB 23-06 (2023-07 Fastrack)

fasterT4 Mini Cooper S R53 loses 50 lbs, to 2700 for both 02-04 and 05-06 model years.

In T4 Spec Lines, Mini Cooper S (02-04), change Weight as follows:
"2750 2700"
In T4 Spec Lines, Mini Cooper S (05-06), change Weight as follows:
"2750 2700"

HP Correct Intake Valve Size on 1500cc Midget/Spitfire

#34419 from Production Committee · Rule change · TB 23-06 (2023-05 Fastrack)

neutralFP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44).

In FP Spec Lines, Austin-Healey Sprite Mk. I, II,III, IV MG Midget Mk I,II, III, IV & 1500, change Intake Valve Size as follows:
"(I) 36.65.3/(1.44)"
In FP Spec Lines, Triumph Spitfire Mk. IV & 1500, change Intake Valve Size as follows:
"(I) 36.65.5/(1.440)"
In HP Spec Lines, Triumph Spitfire 1500, change Intake Valve Size as follows:
"(I) 36.65.5/(1.440)"
In HP Spec Lines, Triumph Spitfire Mk. III & IV 1500, change Intake Valve Size as follows:
"(I) 36.65.5/(1.440)"

T1 Ford Mustang S197 (05-14) Clarification

#34450 from Club Racing Board · Rule change · TB 23-06 (2023-05 Fastrack)

neutralT1 Ford Mustang S197 05-14 now requires OEM 8.8 differential housing.

In T1-NEW Spec lines, Ford Mustang S197 (05-14) Includes GT, Boss302, 302S, 302R, FR500C, FR500S, change Notes as follows:
"OEM 8.8 Differential Housing"

T1 C5 Approved Aero That Was Mistakenly Deleted

#34374 from Joe Aquilante · Rule change · TB 23-08 (2023-08 Fastrack)

fasterT1 Corvette C5 gains approved aero parts: carbon rear spoiler, vented front splitter, side skirts, with 50 lb weight reduction allowed.

In T1 NEW Spec Lines, Chevrolet Corvette C5 (‘97-’04) – Includes: Z06, Coupe, Convertible, Spec Lines 1132-1138, add to Notes
as follows:
"Any option of OEM Bodywork parts may be used as basis for aero measurements. Rear spoiler max 5” Above bumper allowed.
+50lbs. The following parts are permitted, with a 50lb decrease from base weight, in lieu of the aero options permitted in
9.1.9.1.B: (C7Carbon Rear- Spoiler CCC5 EX- RSB-GB, Vented Front Splitter CCC5-FS-GB, Side Skirts CCC5 SS-GB.)"

T4 Rules Clarification for Mazda RX8 Spec Line

#34395 from Colin Koehler · Rule change · TB 23-08 (2023-08 Fastrack)

neutralT3 Mazda RX-8 removes transmission/final drive pairing requirement; T4 removes same requirement, adds Mazdaspeed radiator and coil spring kit.

In T3 Spec Lines, Mazda RX-8 Base/R3/Sport/ GT (04-12), change notes as follows:
"Use of 2009 R3 transmission is permitted with alternate gear ratios as listed. R3 transmission must be paired with the listed
alternate final drive. Front sway bar permitted 32mm MAX rear sway bar 19 MAX, Front springs max 750, 500 rear. Cold air
intake permitted. Header permitted. Aftermarket flywheel and single disc clutch permitted with no weight penalty."
In T4 Spec Lines, Mazda RX-8 Base/R3/Sport/ GT (04-12), change notes as follows:
"Mazdaspeed radiator #0000-01-8501 allowed. Use of 2009 R3 transmission is permitted with alternate gear ratios as listed. R3
transmission must be paired with the listed alternate final drive. Mazdaspeed coil spring kit #QSEA-34-01Z allowed. 60mm flat
plate restrictor required. OE Rear spoiler allowed #F151-V4-920F. OE front air dam allowed #F151-V4-900f-BB. Springs Allowed:

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(F) Mazda Motorsports- 0000- 04-9700-08 or Eibach- 0800.250.0700 (R) Mazda Motorsports- 0000-04-9400-07 or Eibach
0700.250.0400, and helper 0000-04-9926 allowed. Alternate sway bars allowed max 32mm (f) 19mm (r)."

T1 Why no Camaro?

#34421 from Scotty B White · Rule change · TB 23-08 (2023-05 Fastrack)

neutralChevrolet Camaro GT4-R classified in T1 GT4 Spec Line 4035, minimum weight 3375 lbs, 315 max tire, 63mm restrictor, ineligible for Runoffs.

In T1 GT4 Spec Lines, classify Chevrolet Camaro GT4-R as follows:

A specification table follows in the original; it is not shown here.

T4 rule book corrections

#34437 from Chi Ho · Rule change · TB 23-08 (2023-08 Fastrack)

fasterT3 BMW 320i (14-15) gains aftermarket intercooler permission; T4 loses it.

In T3 Spec Lines, BMW 320i (14-15), add to Notes the following:
"Aftermarket intercooler permitted."
In T4 Spec Lines, BMW 320i (14-15), remove from Notes the following:
"Aftermarket intercooler permitted."

T1 Request to Remove Expiration from T1 spec lines #1350 & #1370

#34470 from Scotty B White · Rule change · TB 23-08 (2023-05 Fastrack)

neutralT1 Dodge Viper ACR / SRT RT-10 and ACR/ACR-X spec lines 1350 and 1370 remove 12/23 expiration.

In T1 NEW Spec Lines, Dodge Viper ACR / SRT RT-10, change Spec Line Number as follows:
"1350 *Spec line Expires 12/23*"
In T1 NEW Spec Lines, Dodge Viper ACR/ACR-X, change Spec Line Number as follows:
"1370 *Spec line Expires 12/23*"

T1 Remove

#34475 from Touring Committee · Rule change · TB 23-08 (2023-05 Fastrack)

neutralT1 GT4 McLaren 570S, Mercedes AMG GT4, and Porsche 718 Cayman GT4 CS MR now eligible for Runoffs competition.

In T1 GT4 Spec Lines, Maclaren 570S GT4, Spec Line Number 4050, remove Notes as follows:
"**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**"
In T1 GT4 Spec Lines, Mercedes AMG GT4, Spec Line Number 4060, remove Notes as follows:
"**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**"
T1 GT4 Spec Lines, Porsche 718 Cayman GT4 CS MR, Spec Line Number 4070, remove Notes as follows:
"**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**"

T1 Error in T1 GT4 numbering scheme-

#34578 from Touring Committee · Rule change · TB 23-08 (2023-05 Fastrack)

neutralT1 GT4 BMW M4 Spec Line Number changed from 4050 to 4030.

In T1 GT4 Spec Lines, BMW M4, change Spec Line Number as follows:
"4050 4030"

T4 Ride Height Correction for the T3 Solstice.

#34615 from Joe Aquilante · Rule change · TB 23-08 (2023-08 Fastrack)

neutralT3 Pontiac Solstice GXP minimum ride height set to 3 inches.

In T2 Spec Lines, Pontiac Solstice GXP Coupe / Convertible (07-09), add to Notes the following:
"Minimum ride height is 3 inches."
In T3 Spec Lines, Pontiac Solstice GXP Coupe / Convertible (07-09), add to Notes the following:
"Minimum ride height is 3 inches."

T4 Inclusion of similar car. (CLK 320)

#34626 from Patrick Morgan · Rule change · TB 23-09 (2023-09 Fastrack)

neutralT4 Mercedes Benz CLK 320 Coupe model years expand to 2000-2007, C320 Sedan added.

In T4 Spec Lines, Mercedes Benz CLK 320 Coupe (2004), change as follows:
"Mercedes Benz CLK 320 Coupe, C320 Sedan (2004 2000-2007)

HP Larger chokes

#34681 from Brian Downey · Rule change · TB 23-09 (2023-09 Fastrack)

fasterHP Nissan/Datsun PL510 carburetors allow larger 4mm chokes, replacing 2mm specification.

In HP Spec Line, Nissan/Datsun PL510, change Carburetor. No. & Type as follows:
"(1) 40 DCN, DCNF w/ 32 4mm choke(s), . or (1) 36mm DCNVH. (2) auto type side draft(s) w/ 32 4mm choke(s) on I.R. manifold @
90lbs penalty."

T1 New T1 add spec line for C5 corvette LS2 engines (Copy from C6)

#33764 from Craig Anderson · Rule change · TB 23-12 (2023-09 Fastrack)

neutralT1 Chevrolet Corvette C5 LS2 added with 6000cc displacement, 3300 lbs minimum weight, 72mm flat plate restrictor.

In T1 Spec Lines, classify Chevrolet Corvette C5 (‘97-’04) – Includes: Z06, Coupe, Convertible as follows:

A specification table follows in the original; it is not shown here.

T1 2004 - 2006 Pontiac GTO Re-Integration Back Into T1

#34403 from Ed Gless · Rule change · TB 23-12 (2023-12 Fastrack)

neutralPontiac GTO 2006-2009 re-integrated into T1 with LS2 at 3400 lbs, 72mm restrictor, and LS3 at 3500 lbs, 61mm restrictor.

In T1 Spec Lines, classify Pontiac GTO 2006-2009 as follows:

A specification table follows in the original; it is not shown here.

Applies to Pontiac GTO on this page: Ed Gless

T1 Request to Classify Porsche 997-1 GT3 Cup

#34561 from Scotty B White · Rule change · TB 23-12 (2023-12 Fastrack)

neutralT1 Porsche 997-1 GT3 Cup added at spec line 4210, minimum weight 3050 lbs.

In T1 Spec Lines, delete the Porsche 996 GT3 Cup car from the standard spec lines and classify "Homologated car" section as
follows:
T1 – Homologated Cars

A specification table follows in the original; it is not shown here.

T1 C7 Corvette Rule Change Request

#34897 from Heath Karl · Rule change · TB 23-12 (2023-09 Fastrack)

neutralT1 Chevrolet Corvette C7 (14-19) including Z51, Grandsport newly classified as homologated car.

In T1 Spec Lines, classify Chevrolet Corvette C7 (14 - 19) - Includes Z51, Grandsport as follows:
T1 – Homologated Cars

A specification table follows in the original; it is not shown here.

HP Porsche 944/924S Rule Change Request

#35002 from Adam Achepohl · Rule change · TB 23-12 (2023-12 Fastrack)

neutralEP Porsche 944/924S combines 2.5L and 2.7L variants with new weights: 2250–2415 lbs depending on engine and year.

In EP Spec Lines, delete the Porsche 944/924S 2.5L (2V) (83-88) spec line entirely, and create a new spec line for Porsche
944/924S 2.5L(2V) 2.7L(2V) (83-89) as follows:

A specification table follows in the original; it is not shown here.

HP FP and HP Toyota Corolla

#35030 from Keith Church · Rule change · TB 23-12 (2023-12 Fastrack)

fasterFP Toyota Corolla 2TC loses 43 lbs to 1810; HP Corolla loses 50–52 lbs to 1910–2006.

In FP Spec Lines, Toyota Corolla 2TC (71-74), change weight as follows:
"1853 1810"
In HP Spec Lines, Toyota Corolla (71-74), change weight as follows:
“1960 1910
* 2009 1958
** 2058 2006”

HP Weight Reduction for Mazda 626

#35031 from David Reiter · Rule change · TB 23-12 (2023-12 Fastrack)

fasterHP Mazda 626 84-87 weight reduced to 2200 lbs, 2255 lbs, and 2310 lbs across three configurations.

In HP Spec Lines, Mazda 626 (84-87), change weight as follows:
"2300 2200
*2358 2255
**2415 2310"

HP Triumph GT6 Adjustments

#35054 from ANTHONY PARKER · Rule change · TB 23-12 (2023-12 Fastrack)

fasterEP Triumph GT6 minimum weight reduced to 1800 lbs.

In EP Spec Lines, Triumph GT6, change weight as follows:
"1830 1800"

T1 Camaro Gen 5 Weight Reduction Due to Competitive Disadvantage

#35092 from Clark Nunes · Rule change · TB 23-12 (2023-09 Fastrack)

fasterT1 Gen 5 Camaro minimum weight drops 75 lbs to 3475; restrictor increases 70mm to 75mm.

In T1 Spec Lines, Gen 5 Camaro, change as follows:
Spec Line 1130 - Minimum Weight "3550 3475"
Spec Line 1135 - Minimum Weight "3550 3475"
Restrictor Required "70mm 75mm-Flat Plate"

T1 Addendum to Letter #35022: Drivetrain Rule

#35105 from Clyde Greene · Rule change · TB 23-12 (2023-09 Fastrack)

neutralT1 Aston Martin Vantage permitted to use OEM Sportshift II transmission.

In T1 Spec Lines, Aston Martin Vantage, add to Chassis Notes as follows:
"OEM Sportshift II transmission permitted."

HP Request to Adjust Weight of 1988-1991 CRX/Civic

#35115 from Enrik Benazic · Rule change · TB 23-12 (2023-09 Fastrack)

fasterHP Honda CRX 1.5 (88-91) weight reduced to 2175 lbs, 2229 lbs, and 2284 lbs across three spec lines.

In HP Spec Lines, Honda CRX 1.5 (88-91), change weight as follows:
"2245 2175
*2301 2229
**2357 2284"

T4 Mazda MX-5 ND1 Spec Line Request

#34232 from Josh Smith · Rule change · TB 24-01 (2024-01 Fastrack)

slowerT4 Mazda MX-5 ND1 minimum weight increases 50 lbs to 2700; suspension springs now allow up to 500 lb front, 300 lb rear.

In T4 Spec Lines, Mazda MX-5 Miata/Club/ RF (16-18), change as follows:
Weight: "2650 2700"
Notes: "Factory bolt-in roll bar/ cross member may be removed to facilitate roll cage installation. The following item(s) must
remain stock: transmission differential unless specified below. Retractable hardtop option permitted but must be disabled from
moving action and positively fastened. Any OEM or aftermarket hardtop is permitted that retains the OEM roof silhouette,
including Mazda hardtop part #0000-07-5902-ND and part #0000-07-5901 (discontinued DG Motorsports). 29mm (f) 16mm (r)
sway bars allowed. Suspension package permitted with a 100 lbs. weight increase that includes the following parts: front springs
#0000-04-9700-08, rear springs #0000-04-9400-07, helper springs #0000-04-HLPR-EB (optional). Up to 500lb front and 300lb rear

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springs allowed. Mazda Motorsports Header part #0000-06-5410 allowed. Mazda tower brace 0000-04-5626 allowed."

T4 BRZ/FRS/86 Spring Allowance

#35038 from Luis Goncalves · Rule change · TB 24-01 (2024-01 Fastrack)

neutralT4 BRZ/FRS/86 spring allowance clarified: 225 lb front and 300 lb rear springs permitted; non-OEM LSD allowed with +50 lbs penalty.

In T4 Spec Lines, Scion FR-S/10 series (13-16), change Notes as follows:
"Eibach 82105.320, 4.10582 and SPC 67660 allowed. Eibach 82105.320 sway bar kit allowed. Eibach 4.10582 springs or 225 lb (f)
and 300 lb (r) springs allowed. SPC 67660 allowed. Front strut tower brace allowed. Raceseng, part # raceseng-ft86-r-shock-top
permitted. Non-OEM limited slip differential allowed with +50 lbs. weight penalty. 55mm flat plate restrictor required. Only 17”
wheels permitted."
In T4 Spec Lines, Subaru BRZ/ BRZ Limited (13-16), change Notes as follows:
"Eibach 82105.320, 4.10582 and SPC 67660 allowed. Eibach 82105.320 sway bar kit allowed. Eibach 4.10582 springs or 225 lb (f)
and 300 lb (r) springs allowed. SPC 67660 allowed. Front strut tower brace allowed. Raceseng, part # raceseng-ft86-r-shock-top

Show 12 more lines

permitted. Non-OEM limited slip differential allowed with +50 lbs. weight penalty. 55mm flat plate restrictor required. Only 17”
wheels permitted."
In T4 Spec Lines, Subaru BRZ (17-21), change Notes as follows:
"Eibach 82105.320, 4.10582 and SPC 67660 allowed. Eibach 82105.320 sway bar kit allowed. Eibach 4.10582 springs or 225 lb (f)
and 300 lb (r) springs allowed. SPC 67660 allowed. Front strut tower brace allowed. Raceseng, part # raceseng-ft86-r-shock-top
permitted. Non-OEM limited slip differential allowed with +50 lbs. weight penalty. 55mm flat plate restrictor required. Only 17”
wheels permitted."
In T4 Spec Lines, Toyota 86, GT (17-21), change Notes as follows:
"Eibach 82105.320, 4.10582 and SPC 67660 allowed. Eibach 82105.320 sway bar kit allowed. Eibach 4.10582 springs or 225 lb (f)
and 300 lb (r) springs allowed. SPC 67660 allowed. Front strut tower brace allowed. Raceseng, part # raceseng-ft86-r-shock-top
permitted. Non-OEM limited slip differential allowed with +50 lbs. weight penalty. 55mm flat plate restrictor required. Only 17”
wheels permitted."

HP Request to Review Z3 2.5 Spec Line

#35073 from Tim Schreyer · Rule change · TB 24-01 (2024-01 Fastrack)

slowerEP BMW Z3 2.5L weight increases to 2500 lbs, 2563 lbs with turbo, 2625 lbs with supercharger.

In EP spec line, BMW Z3 2.5L, change weight as follows:
"2450 2500
*2511 2563
**2573 2625"

HP Parity in HP

#35138 from Kendall Jones · Rule change · TB 24-01 (2024-01 Fastrack)

fasterHP Sprite/Midget Mk I–IV, Mk 1500 compression ratio raised to 12.0:1 at Prep Level 1/2.

In HP Spec Line, Austin-Healey Sprite Mk I, II, III, IV / MG Midget Mk I, II, III, IV & 1500, Prep Level 1/2, change Notes section as
follows:
"Compression ratio limited to 11 12.0:1"

T1 GT4 batch adjustment in T1

#35162 from Touring Committee · Rule change · TB 24-01 (2024-01 Fastrack)

unclearT1-GT4 batch adjustments: five cars lighter, two heavier, restrictors and ECU maps changed, five models now eligible for Runoffs.

In GCR, Section 9.1.9.1.A.T., change as follows:
"Tires- Tires must conform to GCR section 9.3.TIRES and als o must conform to spec line requirements. DOT approved tires are
permitted. Slicks conforming to the spec line are permitted."
In Touring 1 - Homologated Cars Spec Lines, 4100- BMW M2 ClubSport Racing, change Must Conform To as follows:
"Tires conforming to SRO TCX rules allowed. Must meet factory specs."
In Touring 1 - Homologated Cars Spec Lines, 4120- Ford Mustang FP350S 2017, change as follows:
Must Conform To: "Tires conforming to Trans Am SGT tire rules allowed Must meet factory specs."
Chassis Notes: "VIN not required. Additional permitted allowances: DOT tires required. Other consumables are open, alternate

Show 40 more lines

driveshaft permitted, aftermarket wheels and fuel cell per Touring category rules permitted. Shocks conforming to T1 rules
permitted. Alternative rear toe links permitted."
In T1-GT4 Spec Lines, change Chassis Notes as follows:
Aston Martin Vantage AMR GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)** Slick tires conforming to IMSA GT4
or SRO GT4 specs are permitted."
Audi R8 GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO GT4 specs
are permitted."
BMW M4 GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO GT4 specs
are permitted."
Chevrolet Camaro GT4-R: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO
GT4 specs are permitted."
Ford Mustang GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO GT4
specs are permitted."
Maclaren 570S GT4: "Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted."
Mercedes AMG GT4: "Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted."
Porsche 718 Cayman GT4 CS MR: "Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted."
Porsche 718 GT4 RS Club-sport: "Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted."
Toyota Supra GR GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO GT4
specs are permitted."
In T1-GT4 Spec Lines, change as follows:
Aston Martin Vantage AMR GT4:
Weight: “3575 3490”
Performance Control: “SRO power level ECU Map 3 IMSA Map id 11”
Chevrolet Camaro GT4-R:
Weight: “3375 3435”
Performance Control: “63 62mm”
Ford Mustang GT4:
Weight: “3550 3535”
Performance Control: “63 71mm SRO compliant restrictor IMSA ECU Cal”
Maclaren 570S GT4:
Weight: “3450 3250”
Performance Control: “SRO 2019 BOP ECU map SRO Rest 1”
Mercedes AMG GT4:
Weight: “3450 3470”
Performance Control: “Power level 2 map 5”
Porsche 718 Cayman GT4 CS MR:
Weight: “3200 3250”
Performance Control: “54 53.7mm”
Toyota Supra GR GT4:
Weight: “3350 3315”

T1 Remove T1 spec lines

#35192 from Touring Committee · Rule change · TB 24-01 (2024-01 Fastrack)

neutralT1 spec lines 1000, 1010, 1020, 1040, 1360, 1400–1410, 1520–1680, 1700–1720 deleted entirely.

In T1 Spec Lines, delete the following spec line numbers in their entirety:

A specification table follows in the original; it is not shown here.

T4 TSX Allowance

#35219 from Oscar Jackson · Rule change · TB 24-01 (2024-01 Fastrack)

fasterT4 Acura TSX 2004-2008 now allows header.

In T4 Spec Lines, Acura TSX (2004-2008), add to Notes the following:
"Header allowed."

HP Spitfire classification

#35224 from Michael Walz · Rule change · TB 24-01 (2024-01 Fastrack)

unclearHP Triumph Spitfire 1500 valve spec changes from 36.6/5.5/(1.44/0) to 36.6/(1.44).

In HP spec line, Triumph Spitfire 1500, make the following change to the Valves column:
"(I) 36.65.5/(1.440)"

T4 Requested Update of Model Years of 370Z

#35231 from Richard Kulach · Rule change · TB 24-01 (2024-01 Fastrack)

neutralT3 Nissan 370Z model years expanded to include NISMO Edition through 2022.

In T3 Spec Lines, Nissan 370Z (09-16) / 370Z NISMO Edition (09-13), change model as follows:
"Nissan 370Z (09-16) / 370Z NISMO Edition (09-13) ,incl. Nismo (2009-2022)"

HP Miata Alternate Head

#35253 from Don Tucker · Rule change · TB 24-01 (2024-01 Fastrack)

fasterEP Mazda MX-5 1.8L 1990-97 minimum weight drops to 2150 lbs; 1994-97 variants to 2000, 2050, 2100 lbs respectively.

In EP Spec Lines, Mazda MX-5 /Miata 1.8L (90-97), change weight as follows:
"2200 2150"
Mazda MX-5 /Miata (94-97)
"2035 2000
*2086 2050
**2137 2100"

HP Triumph GT6 Adjustments

#35255 from Anthony Parker · Rule change · TB 24-01 (2024-01 Fastrack)

fasterEP Triumph GT6 dual 1.75" carbs weight drops to 1940 lbs; triple Weber 40 DCOE options consolidated.

In EP spec line, Triumph GT6, make the following change in the Notes section:
"Two (2) 1.75” auto-type carburetors @ 1970 40 lbs. Three (3) Weber 40 DCOE on IR manifold with 28mm chokes @ 1990
lbs. Laycock overdrive, May use 5 speed gearbox w/o overdrive. Three (3) Weber 40mm DCOE w/28mm venturi on individual
runner manifold @ 2020 lb."

HP Honda S2000 throttle body

#35272 from Aaron Johnson · Rule change · TB 24-01 (2024-01 Fastrack)

fasterEP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm.

In EP spec line, Honda S2000, make the following changes to its spec line:
Fuel Injected Equipped Throttle Body Inside Diameter: "62 64"
Notes: "Comp. Ratio limited to 12.0:1. Valve lift limited to .500”. An adaptor plate can be used to mount the 62mm throttle body
from '00-05 to the '06-09 intake manifold. The adaptor plate can be no more than 1.25" thick, and its bore must not exceed the
"Fuel Injected Equipped Throttle Body Inside Diameter" maximum spec of 64mm."

HP Front Header/Nose Panel Alternate Material For 84-87 CRX

#35301 from Darryl Saylor · Rule change · TB 24-01 (2024-01 Fastrack)

neutralHP Honda CRX/Si 84-87 front header/nose panel may use alternate material if appearance remains stock.

In HP Spec Lines, Honda CRX/Si (84-87), in Notes, make the following change:
"Compression ratio limited to 11.0:1, Valve lift limited to .390”. The front header/nose body panel can be replaced by a
replica which may be constructed of an alternate material provided its appearance remains stock."

HP Correction within Triumph TR8 Spec Line

#35315 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)

neutralEP Triumph TR8 dry sump allowance moved from carburetor line to notes section.

In EP spec line, Triumph TR8 (78-81), move the "Dry sump allowed" wording to the appropriate location as follows:
Carburetor. No. & Type: “Zenith Stromberg carbs or fuel injection. Dry sump is allowed.”
Notes: “Comp. Ratio limited to 12.0:1, Valve lift limited to .500”. Dry sump is allowed.”

HP Correction to EP 924S/944 Spec Line

#35317 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)

neutralEP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs.

In EP spec line, Porsche 944/924S 2.5L (2V) / 2.7L (2V) (83-89), change Weight as follows:

A specification table follows in the original; it is not shown here.

HP Review Classification of HP Mazda 2

#35318 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)

slowerHP Mazda 2 (11-14) minimum weight increases to 1995 lbs, 2045 lbs with*, 2095 lbs with**.

In HP spec line, Mazda 2 (11-14), make the following weight changes:
"1920 1995
*1968 2045
**2016 2095"

T1 C8 Corvette T1 Restrictor Plate Request

#35213 from Garry Crook · Rule change · TB 24-02 (2024-02 Fastrack)

fasterC8 Corvette T1 restrictor plate increases from 70mm to 72mm flat plate.

In T1 NEW Spec Lines, Chevrolet Corvette C8 (20- 23) - Includes Z51, #1210, change Required Restrictor as follows:
"70mm 72mm - Flat Plate"

T4 More Car Lightening Stuff

#35319 from Scotty B White · Rule change · TB 24-02 (2024-02 Fastrack)

fasterT2, T3, T4 battery replacement wording simplified; OEM weight tolerance requirement removed.

In GCR, Section 9.1.9.2.D.1.g.3., change as follows:
"Batteries may be replaced provided the replacement is capable of starting the car. Batteries may not be relocated
unless noted on the spec line. Batteries must be adequately secured. Battery labeling must conform to 9.3.35.D. with
those of an alternate manufacturer, provided they are of similar amp-hour capacity, size and within 10% of OEM
weight."

T4 ND Missed Items

#35352 from Touring Committee · Rule change · TB 24-02 (2024-02 Fastrack)

neutralT4 Mazda MX-5 Miata/Club (16-18) and (19-21) permitted to replace 3rd and 4th gears with specific parts.

In T4 Spec Lines, Mazda MX-5 Miata/Club (16-18), add to Notes the following:
"3rd and 4th gear may be replaced with the following parts- (0000-02-5803-02, 0000-02-5803-01, 0000-02-5804-
02, 0000-02-5804-01)."
In T4 Spec Lines, Mazda MX5 Miata/Club/ RF (19-21), add to Notes the following:
"3rd and 4th gear may be replaced with the following parts- (0000-02-5803-02, 0000-02-5803-01, 0000-02-5804-
02, 0000-02-5804-01)."

Applies to Mazda MX-5 on this page: Oscar Jackson

Applies to Mazda Miata on this page: Kristina Etherington, Kayla Etherington

T4 Inclusion of B-C spec cars in T4

#35374 from Touring Committee · Rule change · TB 24-02 (2024-02 Fastrack)

neutralT4 now permits C-Spec cars to compete alongside B-Spec cars.

In GCR, Section 9.1.9.2., change as follows:
"Touring car eligibility: Cars are eligible for the class they are listed with a specification line and with the specific
allowances permitted. In addition, T2-T4 cars may race one class up in touring classes above their specification line class
as long as they are a legal T2-T4 car and conform to their specification line allowances as classified. Cars conforming to
C-Spec rules are permitted to compete in Touring 4."

T4 T2-T4 Set expiration dates on spec lines

#35378 from Touring Committee · Rule change · TB 24-02 (2024-02 Fastrack)

neutralT2-T4 spec lines for 46 cars expire 12/31/24; appeal required to continue.

In T2-T4 Spec Lines, add **This Spec line will expire 12/31/24, Please submit to appeal**
to Notes to the following Spec Lines:
T2:
Acura TL SHAWD (10-13)
Audi S4 (12-14)
Audi S5 (13-14)
Audi TT RS (2018-)
Cadillac ATS-V (16-17)

Show 46 more lines

Cadillac CTS-V (06-07)
Chevrolet Camaro SS (98-02)
Honda Civic (2017-)
Saturn Sky / Convertible (07-09)
Subaru Impreza WRX STi (03-07)
Subaru Impreza WRX STi (08-11)
T3:
Audi S4 (10-11)
Audi S4 (12-14)
Audi TTS Coupe (10-11)
Cadillac ATS (2015)
Chevrolet Cobalt (05-07)
Dodge SRT-4 (03-05)
Ford Fiesta ST (2014-)
Hyundai Genesis Coupe (2010-)
Hyundai Veloster Turbo (18-21)
Mazda RX-8 Base/R3/Sport/ GT (04-12)
Mini Cooper S (2016-)
Subaru WRX (02-05)
Toyota Camry (11-15)
T4:
Acura Integra GS-R VTEC (3 or 4 door) (94-01)
Audi A4 V-6 (96-01) / Volkswagen Passat 2.8 V6 (96-05)
BMW 320i (14-15)
Chevrolet Cobalt SS, Sport Coupe (06-10)
Chevrolet Sonic RS (2011-)
Chrysler/Dodge Neon ACR SOHC (4 door) (01-02)
Dodge Dart (14-15)
Dodge/Plymouth Neon ACR SOHC/DOHC (2/4 door) (95-99)
Fiat 500 Abarth (12-14)
Ford Focus SVT (02-04)
Ford Focus ZX4 ST (05-06)
Ford Focus (08-11)
Ford Mustang V-6 (01-04)
Honda Accord LX & EX (03-07)
Honda Accord LX-S/EX/EX-L (08-12)
Honda Civic Coupe Si (99-00)
Honda Civic SI (02-03)
Hyundai Elantra GLS (11-12)
Hyundai Tiburon V-6 (03-08)
Hyundai Veloster Turbo/ R-Spec (14-15)
Kia Forte Koup and Sedan LX/EX (10-13)
Kia Forte Koup and Sedan SX (10-13)
Kia Forte Koup (14-15)
Mazda Protégé ES (2000)
Mazda Protégé 5 (02-03)

T1 The Cars Have Expired

#35379 from Touring Committee · Rule change · TB 24-02 (2024-02 Fastrack)

neutralT1 NEW class removes 23 spec lines including Acura NSX, Ferrari, Porsche 996, Nissan Z cars, and others; Porsche 997 spec line 1680 expiration removed.

In GCR Contents, change as follows:
"9.1.9.1 TOURING (T1) CATEGORY NEW
T1 NEW"
In GCR, Section 9.1.9.1.Touring (T1) NEW Category Specifications, change as follows:
"9.1.9.1.Touring (T1) NEW Category Specifications"
In T1 NEW Spec Lines, change as follows:
"9.1.9.1.A T1 NEW Spec Lines"
"T1 NEW"

Show 26 more lines

In T1 NEW Spec Lines, delete the following Spec Lines in their entirety:
"Acura NSX (Spec Line 1000)
Acura NSX Turbo (Spec Line 1010)
Acura NSX Turbo World Challenge (Spec Line 1020)
Audi TTRS (GTS 2011 Spec) (Spec Line 1040)
Dodge Viper ACR/ACR-X (Spec Line 1360)
Ferrari 360 (Spec Line 1400)
Ferrari 430 (Spec Line 1410)
Ferrari 430 Challenge (Spec Line 1420)
Mazda MX-5 (06-15) (Spec Line 1520 and 1530)
Mazda RX-7 (Spec Line 1540)
Nissan GTR (Spec Line 1550)
Nissan 350/370Z (Spec Line 1560)
Nissan 370Z Supercharged (Spec Line 1570)
Nissan 350Z (Spec Line 1580)
Nissan 350Z/370Z (Spec Line 1590)
Porsche Cayman/S/GTS (05-15) (Spec Line 1600, 1610 and 1620)
Porsche Cayman GTS (2011) (Spec Line 1630)
Porsche 928 S4 Porsche 928 GTS-R (Spec Line 1640)
Porsche 996 (Spec Line 1650)
Porsche 996 TT OEM (Spec Line 1660)
Subaru WRX, WRX STI (05-2020) (Spec Line 1700)
Toyota Celica All-Trac (Spec Line 1710)
Toyota Supra MK4 (Spec Line 1720)"
In T1 NEW Spec Lines, Porsche 997, change Spec Line Number as follows:
"1680 *Spec line Expires 12/23*"

HP Update 1988-1991 Civic to Match 1988-1991 CRX

#35399 from Enrik Benazic · Rule change · TB 24-02 (2024-01 Fastrack)

fasterHP Honda Civic 1.5 (88-91) weight reduced to 2175 lbs base, 2229 lbs with power adder, 2284 lbs with two.

In HP, make the following weight change:
Honda Civic 1.5 (88-91)
“2245 2175
*2301 2229
**2357 2284”

Cal Club 2024 → Cal Club 2025 2024-02-23 to 2025-02-22

T4 Reorganize Spec Lines

#35375 from Touring Committee · Rule change · TB 24-03 (2024-03 Fastrack)

unclearT2-T4 Spec Lines remove wheelbase requirement, replace with Required Restrictor specification.

In T2-T4 Spec Lines, change Spec Line as follows:
"Wheel- base (mm) Required Restrictor"

T1 9.1.9.1 T1 new category item/ line 26 rule to expire Jan 1 2023

#35411 from Geoffrey Hegel · Rule change · TB 24-03 (2024-03 Fastrack)

neutralPontiac GTO 2006-2009 LS1 added to T1 as Spec Line 1590, 5700 cc, 3400 lbs minimum.

In T1 Spec Lines, classify Pontiac GTO 2006-2009 as Spec Line Number 1590 as follows:

A specification table follows in the original; it is not shown here.

T4 Allow any 400lb rear spring in the RX8

#35433 from Raymond Blethen · Rule change · TB 24-03 (2024-03 Fastrack)

neutralT4 Mazda RX-8 rear spring opens to any 400lb, was specific part numbers only.

In T4 Spec Lines, Mazda RX-8 Base/R3/Sport/ GT (04-12), change Notes as follows:
"Mazda Motorsports- 0000- 04-9700-08 or Eibach- 0800.250.0700 (R) Mazda Motorsports- 0000-04-9400-07 or Eibach
0700.250.0400, and helper 0000-04-9926 allowed. Springs allowed 700lb (f), 400(r)."

T4 370Z Brake Rotor Size Correction

#35487 from Derek Chan · Rule change · TB 24-03 (2024-03 Fastrack)

neutralT2 and T3 Nissan 370Z brake rotors enlarged: front 320x28 to 355x32mm, rear 320x16 to 350x20mm vented.

In T2 Spec Lines, Nissan 370Z (09-17) / 370Z NISMO Edition (09-17), change Brakes (mm) as follows:
"(F)320 x 28 Vented R)320 x 16 Vented : (F) 355x32mm Vented(R) 350x20mm Vented”
In T3 Spec Lines, Nissan 370Z, incl. Nismo (2009-2022), change Brakes (mm) as follows:
"(F)320 x 28 Vented (R)320 x 16 Vented : (F) 355x32mm Vented(R) 350x20mm Vented”

HP GCR Correction - Redundant HP Spec Lines

#35623 from Production Committee · Rule change · TB 24-03 (2024-03 Fastrack)

neutralHP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve, Scirocco 1588.

In HP Spec Lines, delete the following redundant spec lines in their entirety:
Spec line #10 - VW Rabbit Cabriolet 1780
Spec line #3 - VW Scirocco 1588
Spec line #4 - VW Scirocco 1780 (8-valve) (83-88)
Spec line #5 - VW Scirocco 1588

T1 Honda S2000

#35582 from Touring Committee · Rule change · TB 24-04 (2024-04 Fastrack)

neutralT1 Honda S2000 classified with 2400 lb minimum weight, 2950 cc displacement, 4.75" supercharger pulley.

In T1 Spec Lines, classify Honda S2000 as follows:

A specification table follows in the original; it is not shown here.

T4 Corrections to T4 RX8 Spec line

#35767 from Touring Committee · Rule change · TB 24-04 (2024-04 Fastrack)

neutralT4 Mazda RX-8 allows Mazdaspeed radiator, coil spring kit, OE rear spoiler, front air dam, springs to 700 lb front/400 lb rear, oil metering pump bypass, sway bars to 32 mm front/19 mm rear.

In T4 Spec Lines, Mazda RX-8 Base/R3/Sport/ GT (04-12), change Notes as follows:
"Mazdaspeed radiator #0000-01-8501 allowed. Mazdaspeed coil spring kit #QSEA-34-01Z allowed. OE Rear spoiler allowed
#F151-V4-920F. OE front air dam allowed #F151-V4-900f-BB. Springs allowed 700lb (f) max, 400(r) max. Oil metering pump may
be bypassed. Alternate sway bars allowed max 32mm (f) 19mm (r)."

T4 Allow T4 and T3 RX8 to Disable/Remove Factory Oil Inj.

#35761 from David Mead · Rule change · TB 24-05 (2024-05 Fastrack)

unclearT3 and T4 Mazda RX-8 may remove or disable factory oil injection system.

In T3 Spec Lines, Mazda RX-8 Base/R3/Sport/ GT (04-12), add to Notes as follows:
"OEM oil injection system may be removed or disabled."
In T4 Spec Lines, Mazda RX-8 Base/R3/Sport/ GT (04-12), add to Notes as follows:
"OEM oil injection system may be removed or disabled."

T4 2023 ND2 Miata Classification and Allowances

#35837 from Coyote Black · Rule change · TB 24-05 (2024-05 Fastrack)

slowerT4 Mazda MX5 Miata/Club/RF year range extended to 2024, suspension package permitted with 100 lbs weight increase.

In T4 Spec Lines, Mazda MX5 Miata/Club/ RF (19-21), change Year as follows:
"(19-21 24)"
In T4 Spec Lines, Mazda MX5 Miata/Club/ RF (19-21), add to Notes as follows:
"Suspension package permitted with a 100 lbs. weight increase that includes the following parts: front springs #0000-04-9700-
08, springs up to 500lb front and 300lb rear allowed. Mazda tower brace 0000-04-5626 allowed."

T4 Errors and Omissions for 06-09 VW Rabbit Rotor

#35851 from Andrew Burke · Rule change · TB 24-05 (2024-05 Fastrack)

fasterT4 Volkswagen Rabbit 2.5 (06-09) front brakes increase from 228 to 288 vented disc.

In T4 Spec Lines, Volkswagen Rabbit 2.5 (06-09), change Brakes as follows:
"(F) 228 288 Vented Disc (R) 260 Solid Disc"

HP Replace plastic panels

#35875 from Darryl Saylor · Rule change · TB 24-05 (2024-05 Fastrack)

neutralHP Honda CRX/Si 84-87 plastic panels can be replaced with replica alternate material if stock appearance maintained.

In HP spec line "Honda CRX/Si (84-87)", make the following change to the Notes section:
"The plastic OE front header/nose body panel, lower rocker side-skirt, and lower door cap panel can be replaced by a
replica, which may be constructed of an alternate material, provided its appearance remains stock."

T4 Driveshafts

#35916 from Scotty B White · Rule change · TB 24-05 (2024-05 Fastrack)

slowerT2, T3, T4 driveshafts may use alternative materials or one-piece units; non-OEM adds 25 lbs.

In GCR Section 9.1.9.2.D.4.b., add the following:
"6. T2-T3- Driveshafts may be replaced with alternative materials ie. carbon fiber, aluminum, steel. Two-piece driveshafts may
be replaced with one-piece units. If non-OEM driveshaft is used, add 25 lbs."

T1 Please Expedite classing the C63 Mercedes

#35987 from Touring Committee · Rule change · TB 24-05 (2024-05 Fastrack)

neutralMercedes AMG-C63 S (2023) classified in T1 with 4000 lbs minimum weight and 3700 restrictor.

In T1 Spec Lines, classify Mercedes AMG-C63 S (2023) as follows:

A specification table follows in the original; it is not shown here.

T4 GCR ERROR - letter not properly applied to GCR

#35999 from Touring Committee · Rule change · TB 24-05 (2024-05 Fastrack)

fasterT4 Mazda MX-5 Miata/Club 16-18 removes differential stock requirement, allows up to 500lb front and 300lb rear springs.

In T4 Spec Lines, Mazda MX-5 Miata/Club (16-18), change Notes as follows:
"Factory bolt-in roll bar/ cross member may be removed to facilitate roll cage installation. The following item(s) must remain
stock: transmission differential unless specified below. Retractable hardtop option permitted but must be disabled from moving
action and positively fastened. Any OEM or aftermarket hardtop is permitted that retains the OEM roof silhouette, including
Mazda hardtop part #0000-07-5902-ND and part #0000-07-5901 (discontinued DG Motorsports). 29mm (f) 16mm (r) sway bars
allowed. Suspension package permitted with a 100 lbs. weight increase that includes the following parts: front springs #0000-
04-9700-08, rear springs #0000-04-9400-07, helper springs #0000-04-HLPR-EB (optional). Up to 500lb front and 300lb rear
springs allowed. Mazda Motorsports Header part #0000-06-5410 allowed. Mazda tower brace 0000-04-5626 allowed."

Applies to Mazda MX-5 on this page: Oscar Jackson

Applies to Mazda Miata on this page: Kristina Etherington, Kayla Etherington

HP NIssan 300ZX Z31 to EP

#35830 from Murphy Nichols · Rule change · TB 24-06 (2024-06 Fastrack)

neutralNissan 300ZX 84-89 classified to EP at 2550 lbs minimum, 2960cc 6-cyl SOHC, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit.

In EP Spec Lines, classify Nissan 300ZX (84-89), as follows:

A specification table follows in the original; it is not shown here.

T4 Allow OEM Front Spoiler 06-08 Miata in T4

#35941 from David Mead · Rule change · TB 24-06 (2024-06 Fastrack)

fasterT4 Mazda MX-5 Club 06-15 now permits OEM front spoiler NF51-V4-900F.

In T4 Spec Lines, Mazda MX-5 / Club Model (06-15), add to Notes the following: "Front
spoiler permitted (NF51-V4-900F)."

Applies to Mazda MX-5 on this page: Oscar Jackson

HP RX7 1993 and Up Request In EP Spec Lines, classify

#36031 from Edward Zabinski · Rule change · TB 24-06 (2024-06 Fastrack)

neutralMazda RX-7 92-97 newly classified EP Prep Level 2 at 2200–2310 lbs with 13B 6-port rotary engine.

Mazda RX-7 (92-97) as follows:

A specification table follows in the original; it is not shown here.

T4 T4 Mustang Weight Reduction In T4 Spec

#36051 from Scotty B White · Rule change · TB 24-06 (2024-06 Fastrack)

fasterT4 Ford Mustang V6 (05-10) weight reduced 50 lbs to 3225.

Lines, Ford Mustang V6 (05-10), change as follows:
Weight: "3275 3225"
Notes: "14” Brembo Brake Kit#M-2300-S permitted."

T4 R53 Mini Cooper S spec line request In

#36056 from Manvinder Singh · Rule change · TB 24-06 (2024-06 Fastrack)

fasterT4 Mini Cooper S 02-04 and 05-06 now allow Milltek exhaust manifold #SSXM459 and 25mm rear sway bar.

T4 Spec Lines, Mini Cooper S (02-04), add to Notes the following:
"Milltek exhaust manifold #SSXM459 allowed. 25mm rear sway bar allowed."
T4 Spec Lines, Mini Cooper S (05-06), add to Notes the following:
"Milltek exhaust manifold #SSXM459 allowed. 25mm rear sway bar allowed."

HP Clean-up Multiple EP RX-8 Spec Lines In EP

#36156 from Production Committee · Rule change · TB 24-06 (2024-06 Fastrack)

neutralEP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains.

Spec Lines, make the following changes to the two Mazda RX-8 spec lines.
Remove spec line entirely:
Mazda RX-8 (04-11)
Remove the wording "alternate":
Mazda RX-8 (04-11)(alternate)
Spec Mazda (SM/SMX) None.

T4 Mustang T2/T3

#35877 from Scotty B White · Rule change · TB 24-07 (2024-07 Fastrack)

unclearFord Mustang GT 5.0L and V6 now permit Track/Performance Package parts in T2 and T3.

In T2 Spec Lines, Ford Mustang GT 5.0L (15-17), add to Notes as follows:
"Track/Performance Package parts permitted."
In T2 Spec Lines, Ford Mustang GT 5.0L (2018-), add to Notes as follows:
"Track/Performance Package parts permitted."
In T3 Spec Lines, Ford Mustang V6 (15-17), change Notes as follows:
"Track/Performance package allowed."

T4 Homologation of car to T4

#36030 from Patrick E Morgan · Rule change · TB 24-07 (2024-07 Fastrack)

neutralMercedes C300 4Matic 2008-2011 homologated to T4 at 3,725 lbs with 18x8.5 wheels, 245 max tires, 3.27 final drive.

In T4 Spec Lines, Mercedes C300 4Matic (2008-2011), classify as follows:

A specification table follows in the original; it is not shown here.

T4 T2-T4 Driveshaft Mistake...?

#36050 from Scotty B White · Rule change · TB 24-07 (2024-07 Fastrack)

fasterT2-T4 Ford Mustangs: remove 25 lbs penalty for non-OEM driveshaft, clarify alternate driveshaft allowances.

In GCR Section 9.1.9.2.D.4.b.6., remove as follows:
"If non-OEM driveshaft is used, add 25 lbs."
In T2 Spec Lines, Ford Mustang V6 (11-14), change Notes as follows:
"Driveshaft from Alternate metallic driveshaft is allowed."
In T2 Spec Lines, Ford Mustang Boss 302 (12-13), change Notes as follows:
"Alternate metallic driveshaft is allowed."
In T2 Spec Lines, Ford Mustang GT 5.0L (11-14)ki, change Notes as follows:
"Alternate metallic driveshaft is allowed."

Show 12 more lines

In T2 Spec Lines, Ford Mustang GT 5.0L (15-17), change Notes as follows:
"Alternate metallic driveshaft is allowed."
In T2 Spec Lines, Ford Mustang GT 5.0L (2018-), change Notes as follows:
"Alternate metallic driveshaft is allowed."
In T2 Spec Lines, Ford Mustang Coupe GT & Shelby GT 4.6L (05-10), change Notes as follows:
'An Aluminum driveshaft is allowed."
"Alternate metallic driveshaft is allowed."
In T3 Spec Lines, Ford Mustang Coupe GT & Shelby GT 4.6L & Cal. Special (05-10), change Notes as follows:
"An Aluminum driveshaft is allowed."
"Alternate metallic driveshaft is allowed."
In T3 Spec Lines, Ford Mustang V6 (11-14), change Notes as follows:
"Driveshaft from Alternate metallic driveshaft is allowed."

T4 MINI Cooper S Spec Lines Corrections.

#36086 from David Oliveira · Rule change · TB 24-07 (2024-07 Fastrack)

neutralT4 Mini Cooper S (02-04) deleted; (05-06) model year corrected to R53; (07-13) R56 simplified specs; (2014-2023) added with spring rates.

In T4 Spec Lines, Mini Cooper S (02-04), delete spec line in its entirety.
In T4 Spec Lines, Mini Cooper S (05-06), change Model as follows:
"Mini Cooper S R53 (0205-06)"
In T4 Spec Lines, Mini Cooper S (07-13), change Model and Notes as follows:
"Mini Cooper S R56 (07-13)"
Notes: "The following items must remain stock: shock/struts (including mounts), original wheels, and transmission
differential - unless specified below. Convertible model not allowed. Factory optional limited slip differential allowed.
JCW struts (F) 31 31 6 768 410 (R)33 52 6 768 412, springs (F)31 33 6 768 415 (R)33 53 6 768 418. May de-camber

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wheels by the use of slotted adjusters at the top of the strut mounting plates. They shall be located on the existing
chassis structure, utilizing the manufacturers original bolt holes and may not serve as reinforcement for that
structure. Any spring up to a maximum spring rate of 500 lbs. front and 800 lbs. rear may be used. Wheels conforming
to B-spec rules are permitted."
In T4 Spec Lines, Mini Cooper S (2016-), change Model and add to Notes as follows:
"Mini Cooper S (20142016-2023)"
Notes: "Convertible model not allowed. Any spring up to a maximum spring rate of 500lbs. front and 800lbs. rear may
be used."

T4 Allow Removal of Sound Tubes

#36130 from Coyote Black · Rule change · TB 24-07 (2024-07 Fastrack)

fasterT4 OEM intake chambers, resonators and acoustic devices may be removed if ports sealed and before restrictor.

In GCR Section 9.1.9.2.D.1.b., add the following:
"2. OEM intake- Chambers, resonators and acoustic devices may be removed, provided; that their ports are located
prior to any required restrictor, their ports are completely sealed, and that the part serves no other purpose."

T4 B8/8.5 Audi S4 T3 and T2

#36195 from Brian Leib · Rule change · TB 24-07 (2024-07 Fastrack)

neutralAudi S4 (2000-2002) moves to T3 with 3400 lbs minimum weight, 38mm turbo inlet restrictor required.

In T3 Spec Lines, Classify Audi S4 (2000-2002) as follows and allow the T2 spec line to expire.

A specification table follows in the original; it is not shown here.

HP Errant entry in HP production line item

#36231 from Angus Crome · Rule change · TB 24-08 (2024-08 Fastrack)

neutralHP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in).

In HP Spec Lines, change Track (F/R)mm/(in.) as follows:
Volkswagen Golf (GTI, GT, GL) (85-92): "2 1537/1529 (60.5/60.2)"
Volkswagen Jetta (GLI, GL) (85-92): "2 1537/1529 (60.5/60.2)"

T4 T4 Camaro V6 weight reduction

#36232 from Ted Warning · Rule change · TB 24-08 (2024-08 Fastrack)

fasterT4 Chevrolet Camaro V-6 (96-02) weight reduced from 3250 lbs to 3150 lbs.

In T4 Spec Lines, Chevrolet Camaro V-6 (96-02), change weight as follows:
"3250 3150"

T4 BOP adjustment for ND MX5s

#36345 from Touring Committee · Rule change · TB 24-08 (2024-08 Fastrack)

fasterT4 Mazda MX-5 Miata/Club 16-18 drops 50 lbs to 2650; 19-24 RF drops 50 lbs to 2750.

In T4 Spec Lines, change Weight (lbs) as follows:
Mazda MX-5 Miata/Club (16-18): "2700 2650"
Mazda MX5 Miata/Club/ RF (19-24): "2800 2750"

SM SMX Camera Rule Correction

#36496 from Paul Gauzens · Rule change · TB 24-09 (2024-09 Fastrack)

neutralSMX Spec MX-5 camera requirement wording changed; non-functioning recorder now grounds for penalty or disqualification.

In GCR, Section 9.1.7.1.D.21., change as follows:
"Cars running in Spec MX-5 must have a functioning video recorder/camera during all qualifying and race sessions as described
in 9.3.11. Upon request by an SCCA official, competitors must provide their video recording/data, which may be used by the
SCCA for any purpose including but not limited to rule enforcement and marketing. Failure to comply with a video request from
an official, or having a non-functioning video recorder/camera may will be grounds for penalty or disqualification."

SM Committee) AIM ECU Protocol

#36556 from Spec Mazda (SM/SMX · Rule change · TB 24-09 (2024-09 Fastrack)

neutralSMX Spec MX-5 must run latest AIM Data Logger Spec MX-5 ECU Protocol; wording clarification for technical compliance.

In GCR, Section 9.1.7.1.D.20., add the following:
“e. All cars must run the latest AIM Data Logger Spec MX-5 ECU Protocol.”
These specifications are part of the SCCA GCR and all automobiles shall conform to GCR Section 9.
A. PURPOSE AND
INTENT
Spec MX-5 (SMX) is based on four pillars: affordability, reliability, tech-ability, and fun to drive, the (SMX) Spec MX-5 car
provides the membership with the opportunity to compete in similarly prepared, low cost, 2006-2015 production-based MX-
5 car with limited modifications, intended to help deliver the most fair and competitive racing competition in SCCA Road

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Racing
B. CLASSIFIED CARS
AND WEIGHTS
2006-2015 production-based MX-5
Cars are to be weighed with the driver and required ballast.
C. AUTHORIZED
MODIFICATIONS
Only the left-hand drive, North American-version of the 2006-2015 Mazda MX-5 convertible & power retractable hardtop
(PRHT) are eligible. The original OE vehicle identification number (VIN) stamped on the firewall must correspond with the
model year automobile as classified. VIN plates or stampings must remain in place, with the firewall VIN taking precedence.
A Mazda Factory Shop Manual for the specific make, model, and year of automobile is required to be in the possession
of each entrant. The manual may be in the form of printed material, microfiche, CDs, DVDs, and/ or Internet access to
manufacturer sponsored web-based databases that is readily accessible at time of inspection. The manual is intended to
aid scrutineers in identifying parts and the configuration of the automobile.
The items outlined in this VTS document represent the only modifications and safety items permitted and/or required on
Spec MX-5 vehicles other than safety items as required in SCCA’s current GCR Section
9. Parts and components may not perform an unauthorized function (i.e. Modifications must be stated as authorized or
cannot be done).
If the Mazda Factory Manual or these rules provide only a partial specification or no specification at all, the Mazda parts may
not be modified beyond what is permitted in these rules. Compliance will be determined by comparison to new or like parts
and/or the parts compliance measurement listing delivered by Mazda. Other approved parts with only a partial specification
or no specification available in these rules may not be modified.
Assembly, rebuild, and refurbishment procedures, and all associated dimensions must adhere to the published factory
service procedures, except as otherwise stated in these rules. No components may be added or omitted from those
specified by the published factory service procedures. All components must be comply with stated standard dimensions.
It is permitted to use industry standard procedures to repair damaged components.
The use of any painting, coating, plating, metal treatment process or impregnating substance (e.g., anti- friction, thermal
barrier, oil shedding coatings, chrome, anodizing, REM, isotropic finishing, etc.) to any internal engine surface, internal
axle components, internal transmission or differential surface, internal or external surfaces of the intake manifold, exhaust
manifold or down tube, is prohibited.
D. VEHICLE
TECHNICAL
SPECIFICATIONS
(VTS)
1. Vehicle Weight
a. The minimum vehicle weight with driver is 2,525.0 lb.
2. Ballast
If ballast is required to meet the required minimum weight, it must be added as follows:
a. A ballast base plate must be securely mounted using the factory OE passenger seat mounting bolt holes and bolts. Any number
of additional segments of ballast may be attached to the base plate.
b. Each segment of ballast must be fastened to the base plate with a minimum of two (2) one-half (1/2) inch bolts/studs and
positive lock nuts of SAE Grade 5/ Metric 8.8 or better and must utilize large diameter, load distributing washers. In lieu of
positive lock nuts it is permitted to positively thread the additional segments of weight into the base plate.
c. Holes are not permitted to be drilled in the floor pan to mount ballast.
3. Chassis
a. Towing eyes per SCCA’s current GCR Section 9.3 are required. There must be an arrow that strongly contrasts with the vehicle
paint scheme pointing to each tow eyestrap.
9.1.7.1 SPEC MX-5 (SMX)
b. All cars must use the front subframe PT# - NE51-34-800C
c. All cars must use the rear subframe PT# - NE51-28-800B.
d. OE strut tower brace is required; it is comprised of three (3) components; see Table 1 for part numbers.
e. An engine to fender brace located on the passenger side of the engine bay may be used if mounted in such a way that it does not foul brake
lines, fuel lines, or other systems that would interfere with the safe operation of the vehicle under race conditions – see Table 1 for allowed
modifications. (Mazda Motorsports PT# 0000-07-5600)
f. Disabling or removing of the door locking mechanism must be performed.
g. To facilitate frequent lifting of the vehicle, a 3/4” boxed tube not to exceed 12” long may be added under the rocker panel inboard of
the factory pinch weld flange on each side of the vehicle.
h. Convertible tops/power retractable hard tops (PRHT) and attaching hardware must be completely removed.
i. All chassis, structural, and electrical repairs, if performed, must be in conformity with factory procedures, specifications, and dimensions.
Unless specifically authorized by the manufacturer for repair or permitted by these rules, no reinforcement (e.g., seam welding, material
addition, etc.) is permitted.
j. Removal of excess wiring is permitted provided it serves no other purpose and does not splice or interrupt the OE harnesses. Removal of the
following systems is permitted: audio equip- ment; power seats; airbag/supplemental restraint systems components; heated seats; interior
lighting; power windows; and power door locks. (No additional wiring may be added except as permitted in other sections - e.g., Section 16:
Electrical Equipment.)
Table 1: Strut Tower Brace Parts
Description Mazda Part #
Right Side of Strut Tower
Brace
NE57-56-48X
Left Side of Strut Tower
Brace
NE57-56-49X
Center Section of Strut
Tower Brace
NE57-56-48ZA
k. A hole is permitted to be drilled in part #’s NE57-56-48X and NE57-56-49X to allow for access to the shock adjuster screw is permitted (it is
recommended that the hole not be larger than 15mm); NE57-56-48X may be modified in order to allow room for the engine passenger side
engine brace; no other modifications or other braces are permitted.
l. MX-5 donor chassis with originally equipped with 16” OE wheels require installation of
OE strut tower brace (part # NE57-56-35XA).
m. To facilitate engine bay air flow for cooling purposes it is permitted to remove the section outlined below in red from OE PT# NE57-56-
35XA. Block-off plates must be installed at the fresh air vent for the HVAC module at the firewall under the cowl to isolate driver
compart- ment from engine compartment.
(FIREWALL BLOCKOFF PLATE 0000-07-5832) No additional modifications are permitted.
4. Body
a. Interior and exterior door handles are required to remain operable. Alternate interior door handles or cord/strap are permitted.
b. The driver’s and passenger’s side inner door structural panel may be removed to fit the cage.
c. The stock side impact/anti-intrusion beam must not be modified or removed.
d. Door locking mechanisms must be disabled or removed.
e. A minimum of two (2) of the brake lights must be in working order per the current GCR Section 9.1.
f. The two (2) OE unmodified, external mirrors for the correct the Mazda MX-5 (left and right) are required; they must be
mounted in stock location and may not be modified.
g. OE interior rearview mirror or an aftermarket rearview mirror must be used.
h. 2006-2015 MX-5 bodywork may be updated or backdated, OE body parts only. (This includes Mazda OE accessory body
parts such as trunk lid spoiler, side skirts, front air dam.)
i. Mazda Motorsports’ fiberglass headlamp replacements may be used; (See table 2)
no modifications or substitutions are permitted; exceptions: painting, covering, and wrapping.
Table 2: Headlamp Replacement Covers
Model Year Mazda Part # Description
2006-2008 0000-07-5818-LT Left Side
2006-2008 0000-07-5818-RT Right Side
2009-2015 0000-07-5819-LT Left Side
2009-2015 0000-07-5819-RT Right Side
j. Lexan windshield may be used in place of the stock windshield. (Mazda Motorsports PT# -
0000-07-5101-5S)
k. Windshield clips per current GCR Section 9.3 windshield clips are recommended.
l. Hood and trunk pins or clips are permitted. Factory hood and trunk latches must remain intact and operational and may not be
removed, disabled or altered.
m. Front under hood weather strip must remain intact PT#- NE51-56-750
n. Rear under hood weather strip must remain intact PT#- NE51-56-760
o. Modification of release cables is permitted to facilitate external pull/opening straps/pulls/cords.
p. A radiator screen of 0.125” minimum stainless-steel mesh may be added in front of the radiator.
1. The screen must be a single layer and must be installed to the bumper cover and or grill and be contained entirely within the
bodywork of the vehicle.
2. Tape may be applied to the mesh screen.
3. The OE grill must remain intact.
q. It is allowed to apply roll bar padding to the crash support bar (52-070) located behind the front bumper to prevent damage to the
bumper.
r. Front and rear fender lips may be rolled to prevent tire damage.
s. Front OE fender liners must be intact and unmodified, except for what is allowed in section 13. J regarding brake ducts.
Repairs due to on-track damage is allowed so long as it serves no other purpose.
t. OE fog lights lens/glass must be removed. This will allow for the installation of brake duct kit (Mazda Motorsports’ part # 0000-03-
5301-NC.) The remaining opening from the fog light lens must either be blocked, or a connection must be made from the fog lamp
opening/hole in the bumper fascia to a brake duct attached to the hub.
u. Side marker lenses may be removed, and holes may be covered.
v. OE hard top or the unmodified Mazda Motorsports hard top (part # 0000-07-5901-CC)
are permitted.
w. PRHT chassis cars must trim the finish panel with the 3rd brake light to fit one of the approved hard tops.
1. Hhardtops may be painted or wrapped.
2. OE hard top latches must be removed and replaced with positive fasteners.
3. The front of the hard top may attach to the upper windshield bar of the roll cage.
4. It is permitted to run one single piece of racer tape to cover the leading edge of the after- market hard top where it meets
the factory windshield frame.
5. Openings beneath the hard top seal to the body are not permitted. The hard top must be securely mounted to the body of the vehicle
and perform no other purpose.
6. Body repair must be performed to maintain stock body contours, lips, profiles, etc. body repair modification must not increase clearance.
x. To improve driver’s exit through the window area, the driver and passenger vent window and vent window supporting frame may be removed
as an assembly.
1. Vent windows may be modified to accept fresh air ducting.
y. OE radio antennas may be removed. Antennas for two-way radios may be added.
z. Insulation & undercoating may be removed.
aa. All cars must run with both the front door windows fully open (i.e. fully down).
5. Cockpit /
Trunk
a. All interior trim components such as carpets, seats, cargo bins, seat belts, floor mat, firewall insu- lation/blanket, sound deadener patches,
undercoating, radio systems, speakers, dome lights, grab handles, sun visors and their insulating and attaching materials, must be removed.
Other than to provide for the installation of required safety equipment or other authorized modifications, no other driver/passenger
compartment alterations or gutting are permitted.
b. It is permitted to install a radio replacement panel.
c. The outer edges of the dashboard may be cut the minimum amount required to install the roll cage.
d. Air bag systems must be disarmed and must be removed.
e. It is permitted to remove all components of the cruise control system.
f. The top portion of the door panels containing the door latch release handle must remain intact.
g. The lower portion of the door panels must be removed for installation of the roll cage. Gutting of the door may not go outside of the factory
seal.
h. The door window glass and window operating mechanisms must be removed.
i. The OE dashboard and its attaching hardware and brackets must be retained.
j. For installation of required safety equipment, however, it is permitted to modify the OE dash bar, so long as it is outboard of the first dash support
brackets (illustration below). Modification of the first dash support brackets, nor inboard from them, is not permitted. The OE dash bar must be
securely mounted.
k. The HVAC control module located under the dash may be removed together with the following: blower motor, evaporator core,
heater core and associated ducting. Once removed it is permitted to block the blower inlet passage on the firewall.
l. All openings between the driver/passenger compartment and the trunk / gas tank area that include the filler tube & fuel tank vent
must be filled completely with a metal bulkhead that is securely mounted (E.G. nuts/bolts, nut-serts, rivets). This shall close the
entire trunk from the driver/ passenger compartment and comply with current GCR Section 9.3.
m. Mazda Motorsports’ finish panel trim kit (part # 0000-07-5822) may be used to create the required bulkhead above
n. It is permitted to remove the driver’s side factory seat mounts, but not the floor pan.
o. It is permitted to remove the horn and all associated horn related components.
p. OE driver’s seat must be replaced with a one-piece bucket-type race seat per current GCR Section 9.3.
q. The passenger seat must be removed.
r. Any steering wheel except wood rimmed types may be used.
s. Any shift knob may be used.
t. The air conditioning equipment located in the engine compartment (AC compressor assembly, associated lines/dryer and the
condenser) must be removed.
u. Alternate gauges and instruments may be added. The original instrument cluster must remain connected and functional However,
it may be relocated to allow the mounting of an aftermarket dash such as an AiM. The wiring to relocate the dash may not be cut or
extended, it may only be re-routed. The remainder of the dashboard or panel must remain intact.
v. Modifications may be made to the foot pedals to improve the comfort and accessibility to the driver; relocation of mounting
points is not permitted.
1. Dead pedal/footrest and heel stop may be added.
w. Instrument clusters must be unmodified OE parts .
x. Two-way radios may be used.
y. Alternate means of windshield defrosting is permitted
6. Engine
Modifications
6.1. General
a. No modifications to the engine are permitted, except where specifically authorized within these rules. This includes but is not
limited to: all fuel injection and engine management components, as well as electrical, cooling, and lubrication systems.
b. All systems, unless otherwise stated, are subject to test procedures and must conform to OE
specifications as stated in the Mazda Factory Service Manual.
c. Permitted engine maintenance includes the replacement, but not modification, of external engine and engine systems parts.
1. No balancing, blue printing, lightening, polishing or other modification of moving parts of the engine is permitted.
2. All parts in the engine must be OE parts unless specified in this rule set.
3. For all Mazda part numbers in these specifications, superseding part numbers are consid- ered equivalent.
d. Compression ratio for 2.0L engines must be 11.00:1; calculated using the official Spec MX-5 calculator.
6.2. Engine Block
a. The engine block may be decked or milled to achieve the class specified compression ratio. Honing of cylinders is permitted to accommodate
piston clearance so long as a maximum standard diameter is not exceeded shown in Table 3.
b. The cylinders may be bored to accommodate piston clearance requirements so long as maximum permitted overbore diameter is not exceeded
shown in Table 3 below.
Table 3: Piston Sizes
Piston Part # Bore Diameter Max
Standard 0000-01-5310 87.6046mm (3.449”)
Allowed Overbore (.020) 0000-01-5310-OS 88.1126mm (3.469”)
c. It is not permitted to overbore a single cylinder; all cylinders must be bored equally.
d. Sleeving of cylinders is not permitted.
6.3. Crankshaft
a. OE Mazda MZR 2.0L (2009-2015) manual transmission crankshaft (part # LF9G-11-301) must be used with no modifications except for
machining or polishing polishing and/or machining of the bearing surfaces to allow the use of main and rod bearings as permitted
in Table 4 below.
Table 4: Crankshaft Measurements
easurement iameter Diameter
b. OE crankshaft (Mazda part # LF9G-11-301) must weigh a minimum of 31.75lb.
c. Maximum permitted stroke is as follows: 3.27” / 83.1mm
d. Shot peening is prohibited.
e. Bearings
1. Main and rod bearings must not be modified; coatings are not permitted.
2. OE bearings are permitted.
3. The only bearing sizes permitted other than OE are listed in see Table 5.
Sizes
Bearing Type Minimum Bearing
Width Minimum Bearing
Thickness Minimum Bearing
Weight Part #
Main Bearings
(Standard H) .630” 0.097” N/A 0000-01-5215-MB
Main Bearing
(Standard HX) .630” 0.097” N/A 0000-01-5216-MB
Rod Bearings
(Standard H) .630” 0.057” 28g 0000-01-5213-RB
Rod Bearing
(Standard HX) .630” 0.057” 28g 0000-01-5214-RB
f. The crank trigger must not be modified; it must be installed per the Mazda Factory Service Manual.
g. OE crank pulley/balancer (Mazda part # LF94-11-400) must not be modified and must be installed per the Mazda Factory Service Manual.
h. Knife edging of the crankshaft is not permitted.
i. Modifications to the crankshaft counterweights are not permitted.
j. Coatings, REM or metal treatments of any kind are not permitted.
k. Alternate shifter bushing located at the bottom of the shift lever is allowed.
6.4. Connecting Rods
a. OE Mazda MX-5 (2009-2015) manual transmission unmodified connecting rods (part # LF9G- 11-210) must be used. Connecting
rod weight with cap and bolts must not be less than 530 grams.
6.5. Pistons
a. Mazda Motorsports’ competition pistons (standard bore part # 0000-01-5310; oversized part # 0000-01-5310 OS) are required;
no modification is permitted.
b. The minimum weight of the piston, less wrist pin and hardware, must not be lighter than 290 grams.
c. Mazda Motorsports’ competition wrist pin (part # 0000-01-5310-PN) must be used.
d. The minimum weight of the wrist pin must not be lighter than 80 grams.
e. Modification of the piston ring end gap width is permitted.
6.6. Cylinder Head
a. Mazda Motorsports’ competition cylinder head (part # 0000-01-5300) must be used; no modi- fications to the cylinder head are
permitted outside of the gasket face surface outlined below in Table 6.
b. Intake runner CC volume is 182cc +/- 1cc.
c. Exhaust runner CC volume is 114cc +/- 1cc.
d. Combustion chamber volume may not be below 41cc.
e. The gasket face of the cylinder head may be resurfaced provided the maximum allowed compression ratio is not
exceeded.
I. Surfacing of the head gasket surfaced must be in a flat plane.
II. Cylinder head gasket surface distortion may not exceed .010mm or 0.004”.
f. The minimum height of the cylinder head as measured must be at least (TBA)
g. The following head gaskets in Table 6 below are permitted; no other gaskets may be used.
Table 6: Head Gasket Measurements
Description Thickness Mazda Part #
OE Gasket 0.017” approximate crush
depth L3G2-10-271A
Competition
Gasket 0.55mm (0.021”) 0000-01-5319-21
Competition
Gasket 0.75mm (0.030”) 0000-01-5319-30
Competition
Gasket 1.0mm (0.040”) 0000-01-5319-40
Competition
Gasket 1.3mm (0.051”) 0000-01-5319-51
6.7. Camshaft and Camshaft Timing
a. Camshafts must not be modified; see Table 7 for OE camshaft part numbers.
Table 7: Camshaft part numbers
Description Mazda Part #
Intake Cam L3E3-12-420
Exhaust Cam L309-12-441B
b. Camshaft and crankshaft sprockets must not be modified; see Table 8 for part numbers.
shaft Sprocket Part #s
t #
4X0C
425
c. Cam timing must not be altered; chain must be installed as stated in the Mazda Factory Service Manual.
d. OE timing chain (Mazda part # LF7A-12-201) is required; no modification is permitted.
e. OE timing chain components must be used; see Table 9 for Mazda part numbers.
Table 9: Timing Chain Guide Part #s
Description Mazda Part #
Fixed Guide LF01-12-614
Tensioner Guide LF01-12-671
6.8. Valves
a. OE valves must not be modified (including reshaping); see Table 10 for Mazda part numbers.
le 10: Valve Part #s
b. Valve location or angle must not be moved.
c. Valve guides may not be replaced.
d. Valve job measurements must be as follows:
1. Intake 35 top 45 seat 65 bottom 77 bottom seating angle width is 1.0mm
2. Exhaust 40 top 45 seating to radius seating angle width 1.2 mm.
3. Valve stem installed height must be per the Mazda Factory Service Manual.
4. Valve stem seals must be OE.
6.9. Valve Springs
a. Mazda Motorsports’ competition valve springs (part # 0000-01-5319-SP) are required.
6.10. Intake Manifold
a. OE intake manifold (Mazda part # LF9G-13-130B) is required; no modification is permitted (e.g., no material may be added or removed; no
painting or coating on the exterior or interior permitted).
b. All air entering the engine must pass through the throttle body and metered by the mass airflow sensor.
c. Removal of these factory EGR components is permitted: Valve, crossover pipe, coolant lines (EGR DELETE KIT 0000-06-5447)
d. If factory EGR components are removed, the following ports must be blocked:
1. Intake manifold cross over pipe port.
2. Cylinder head cross over pipe port.
3. EGR valve port on back of cylinder head.
6.11. Intake System
a. Cars must replace OE air box with the Mazda competition cold air intake kit (part # 0000-06- 5150-KT); no modification (e.g., ducting or
baffling of air, venturi cones) to the cold air intake kit is permitted.
b. No alteration to the intake tube length, diameter, or shape is permitted.
c. The air filter supplied in the Mazda Motorsports competition cold air intake kit may be refreshed
with the Mazda Motorsports’ competition air filter (part # 0000-06-5204).
6.12. Fuel System
a. Fuel must comply with SCCA GCR section 9.3.25
b. OE fuel pump (Mazda part # LFG1-13-350) is required; no modification is permitted.
c. It is permitted to remove the unleaded fuel restrictor from the filler neck. (GCR 9.3.26)
d. Mazda Motorsports’ competition fuel rail that includes fuel pressure gauge, and fuel sampling test port and hose kit (part #
0000-06-5207) is optional.
1. Fuel pressure sensor integrated into the required AIM data acquisition system is required. It must be operational and able to be
viewed when pulling a competitor on track data.
2. The addition of a switch or jumper located in the under-hood fuse box is allowed to acti- vate the fuel pump. This modification may
serve no other purpose.
3. One operational fuel sample test port is required. Fuel sample test ports shall be made from dry break fuel rated quick disconnects.
No other style of fuel sample test port is allowed (e.g., Schrader valves).
4. No other modifications permitted.
e. OE fuel pressure regulator (Mazda part # LFB6-13-280) is required.
1. Vehicle must run between 54 and 63 PSI of fuel pressure.
f. OE injectors (Mazda part # L3G5-13-250) are required; no modification is permitted.
1. Flow rates for the injectors must fall within the factory tolerance of 204-216ml (204-216 cc, 12.5-13.1 cu in/minute).
6.13. Lubrication System
a. OE engine oil filter is required; no substitutions permitted.
b. OE oil pump PT# L310-14-100J is required and no modifications are permitted.
c. Mazda Motorsports’ competition oil cooler adaptor kit with lines (part # 0000-01-5100KT) is required; no modification is
permitted.
d. Oil pressure sensor integrated into the required AIM data acquisition system is required. It must be operational and able to be
viewed when pulling a competitor on track data.
e. Oil and lubricants are unrestricted.
6.14. Engine Control Unit (ECU)
a. Reference penalties for non-compliance of the Spec ECU flash in Section 21 below. Modifica- tion or attempted modification of
the Spec ECU flash will result in a 12-month suspension from competition and $1,000.00 fine.
b. Mazda Motorsports’ competition ECU (part # 0000-01-5379) is required; serial number must be visible; external or internal
modification is not permitted.
c. ECU calibrations and inputs must not be modified.
d. OE engine electrical harness (part # NH18-67-020A) is required; no modification is permitted.
e. OBDII diagnostics port must be operational in all cars.
1. The check engine light must be operational and perform the function test at start up.
2. The OBDII port must be available at all times (including during the race) for tech officials to install test equipment as necessary.
3. If a competitor uses the OBDII port to power any type of data acquisition system, he/she would be responsible for providing the
splitter cable to plug in both units or unplug the data acquisition system.
f. Instrument panel clusters must be operational and unmodified OE parts.
g. Temporary data acquisition devices may be installed by the sanctioning body for technical compliance.
h. Removal of Mazda ECU insulator PT# LFG1-13-3C1 is permitted (diagram below)
6.15. Miscellaneous
a. The factory air conditioning system and all associated lines, compressor, condenser and evap- orator must be removed.
1. Once the AC compressor is removed, the OE AC pulley delete kit (Mazda part # LF17-15- 940E) is required.
b. Serpentine belt Gates PT# 6PK-2170 or same size equivalent is required.
7. Exhaust
a. OE exhaust manifold and OE heat shield must be replaced with Mazda Motorsports’ competi- tion part # 0000-06-5407-NC; no modification
is permitted (e.g., internal or external wraps, coatings, paints, metal treatments, thermal barriers etc.).
b. OE exhaust system must be replaced with Mazda Motorsports’ competition part # 0000-06- 5427-NC; no modification is permitted (e.g.,
internal or external wraps, coatings, paints, metal surface treatment, thermal barriers etc.).
c. The forward oxygen (O2) sensor (OE Lambda Sensor) must remain in the factory location and in full working order. Mazda Motorsports’
competition O2 sensor installation kit wiring extender (part # 0000-10-5320) is permitted.
d. The secondary post catalytic oxygen (O2) sensor must be removed.
e. Heat shielding
1. OE heat shield protecting ABS unit from header may not be removed or modified.
2. OE muffler heat shield may not be removed or modified.
3. It is permitted to wrap the exhaust pipe from the mid connection flange to the muffler.
(see red arrows in picture below)
4. Use of heat shielding material on transmission tunnel to replace OE heat shielding is permitted. OE heat shielding
must be removed from transmission tunnel. (see diagram below)
8. Cooling System
(cooling system
checklist)
a. Mazda Motorsports’ competition radiator and oil cooler assembly (part # 0000-01-5504-CR) is required (e.g., OE is not
permitted).
b. The radiator using the OE mounting brackets must be installed in its original location.
c. The oil cooler may not be moved or altered from the pre-assembled mounting location.
d. Radiator ducting may be placed on each side of the radiator tanks and the undertray to force air through the radiator fins. The
gap between the top and sides of the radiator may be sealed but shall not perform any other function.
e. The unmodified OE cooling fan must be maintained in full working order and mounted in the stock location. Axillary control of
the radiator cooling fan may be added to activate the fan independent of the ECU, OE control of the fan must remain intact.
f. Thermostats may be modified, removed or replaced.
g. The OE water pump (Mazda part # 1F70-15-100) is required; no modification is permitted.
h. The OE water pump pulley (Mazda part # L327-15-131) is required; no modification is permitted.
i. Engine cooling system hoses and clamps may be substituted.
j. The heater core may be removed along with HVAC evaporator core including all associated hard pipes and hoses. This is to include
OE water to oil cooler lines as well as throttle body coolant lines. (Rear coolant pipe 0000-01-5514, bottom coolant pipe 0000-
01-5515)
k. The OE engine coolant expansion tank may be replaced with any aftermarket part but and must not serve another purpose.
9. Clutch, Pressure Plate and Flywheel
a. Vehicle may use any combination of the options listed in Table 11 below.
Table 11: Clutch Component Part Numbers
Description Mazda Part #
Mazda Factory Clutch Disc LF05-16-460A
ACT Sprung Clutch Disc 0000-02-5420-AC
ACT Pressure Plate 0000-02-5405-AC
ACT Clutch and PP Kit 0000-02-5004-G6
Mazda Factory
Pressure Plate LF04-16-410A
b. The unmodified pressure plate must be bolted directly to the stock, unmodified flywheel.
c. OE flywheel (Mazda part # LF9G-11-500) is required. Factory Service Manual resurfacing specification is permitted; no
other modification is permitted.
d. Alternate clutch lines are permitted but must not serve another purpose.
e. Clutch components must adhere to the minimum weights listed in Table 12 below:
Table 12: Clutch Component Part Numbers
Description Minimum Weight (lb.)
Clutch disc 3.5
Pressure Plate 9.4
Flywheel 15.80
10. Transmission
a. OE 2006-2015 6-speed gearbox and 4.10 final drive ratio are required.
b. No modification of the internal parts and ratios are permitted except the installation of the unmodified parts contained in the Mazda
Motorsports MX-5 transmission upgrade kit (part # 0000-02-5700).
c. Mazda Motorsports Competition gear set 0000-02-6000 is allowed. Gear ratios are as follows: 1st - 3.82; 2nd - 2.26; 3rd - 1.64;
4th - 1.18; 5th - 1.00; 6th - 0.83/0.79. There are two (2) production 6th gears; either one is permitted.
d. Alternate shift knobs are permitted.
e. Nomex or aftermarket fireproof shift boots are permitted. Removal of the factory rubber shift boot is not permitted.
f. No treating, coating, polishing or modification of any transmission or components are permitted.
g. Fluids and/or lubricants may be substituted with any lubricant.
h. Updating or backdating of transmissions from 2006–2015 is permitted; unmodified OE shifters must be retained. The use of short throw
shifters is prohibited.
i. An single inspection hole (not to exceed 1.5” in diameter) in the bottom of the bell housing is permitted for the sole purpose of technical
inspection of the flywheel. It is permitted to plug or tape over theat hole.
j. Transmission cooler(s) are permitted.
11. Differential
a. Only the Following differentials are allowed.
1. Mazda Motorsports, unmodified, Torsen limited slip differential – 0000-02-5564
2. OE, unmodified, limited slip differential - Mazda part # MS03-27-200B
3. OE, unmodified, open differential are permitted.
b. RX-8 differential mounting bracket (Mazda part # F151-39-730B) is permitted.
c. Mazda Comp diff bushings 0000-04-5510 is permitted (MX-5 diff mount)
d. Polishing, metal treatment or coating of differential or axle components are not
permitted.
e. Removal of metal/rubber isolator on the pinion flange is permitted.
f. Differential cooler(s) are permitted.
12. Suspension and Steering: Suspension
Modifications are limited to the addition of the Mazda Motorsports Spec MX-5 kit; details are as follows (including all
modifications permitted):
a. OE control arms are required; no modification is permitted.
b. Mazda Motorsports’ TSB MX-5-002 must be followed re: the rear shock thread protector found in the “Spec MX-5: Four Pillars”
page on MazdaMotorsports.com. The thread protector must measure 1.250”. (The TSB will not be applicable to the supply from
Mazda Motorsports received after 7.15.2020 as they will have the updated thread protector.)
c. Anti-roll bar links may be replaced with Mazda part # 0000-04-5597-KT
1. Cockpit adjustability is not permitted.
d. Mazda Motorsports’ competition sway bars are required, mounting guidelines:
1. Metal shims up to 1/8” total thickness are permitted between each anti-roll bar mount shackle and the stock mounting
point on the chassis.
2. One end of the sway bar(s) may be disconnected as a suspension tuning aid.
3. The bar must remain in place and be solidly attached to the suspension on one end.
4. Sway bar end links must be installed on the unmodified stock attachment points.
e. Camber, caster, and toe are unrestricted within the limits of the unmodified factory adjust- ments in conjunction with Mazda
Motorsports front offset bushing (part # 000-04-5407-NC).
f. Minimum ride height is unrestricted.
g. Nuts & bolts may be replaced by similar items performing the same fastening function(s).
h. Relocation or reinforcement of any suspension parts or mounting points is not permitted, with the following exceptions:
1. Addition of spacers or washers on a horizontal plane is permitted at the rear lower shock mount to the spindle per the
shock installation instructions.
2. Updating to RX-8 rear toe link and rear trailing arm is permitted. See Table 13 below.
Table 13: Permitted RX-8 Trailing Arm and Toe Link Part #s
Description Mazda Part #
RX-8 Trailing Arm F189-28-200A
RX-8 Toe Link F189-28-45XA
i. OE power steering pump with pulley (Mazda part # NE51-32-650D) is required; Mazda Motor- sports Power steering flow
restrictor PT#- 0000-04-5532 is permitted; no other modification is permitted.
j. OE power steering rack (Mazda part #: NE51-32-110C) is required; no modification or reloca- tion is permitted.
k. Factory power steering reservoir may be replaced.
l. Wheel center caps must be removed.
m. All chassis, structural and electrical repairs must follow factory procedures, specifications, and dimensions as described in the
applicable service manual. Reinforcement (e.g., seam welding, material addition, etc.) is not permitted.
n. Steering lock mechanisms must be removed.
o. The distance from the outside of the wheel rim to outside of the opposing wheel rim for both the front and rear of the vehicle
must not exceed 69.5”.
I. The distance Measurement is obtained by measuring the distance between the wheel lips by going through
the wheel spokes at the bottom of the wheel at its widest point via tape measure. (Measure the outside wheel
lip of one wheel to outside wheel lip of the other wheel on same axle.)
p. Mazda Motorsports’ competition rear toe link (part # 0000-04-5426) is permitted; no modification is permitted.
q. Mazda Motorsport’s Spec MX-5 Suspension Kit includes the items set forth in Items in Table
14. seen below are components within this kit. No substitutions or modifications of parts are permitted. The
unmodified kits must be used in their entirety, except as specified.
Table 14: Spec MX-5 Suspension Kit (All parts are required; no modification is permitted.)
Description Location Mazda Part #
Shocks Front 0000-04-5291-SA
Rear 0000-04-5292-SA
Springs Front 0000-04-9700-08
Rear 0000-04-9400-07
Helper Springs Front/Rear 0000-04-9926
Front Penske
Mount Kit Front 0000-04-5359
Rear Penske
Mount Kit Rear 0000-04-5358
Sway Bar Kit Front and Rear 0000-04-5306-EB
Offset Bushings Front 0000-04-5407-NC
13. Hubs
a. OE RX-8 front hub (Mazda part # F189-33-04X) may be substituted in place of the OE Miata 2006-2015 front hub.
b. Mazda Motorsports’ competition RX-8 rear hub upgrade kit (part # 0000-04-5811-KT) may be substituted in place of the OE MX-
5 rear hubs; this unmodified kit must be used in its entirety.
c. OE RX-8 rear uprights, bearings, hubs, and hybrid axel may be used in place of OE MX-5 parts.
14. Brakes
a. OE brake rotors must be used and adhere to the specifications below in Table 15.
Table 15: Brake Rotor Dimensions
Location Diameter Notes
Front 290mm (11.4”) Vented
Rear 280mm (11.0”) Solid
Front backing plates/dirt shields may be removed.
(see see red arrow in diagram below)
b. Rear backing plates/dirt shields may be removed.
(see red arrow in diagram below)
c. Brake lines may be replaced with competition braided steel lines; option: Mazda Motorsports’ part # 0000-03-5212.
d. The Factory ABS system must remain intact, unmodified, and in full working order.
e. Brake slider pin may be used in either/both front location B25D-33-694. (This prevents a stuck sliding caliper due to the rubber
grommet)
f. Parking brake mechanisms and actuating components may be removed.
g. Brake fluid is unrestricted.
h. Mazda Motorsports’ competition brake duct kit (part # 0000-03-5301) is permitted.
i. The forward vertical inner fender panels may be modified to fit the brake kit hose to the fog light openings but may not be
modified to serve any additional purpose.
j. Mazda Motorsports’ competition brake pads are required; see eligible brake pad compounds in Table 16. No other brake pads
are permitted.
Table 16: Brake Pad part numbers
Pad Style Mazda Part # Notes
Front Pad 0000-03-5104-SP RST-3 compound
Rear Pad 0000-03-5116-29 RSL-29 compound
15. Wheels
The following unmodified wheel options below in Table 17 are permitted for use.
Table 17: WHEELS
Description Color Mazda Part #
17x7” OE Wheel Gun Metallic 99656-47070
17x7” OE Wheel Silver 99656-77070
Mazda Motorsports’ Competition MX-5 Wheel Gun Metallic 0000-04-5706-GM
Mazda Motorsports’ Competition MX-5 Wheel Silver 0000-04-5706-SL
a. Wheels may be painted.
b. Aftermarket (any) wheel studs and lug nuts are permitted., provided that a minimum of two he threads must protrude
beyond the lug nut with the wheel installed with a minimum of two (2) full threads showing; Wheel studs may not be gun
drilled.
c. Wheel spacers are not permitted.
16. Tires
a. Dry tires: Toyo RR P235/40/ZR17
b. Wet tires: Toyo RA1 P235/40/ZR17.
17. Electrical Equipment
a. OE ignition coils (Mazda part # L3G2-18-100B) are required; no modification is permitted.
b. Mazda’s competition spark plugs (part # 0000-10-R7IX-11) are required; no modification is permitted.
c. The crankshaft position sensor and crankshaft pulley relationship must be as specified in the 2006- 2015 MX-5 Factory Service Manual.
d. One of the two OE alternators (Mazda part # LF9H-18-300R-OA, L3P9-18-300D) is required; no modification is permitted.
e. The alternator must not be externally regulated or disabled in any way other than by the OE
production ECU/wiring circuit and master kill switch.
f. The electronic control module (ECM) control circuit for alternator charging must be OE - unmodified and operational.
g. One of the two OE alternator drive pulley part # AJ51-18-W10 (60mm), Part# L813-18- W11(55mm) is required; no modification
is permitted.
h. All sensors related to engine operating parameters must be used and must be stock, unmodi- fied Mazda parts for the correct year
of the vehicle on which they are installed.
i. Any and all sensors and their respective locations, mounts, and wiring harness leads may not be altered except as elsewhere in this
rule set. e Spec-MX-5 rules.
j. Any sensors required for non-OE gauges must be in addition to the Mazda sensors.
k. All alternate gauge and sensors must have independent wiring. Splicing, tapping, or altering
of the factory engine wiring harnesses is prohibited with the exception of adding an
aftermarket tachom- eter/shift light as follows:
1. It is permitted to splice into the yellow wire with the black stripe (pin 2BA - Ignition
Coil 1 control circuit) in the engine harness to obtain the tachometer signal for an
aftermarket tachometer or shift light.
2. Splicing must be done within 5” of the ECU.
l. Data acquisition’s sensor(s) may be added, provided they do not require splicing or
alteration to the factory engine wiring harness.
m. Batteries
1. Batteries may be replaced with those of an alternate manufacturer, provided they are of
similar amp-hour capacity, and size, including lead acid or AGM.; lLithium batteries are not
permitted.
2. Batteries must weigh no less than 18.0lb and no more than 35.0lb
3. Additional battery hold-down devices are recommended.
4. Battery MUST be moved from the original location to the passenger side
in the upper trunk area in front of the tail lamp. This will require the use
of a bulkhead that separates the driver / passenger compartment
completely from the trunk and the battery location. See section 5.I for
reference.
18. Roll Cage
a. Roll cage must adhere to SCCA’s current GCR Section 9.4 for Touring 4 cars; with the following exceptions:
1. One tube not to exceed 1.75” in diameter may be added which extends from the door bars to the rocker panel on each side.
The landing plate for this tube can be no longer than 5” in length. The landing plates must be centered between the front
and rear landing plates for the lower NASCAR or X brace bar.
2. Main hoop mounting plates may be on multiple planes; however, they must not be greater than 19” on any side.
b. Playboy MX-5 Cup car cages manufactured by Racing Cages, Inc. with the official serial number plate on the main hoop are
allowed to retain the lower door bar and two 3” attachment points to the rocker panel on both the driver’s side and passenger
side. No additional seam welding or lengthening of the original attachment points is allowed.
19. Safety
a. An electrical master (“kill”) switch is required. See current GCR Section 9.3 Master Switch.
b. Vehicle must be equipped with a driver’s restraint system meeting the specifications of current GCR Section 9.3 Drivers
Restraint System.
c. Installation of a fire extinguisher or fire system is required. See current GCR 9.3 Fire System.
d. Vehicle must have a driver’s side window safety net complying with current GCR Section 9.3 Window Safety Nets. Nets must be
mounted to provide protection in the event the driver’s door opens.
20. Data
Acquisition
1 A technical evaluation process for cars is available from the Series. Part of this process is the required download of AiM Data files after
each timed session (Qualifying 1 & 2, Races 1 & 2). Within 30 minutes of each timed session end, all Series Competitors MUST send
the AiM Data file (.XRK) for all timed laps of that session to the secure email address (data@specmx-5.com), where data will be
reviewed by AiM directly. Failure to adhere to this guideline from the Series, or having non- functioning data, may be grounds for
penalty or disqualification by the Series.
a. Vehicle must be equipped with current generation AiM data acquisition system (configurable in Race Studio 3) that can provide
on track data to AiM race studio 3. The data acquisition system may only read the OBDII/ECU data stream. It is not permitted
to alter/manipulate data to and from the ECU. The AiM system may be utilized to trigger a switch I.E., cooling fans or diff cooler
pumps but must be wired via a separate analog circuit.
Refer to Section 17: Electrical Equipment above for installation requirements.
b. The connection at the OBDII port for the AiM system may be made in either one of two ways:
1. Through a dedicated OBDII AiM adaptor.
2. By direct wiring to the back of the OBDII port within 3” of the ODBII connector.
c. Fuel pressure datalogging is required.
d. Oil pressure datalogging is required.
e. All cars must run the latest AIM Data Logger Spec MX-5 ECU Protocol
21. Mandatory
Video
Camera
Cars running in Spec MX-5 must have a functioning video recorder/camera during all qualifying and race sessions as described in 9.3.11.
Upon request by an SCCA official, competitors must provide their video recording/data, which may be used by the SCCA for any
purpose including but not limited to rule enforcement and marketing. Failure to comply with a video request from an official, or
having a non-functioning video recorder/camera may will be grounds for penalty or disqualification.
22. Parts
Confiscation
a. Tech officials may confiscate competitors’ parts for the purpose of verification of tech compliance.
23. Penalties Clarification – Non-Compliant Parts
Level Infraction Penalty
1 Non-compliant modification to any of the spec
parts, engine components, ECU/Elec- tronics or
modification to the chassis.
May suspend the driver (i.e. suspend) of the non-
compliant Spec MX-5 from competing in SCCA
events for the 12 months following the suspension.
A level 1 infraction carries a $1,000 fine.
2
Non-compliant modification to the suspen- sion or
drivetrain outside of level one infrac- tions: engine,
fuel system, charging system, exhaust, and intake
system.
May suspend the driver (i.e. suspend) of the non-
compliant Spec MX-5 from competing in SCCA
events for the 6 months following the suspension.
A level 2 infraction carries a $500 fine.
3 Use of an unauthorized or non-compliant part,
engine component, ECU/Electronics or chassis or
chassis part.
May suspend the driver (i.e. suspend) of the non-
compliant Spec MX-5 from competing in SCCA
events for the 12 months following the suspension.
A level 3 infraction carries a $1,000 fine
4
Non-compliance (non-modification such as
incorrect part)Use of an unauthorized or non-
compliant for any of the suspension or drive- train
part or component outside of level one infractions:
engine, fuel system, charging system, exhaust, and
intake system.
May suspend the driver (i.e. suspend) of the non-
compliant Spec MX-5 from competing in SCCA
events for the 6 months following the suspension.
A level 4 infraction carries a $500 fine

SM Committee) OE versus OEM Definitons

#36608 from Spec Mazda (SM/SMX · Rule change · TB 24-09 (2024-09 Fastrack)

neutralSMX Mazda Miata OE versus OEM definitions clarified in GCR Section 9.1.7.1.

In GCR, Replace Section 9.1.7.1 Spec MX-5 (SMX) with the attached:

SM Committee) Shifter Bushing

#36611 from Spec Mazda (SM/SMX · Rule change · TB 24-09 (2024-09 Fastrack)

neutralSM and SMX shifter bushing rules clarified: alternate bushing at shift lever bottom now allowed.

In section 9.1.7.1.D.6.3., add the following:
"k. Alternate shifter bushing located at the bottom of the shift lever is allowed."

HP 1275 HP Spridget Level 2 Only

#36518 from Darryl Saylor · Rule change · TB 24-09 (2024-09 Fastrack)

fasterHP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1.

In HP Spec Lines, Austin-Healey Sprite MkI, II, III, IV MG Midget (ALL) - Level 2 - 1275cc, change Notes as follows:
"(Effective 11/1/2024) Compression ratio limited to 11 12.0:1"
In HP Spec Lines, Austin-Healey Sprite MkI, II, III, IV MG Midget (ALL) - Level 2 - 1098cc, change Notes as follows:
"(Effective 11/1/2024) Compression ratio limited to 11 12.0:1"

HP Request for Classification of 1989-1994 Suzuki Swift GT 16V Twin

#36858 from Jorge Fabian · Rule change · TB 24-11 (2024-11 Fastrack)

neutralSuzuki Swift GT 89-94 newly classified to HP Pre at 1900 lbs, 1298cc DOHC fuel injected.

In HP Spec Lines, Classify Suzuki Swift GT (89-94) as follows:

A specification table follows in the original; it is not shown here.

T4 Bop Request 06-11 Honda Civic Si

#37013 from Mathew Milford · Rule change · TB 24-11 (2024-11 Fastrack)

neutralT4 Honda Civic Si 06-11 permitted to use LSD per category rules.

In T4 Spec Lines, Honda Civic Si (06-11), add to Notes the following:
"LSD is permitted according to category rules."

T1 Changes to T1 Tires for GT4 and Other Cars

#35383 from Andrew Aquilante · Rule change · TB 24-12 (2024-12 Fastrack)

unclearT1 GT4 tire sizes adjusted across ten cars: most non-DOT rear to 305/660, Audi and McLaren 305/645, Camaro and Mustang 305/680.

In T1 GT4 Spec Lines, change Tire Size as follows:
Aston Martin Vantage AMR GT4 4010: "315 DOT, 305/660 Non-DOT"
Audi R8 GT4 - Spec Line #4020: "315 DOT, 305/645 Non-DOT"
BMW M4 GT4 - Spec Line #4030: "315 DOT, 305/660 Non-DOT"
Chevrolet Camaro GT4-R- Spec Line #4035: "315 DOT, 305/680 Non-DOT"
Ford Mustang GT4 - Spec Line #4040: "315 DOT, 315/680 Non-DOT"
Mclaren 570S GT4 - Spec Line #4050: "315 DOT, 305/645 Non-DOT"
Mercedes AMG GT4 - Spec Line #4060: "315 DOT, 305/660 Non-DOT"

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Porsche 718 Cayman GT4 CS MR - Spec Line #4070: "315 DOT, 305/660 Non-DOT"
Porsche 718 GT4 RS Clubsport - Spec Line #4080: "315 DOT, 305/660 Non-DOT"
Toyota Supra GR GT4 - Spec Line #4090: "315 DOT, 305/660 Non-DOT"

T1 G82 M4 GT4 inclusion in T1

#35864 from Denny Stripling · Rule change · TB 24-12 (2024-12 Fastrack)

neutralBMW M4 GT4 (G82) added to T1 GT4 at 3525 lbs minimum weight with Red power stick control.

In T1 GT4 Spec Lines, SL#4030, change as follows:
Model: "BMW M4 GT4 (F82)"
Performance Control: "Gold power stick Red power stick"
In T1 GT4 Spec Lines, classify BMW M4 GT4 (G82) as follows:

A specification table follows in the original; it is not shown here.

T4 Redundant Verbiage Regarding Mustang Spec Lines for Driveshaft

#36484 from David Mead · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT2 and T3 Mustang spec lines remove redundant driveshaft alternate/aluminum allowance wording.

In T2 Spec Lines, change Notes as follows:
Ford Mustang V6 (11-14): "Alternate driveshaft is allowed."
Ford Mustang Boss 302 (12-13): "Alternate driveshaft is allowed."
Ford Mustang GT 5.0L (11-14): "Alternate driveshaft is allowed."
Ford Mustang GT 5.0L (15-17): "Alternate driveshaft is allowed."
Ford Mustang GT 5.0L (2018-): "Alternate driveshaft is allowed. Springs up to 800#/in front and rear permitted. Alternate
metallic driveshaft permitted."
Ford Mustang Coupe GT & Shelby GT 4.6L (05-10): "Alternate driveshaft is allowed."

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In T3 Spec Lines, change Notes as follows:
Ford Mustang Coupe GT & Shelby GT 4.6L & Cal. Special (05-10): "Alternate driveshaft is allowed."
Ford Mustang V6 (11-14): "Alternate driveshaft is allowed."
Ford Mustang V6 (05-10): "An Aluminum driveshaft is allowed."

T1 Alt. Clutch Allowance

#36606 from Hugh Stewart · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT1 Spec Lines now permits 5.5 inch clutch in Engine Notes.

In T1 Spec Lines, SL# 1050, change add to Engine Notes the following:
"5.5 inch clutch permitted."

T4 R53 Mini Cooper S Weight Reduction Request

#36612 from Manvinder Singh · Rule change · TB 24-12 (2024-12 Fastrack)

fasterT4 Mini Cooper S R53 now allows Alta 15% Pulley #AMPENG20X.

In T4 Spec Lines, Mini Cooper S R53 (02-06), add to Notes as follows:
"Alta 15% Pulley #AMPENG20X allowed."

T1 BOP Changes Need Updates

#36667 from Joe Rainey · Rule change · TB 24-12 (2024-12 Fastrack)

fasterT1 GT4 Spec Line 4020 restrictor opens from 44mm to 45mm, minimum weight drops to 3400 lbs.

In T1 GT4 Spec Lines, Spec Line 4020, change as follows:
Performance Control: Power level 2020, 44mm 45mm SRO compliant restrictor"
Min. Weight with driver (LBS): "3550 3400"

T4 Allowable Wheel Offset

#36855 from Robert Maples · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT4 removes restriction on aftermarket wheel weight minimum of 15 lbs.

In GCR Section 9.1.9.2.D.7. Wheels and Tires, change as follows:
"a. Wheels
1. Any type wheel suitable for competition may be used, provided:
a. Any wheel not exceeding the specified diameter and rim width on the vehicle’s specification line may be used. Each wheel,
measured without weights, must weigh at least 15 lbs.
b. Wheels are permitted any offset provided the tire tread (that portion of the tire that contacts the ground) does not protrude
beyond the fender opening when viewed from 9.1.9.2.Touring (T2-T4) Category Specifications GCR - 660 the top perpendicular
to the ground, unless specified differently on the individual spec line for that car. To determine compliance the vehicle should be

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rolled through a powdered substance, as raced with driver, in order to indicate the tire tread contact patch under static
conditions. When a maximum tire size is listed on a vehicle’s specification line, aspect ratio is open and any tire may be used that
does not exceed the stated maximum section width.
c. Cars equipped with lug bolts may convert to wheel studs and lug nuts.
d. Wheel studs may be replaced with longer studs as necessary to fit optional wheels. Wheel spacers may be used for purposes
of adjusting track.
e-T4 only: (unless specified on spec line) Any aftermarket wheel with a minimum weight of 15 lbs allowed."

SM E&O SMX Regs 9.1.7.1.D.5.u-.w

#37070 from Greg Amy · Rule change · TB 24-12 (2024-12 Fastrack)

neutralSMX allows OE instrument cluster relocation for aftermarket dash mounting, with wiring re-routed only; alternate gauges now permitted.

In GCR, Section 9.1.7.D.5.u-w, change as follows:
"u. Alternate guages and instuments may be added. The original OE instrument cluster must remain unmodified, connected and
functional. However, it may be relocated to allow the mounting of an aftermarket dash such as an AIM. The wiring to relocated
the dash may not be cut or extended, it may only be re-routed. The remainder of teh dashboard or panel must remain intact.
v. Alternate gauges and instuments may be added.
w. Modifications may be made to the foot pedals to improve the comfort and accessibility to the driver; relocation of mounting
points is not permitted.
1. Dead pedal/footrest and heel stop may be added.

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w. Instrument clusters must be unmodified parts."

T4 Fuel Emissions Components

#37076 from Derrick Ambrose · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors.

In GCR, Section 9.1.9.2.D.1.c. add the following:
"5. Removal of ancillary fuel tank equipment charcoal canisters, emissions valves, and sensors allowed for OEM or aftermarket
fuel cell installations."

T4 2019-2024 Mazda 3 for T4

#37077 from Derrick Ambrose · Rule change · TB 24-12 (2024-12 Fastrack)

neutralMazda 3 (19-24) newly classified in T4 at 2850 lbs with 17×8 wheels and 245 tires.

In T4 Spec Lines, classify Mazda 3 (19-24), as follows:

A specification table follows in the original; it is not shown here.

T4 fix brake wording

#37129 from Touring Committee · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT2, T3, T4 brake component wording clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter.

In GCR, Section, 9.1.9.2.D.6. Brakes, change as follows:
"a. Components
1. The make and material of brake pads and linings may be changed.
2. Brake fluid may be substituted with any brake fluid.
3. Brake rotor dust shields may be removed or replaced to accommodate brake ducts.
4. Flexible rubber brake lines may be replaced with Teflon lined, metal braided hoses.
5. Any brake ducts are permitted, but they must serve no other purpose. Fender liners may be modified solely for routing and
attachment of brake ducts. Duct intake openings may be created by the opening of 2 sections up to 14.5 square inches each in

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the front fascia. The stock headlamp location is not permitted for brake ducting. Two alternative duct openings may be created
by the removal of the fog lights or 2 sections up to 14.5 square inches each of stock false grills originally located in the front
fascia.
6. Stock replacement brake rotors may be obtained from sources other than the manufacturer provided they are the exact
equivalent of the stock rotors. In T2 only - 2-piece rotors with ferrous metal rotor disks and aluminum hats are allowed, must be
within 5% of OE diameter. In T3 only - 2-piece front rotors with ferrous metal rotor disks and aluminum hats are allowed, must
be within 2% of OEM diameter. Drilled and slotted rotors are permitted.
7. Parking brakes, mechanisms, and actuating components may be removed.
8. Brake vacuum reservoirs sized 0.50 gallons or smaller are permitted. The port or fitting at the vacuum source may not be
modified, enlarged or relocated. The vacuum reservoir and brake booster must be a closed system."

T4 Evaporative emissions systems

#37130 from Touring Committee · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT2, T3, T4 fuel cell cars may remove charcoal canisters, emissions valves, and sensors.

In GCR, Section, 9.1.9.2.D.1.c., add the following:
"5. Removal of ancillary fuel tank equipment; charcoal canisters, emissions valves, and sensors allowed for OEM or aftermarket
fuel cell installations."

T1 Request Ford Performance Darkhorse R in T1

#37136 from Christopher Childs · Rule change · TB 24-12 (2024-12 Fastrack)

neutralMustang Darkhorse R added to T1 homologated cars at 3,250 lbs minimum with 305/315 tires, ineligible for Runoffs until 3 Super Tour events.

In T1-Homologated Cars Spec Line, classify Mustang Darkhorse R (Mustang Challenge) as follows:
T1 – Homologated Cars

A specification table follows in the original; it is not shown here.

T4 Allow Spec MX5 upgrade kit for 2009-11 RX8 S2 Transmision

#37140 from Chris Braunlich · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT3 and T4 Mazda RX-8 and MX-5 permit transmission kit #0000-02-5700.

In T4 Spec Lines, add the following to Notes:
Mazda RX-8 Base/R3/Sport/ GT (04-12): "Transmission kit # 0000-02-5700 permitted.
Mazda MX-5 / Club Model (06-15): "Transmission kit # 0000-02-5700 permitted."
In T3 Spec Lines, add the following to Notes:
Mazda MX-5 / Club Model (06-15): "Transmission kit # 0000-02-5700 permitted."
Mazda RX-8 Base/R3/Sport/ GT (04-12): "Transmission kit # 0000-02-5700 permitted."

T4 Move Spec Boxster to T4

#37158 from Rob Piekarczyk · Rule change · TB 24-12 (2024-12 Fastrack)

neutralPorsche Spec Boxster moves to T4, minimum weight 2750 lbs, requires 3 Super Tour events before Runoffs eligibility.

In T4 Spec Lines, classify Porsche Spec Boxster, as follows:

A specification table follows in the original; it is not shown here.

Applies to Porsche Boxster on this page: Lynne Griffiths

T1 Car Mods for T1 Corvette under line item 1150

#37173 from Thomas Napolitano · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT1 Corvette may roll or flatten wheel opening lips for tire clearance; plastic fenders may remove lips if edge thickness matches basic material.

In GCR, Section 9.1.9.1.A.2,, add the following:
"It is permitted to roll under or flatten any interior lip on the wheel opening for tire clearance. Cars with plastic/composite
fenders may remove any interior wheel opening lip, but the resulting material edge shall be no thinner than the basic fender
material thickness. Non-metallic inner fender liners may be removed. Vents may be added to fenders."

HP MINI Cooper Spec Line Correction - Rear Brake Rotor Diameter

#37176 from Robert Bax · Rule change · TB 24-12 (2024-12 Fastrack)

neutralHP Mini Cooper 02-06 rear brake rotor increases from 239/9.4 mm/in to 259/10.2.

In HP Spec Lines, Mini Cooper (02-06), change Brakes Std.mm/(in.) as follows:
"(F) 276/(10.9) Vented Disc (R) 239/(9.4) 259/(10.2) Solid Disc"

Applies to Mini Cooper on this page: Tom Tuttle

T4 3.7 Mustangs to T4

#37188 from Scotty B White · Rule change · TB 24-12 (2024-12 Fastrack)

neutralFord Mustang V6 (05-14) newly classified to T4 with 50mm restrictor, 3400 lbs minimum weight.

In T4 Spec Lines, classify Ford Mustang V6 (05-14), as follows:

A specification table follows in the original; it is not shown here.

T4 BMW 320i Spec Line

#37204 from chi ho · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT4 BMW 320i 14-15 Spec Line expires 12/31/24 removed; Turner Motorsports intercooler #024703TMS02 allowed.

In T4 Spec Lines, BMW 320i (14-15), change Notes as follows:
"**This Spec line will expire 12/31/24, Please submit to appeal** Turner Motorsports intercooler #024703TMS02 allowed."

T4 MX5 2006-2015 NC Help

#37221 from Richard Mooney · Rule change · TB 24-12 (2024-12 Fastrack)

unclearUnable to summarize: rule changes specified in letter #37281, not provided.

Thank you for your letter. Please see changes in letter #37281 in current Fastrack.

T4 Classification for a 2005 Cadillac CTS 3.6 liter 6 speed manual

#37224 from Timothy Nash · Rule change · TB 24-12 (2024-12 Fastrack)

neutralCadillac CTS 02-07 3.6L classified in T3.

In T3 Spec Lines, classify Cadillac CTS (02-07) as follows:

T4 Civic SI in T4

#37248 from Touring Committee · Rule change · TB 24-12 (2024-12 Fastrack)

fasterT4 Honda Civic Si 06-11 minimum weight drops 50 lbs to 2900, restrictor clarified.

In T4 Spec Lines, Honda Civic Si (06-11), change as follows:
Required Restrictor: "55mm flat plate restrictor required."
Min Weight: "2950 2900"
Notes: "The following items must remain stock: transmission differential - unless specified below. 55mm flat plate restrictor
required. LSD IS PERMITTED ACCORDING TO CATEGORY RULES"

T1 Increased Bore Throttle Bodies for E46 M3 S54 Engine

#37273 from Mark Pfeffer · Rule change · TB 24-12 (2024-12 Fastrack)

fasterT1 E46 M3 S54 can now use Dinan Throttle Body #D760-3400 on 3.250L engine.

In T1 Spec Lines, E46 M3 Spec Line # 1050, add to Engine Notes the following:
"Dinan Throttle Body #D760-3400 allowed on the 3.250L."

T4 2006-2015 T4 NC Mx5 spec line

#37278 from Touring Committee · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT4 NC MX-5 06-15 removes SM5 suspension allowance, clarifies Mazda Motorsports LSD part number, adds weight penalty for other LSDs.

In T4 Spec Lines, Mazda MX-5 / Club Model (06-15), change Notes as follows:
"Factory bolt-in roll bar/cross member may be removed to facilitate roll cage installation. MSR option permitted. Suspension
package permitted with a 100 lbs. weight increase that includes the following parts: front spring mount PT#-0000-04-5259, front
springs #0000-04-9700-08, rear spring mount PT#-0000-04-5258, rear springs #0000-04-9400-07, helper springs #0000-04-HLPR-
EB (optional), Swaybar kit – PT#-0000-04-5306-EB that includes (front sway bar kit PT#0000-04- 5306-FT, rear sway bar kit PT#-
0000-04-5306-RR), offset front camber bushing PT#-0000-04- 5407-NC. Mazda Motorsports cold air intake part #0000-06-5150-
KT allowed. Mazda Motorsport RX8 rear Hub Conversion kit part number 0000-04-5811-KT allowed, RX8 front hubs PT# F189-33-
04X allowed. The SM5 suspension (only) is allowed with a 100 lbs. weight increase. Allow Mazda header part numbers 0000-06-

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5407 or 0000-06-5407-NC. Any OEM or aftermarket hardtop is permitted that retains the OEM roof silhouette, including Mazda
hardtop and part #0000-07-5901- CC. Aftermarket power steering reservoir is allowed. Mazda Transmission kit part # 0000-02-
5700. Mazda Motorsports LSD #3265 5 0000-02-5564 permitted without penalty. Any other non-OEM limited slip differential
allowed with +50 lbs. weight penalty. Front spoiler permitted (NF51-V4-900F)."

Applies to Mazda MX-5 on this page: Oscar Jackson

T4 ND MX-5 wheel allowance

#37279 from Josh Smith · Rule change · TB 24-12 (2024-12 Fastrack)

unclearT4 Mazda MX-5 Miata/Club (16-18) wheel size changes to 17 x 7.5 inches.

In T4 Spec Lines, Mazda MX-5 Miata/Club (16-18), change Wheel Size as follows:
"17 x 7.5"

Applies to Mazda MX-5 on this page: Oscar Jackson

Applies to Mazda Miata on this page: Kristina Etherington, Kayla Etherington

T4 T4 BOP

#37281 from Touring Committee · Rule change · TB 24-12 (2024-12 Fastrack)

slowerT4 Mazda RX-8 gets 59mm restrictor and 3200 lbs; MX-5 Club drops to 2550 lbs.

In T4 Spec Lines, Mazda RX-8 Base/R3/Sport/ GT (04-12), change as follows:
Required Restrictor: "60mm 59mm"
Weight: "3125 3200"
In T4 Spec Lines, Mazda MX-5 / Club Model (06-15), change weight as follows:
"2600 2550"

Applies to Mazda MX-5 on this page: Oscar Jackson

T4 Allow 7.5

#37286 from Touring Committee · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT4 Mazda MX5 Miata/Club/RF 19-24 wheel size changes to 17 x 7.5.

In T4 Spec Lines, Mazda MX5 Miata/Club/ RF (19-24), change Wheel Size as follows:
"17 x 7.5"

T4 2016-2018 Mazda Miata MX5

#37085 from Nic Piekarski · Rule change · TB 25-01 (2025-01 Fastrack)

fasterT4 2016-2018 Mazda Miata MX-5 minimum weight reduced to 2575 lbs from 2650 lbs.

In T4 Spec Lines, Mazda MX-5 Miata/Club (16-18), change Min Weight as follows:
"2650 2575"
In T4 Spec Lines, Mazda MX5 Miata/Club/ RF (19-24), add to Notes the following:
"Mazda header 0000-06-5410 allowed."

Applies to Mazda MX-5 on this page: Oscar Jackson

Applies to Mazda Miata on this page: Kristina Etherington, Kayla Etherington

HP Request to Reduce Weight of BMW 325i/is E30 (84-91) Spec Line

#37119 from Tim Schreyer · Rule change · TB 25-01 (2025-01 Fastrack)

fasterEP BMW 325i/is E30 (84-91) weight reduced 50–52 lbs across three spec lines to 2150, 2204, 2258.

In EP SPEC LINES, BMW 325i/is (E30) (84-91), change Weight as follows:
"2200 2150
*2255 2204
**2310 2258"

T4 Remove spec lines that have expired

#37269 from Touring Committee · Rule change · TB 24-12 (2024-12 Fastrack)

neutralT2, T3, T4 remove nine, nine, and thirty-six expired spec lines respectively, effective 2025-01-01.

In T2, Effective 1/1/2025, delete for following Spec Lines in their entirety:
"Acura TL SHAWD (10-13)
Audi S4 (12-14)
Audi S5 (13-14)
Audi TT RS (2018-)
Cadillac ATS-V (16-17)
Cadillac CTS-V (06-07)
Chevrolet Camaro SS (98-02)

Show 49 more lines

Honda Civic Type-R (2017-)
Saturn Sky / Convertible (07-09)"
In T3, Effective 1/1/2025, delete for following Spec Lines in their entirety:
"Audi TTS Coupe (10-11)
Cadillac ATS (2015)
Chevrolet Cobalt (05-07)
Dodge SRT-4 (03-05)
Ford Fiesta ST (2014-)
Hyundai Genesis Coupe (2010-)
Hyundai Veloster Turbo (18-21)
Mini Cooper S (2016-)
Toyota Camry (11-15)"
In T4, Effective 1/1/2025, delete for following Spec Lines in their entirety:
"Acura Integra GS-R VTEC (3 or 4 door) (94-01)
Audi A4 V-6 (96-01) / Volkswagen Passat 2.8 V6 (96-05)
Chevrolet Cobalt SS, Sport Coupe (06-10)
Chevrolet Sonic RS (2011-)
Chrysler/Dodge Neon ACR SOHC (4 door) (01-02)
Dodge Dart (14-15)
Dodge/Plymouth Neon ACR SOHC/DOHC (2/4 door) (95-99)
Fiat 500 Abarth (12-14)
Ford Focus SVT (02.5-04)
Ford Focus ZX4 ST (05-06)
Ford Focus (08-11)
Ford Mustang V-6 (01-04)
Honda Accord LX & EX (03-07)
Honda Accord LX-S/EX/EX-L (08-12)
Honda Civic Coupe Si (99-00)
Honda Civic SI (02-03)
Hyundai Elantra GLS (11-12)
Hyundai Tiburon V-6 (03-08)
Hyundai Veloster Turbo/ R-Spec (14-15)
Kia Forte Koup and Sedan LX/EX (10-13)
Kia Forte Koup and Sedan SX (10-13
Kia Forte Koup (14-15)
Mazda Protégé ES (2000)
Mazda Protégé 5 (02-03)
Mazda6 s (03-07)
Mitsubishi Eclipse GT (00-05)
Nissan Sentra SER (02-03)
Pontiac Firebird V-6 (96-02)
Scion tC (03-07)
Subaru Impreza (non-turbo) (04-06)
Toyota Celica GT (00-05)
Toyota Celica GTS/GT (00-05)
Volkswagen Golf TDI (2010)
Volkswagen Passat (12-14)
Volkswgen Passat TDI (12-14)
Volkswgen Passat 1.8T (2014-)"

HP Request to Update 1988-1991 Civic to Match 1988-1991 CRX

#37444 from ENRIK BENAZIC · Rule change · TB 25-01 (2025-01 Fastrack)

fasterHP Honda Civic 1.5 88-91 weight reduced to 2175 lbs base, 2229 lbs with one asterisk, 2284 lbs with two asterisks.

In HP SPEC LINES, Honda Civic 1.5 (88-91), change Weight as follows:
"2245 2175
*2301 2229
**2357 2284"

T1 T1 Parity Compared to GT4

#37170 from Tony Ave · Rule change · TB 25-02 (2025-02 Fastrack)

slowerT1 Mustang gains 125 lbs to 3600, restrictor shrinks 65mm to 60mm. Corvette gains 50 lbs to 3500, restrictor shrinks 70mm to 67mm. BMW deleted.

In T1 Spec Lines, change Weight and Restrictor Required as follows:
Mustang - Spec Line 1430
Weight: "3475 3600"
Restrictor Required: "65mm 60mm - FPR"
Corvette Spec Line 1190
Weight: "3450 3500"
Restrictor Required: "70mm 67mm - Flat Plate"
In T1 Spec Lines, delete Spec Line BMW # 1190 in its entirety.

T1 Clarification of Request Approval #37273

#37399 from Mark Pfeffer · Rule change · TB 25-02 (2025-02 Fastrack)

unclearT1 E46 M3 Spec Line 1050 allows VAC Motorsports throttle body VAC-TB-S54 on 3.250L engine instead of Dinan.

In T1 Spec Lines, E46 M3 Spec Line # 1050, change Engine Notes as follows:
"Dinan Throttle Body #D760-3400 VAC Motorsports #VAC-TB-S54 allowed on the 3.250L."

T1 C8 Corvette Facts

#37400 from Garry Crook · Rule change · TB 25-02 (2025-02 Fastrack)

fasterT1 Chevrolet Corvette C8 (2023-23) minimum weight reduced from 3600 lbs to 3500 lbs.

In T1 Spec Lines, Chevrolet Corvette C8 (20- 23) - Includes Z51, Spec Line # 1210, change Min. Weight as follows:
"3600 3500"

T1 Camaro Gen 5 Competitive Disadvantage

#37440 from Clark Nunes · Rule change · TB 25-02 (2025-02 Fastrack)

fasterT1 Chevrolet Camaro Gen 5 restrictor increases from 75mm to 80mm flat plate.

In T1 Spec Lines, Chevrolet Camaro Gen 5 (10-15) Including SS, Z28 Spec Line 1135, change Required Restrictor as follows:
"75mm 80mm - Flat Plate"

T1 Tire Changes in the Rules for GT4

#37497 from Joe Rainey · Rule change · TB 25-02 (2025-02 Fastrack)

unclearT1 Audi R8 GT4 Spec Line #4020 maximum tyre size changes to 315 DOT, 305/645, or 30/65-18 (f), 33/68-18 (r) Non-DOT.

In T1-GT4 Spec Lines, Audi R8 GT4 Spec Line #4020, change Max Tire Size as follows:
"315 DOT, 305/645, or 30/65-18 (f), 33/68-18 (r) Non-DOT"

T4 Ford Mustang V6 (05-14)

#37516 from Touring Committee · Rule change · TB 25-02 (2025-02 Fastrack)

neutralT4 Ford Mustang V6 (05-14) final drive set to 3.45, GT/CS front bumper cover permitted with front fascia.

In T4 Spec Lines, Ford Mustang V6 (05-14), change as follows:
Final drive: "3.45"
Notes: "GT/CS front bumper cover #AR3Z-17D957-BA, allowed if used with front fascia."

T4 Request to Classify Club Spec in Appropriate Touring Classes

#37523 from Andrew Benagh · Rule change · TB 25-02 (2025-02 Fastrack)

neutralFord SCCA Club Spec Mustang classified T3 at 3350 lbs with driver; Mazda SCCA Club Spec MX-5 classified T4 at 2500 lbs with driver.

In T3 Spec Lines, classify Ford SCCA Club Spec Mustang (CSM) as follows:

A specification table follows in the original; it is not shown here.

Applies to Mazda MX-5 on this page: Oscar Jackson

HP Effective date for Jan 2025 GCR updates

#37654 from Doug Piner · Rule change · TB 25-02 (2025-02 Fastrack)

slowerEP BMW Z3 2.5L requires 52mm flat plate intake restrictor; Z3 2.8L 55mm; 328i/is E36 58mm; 328i/ci E46 58mm; 325i/is E46 56mm; 325i/is E36 56mm; 325is M-Technic 56mm.

In EP Spec Lines, add to Notes as follows:
BMW Z3 2.5LL "(Effective 2/21/2025) 52mm Flat Plate Intake Restrictor is required."
BMW Z3 2.8L (97-00): "(Effective 2/21/2025) 55mm Flat Plate Intake Restrictor is required."
BMW 328i/is E36 (96-99): "(Effective 2/21/2025) 58mm Flat Plate Intake Restrictor is required."
BMW 328i/ci E46 (01-06): "(Effective 2/21/2025) 58mm Flat Plate Intake Restrictor is required."
BMW 325i/is E46 (01-06): "(Effective 2/21/2025) 56mm Flat Plate Intake Restrictor is required."
BMW 325i/is E-36 (92-95): "(Effective 2/21/2025) 56mm Flat Plate Intake Restrictor is required."
BMW 325is M-Technic (1994): "(Effective 2/21/2025) 56mm Flat Plate Intake Restrictor is required."

Cal Club 2025 → Cal Club 2026 2025-02-22 to 2026-02-21

HP Request Competition Adjustment to BMW Z3 2.5L

#37120 from Tim Schreyer · Rule change · TB 25-01 (2025-01 Fastrack)

slowerEP BMW Z3 and 3-series models get smaller intake restrictors: Z3 2.5L to 52mm, Z3 2.8L to 55mm, 328i to 58mm, 325i to 56mm.

In EP Spec Lines, change Notes as follows:
BMW Z3 2.5LL "(Effective 3/1/2025) 56mm 52mm Flat Plate Intake Restrictor is required."
BMW Z3 2.8L (97-00): "(Effective 3/1/2025) 59mm 55mm Flat Plate Intake Restrictor is required."
BMW 328i/is E36 (96-99): "(Effective 3/1/2025) 62mm 58mm Flat Plate Intake Restrictor is required."
BMW 328i/ci E46 (01-06): "(Effective 3/1/2025) 62mm 58mm Flat Plate Intake Restrictor is required."
BMW 325i/is E46 (01-06): "(Effective 3/1/2025) 60mm 56mm Flat Plate Intake Restrictor is required."
BMW 325i/is E-36 (92-95): "(Effective 3/1/2025) 60mm 56mm Flat Plate Intake Restrictor is required."
BMW 325is M-Technic (1994): "(Effective 3/1/2025) 60mm 56mm Flat Plate Intake Restrictor is required."

HP Interpretation of Production Rules on Mirrors

#37235 from Lawrence Slivinski · Rule change · TB 25-03 (2025-03 Fastrack)

neutralEP, FP, HP: interior or exterior mirrors meeting rule 9.3.36 now permitted.

In GCR, add new rule as Section 9.1.5.E.10.f:
"Any interior or exterior mirror(s) that meets rule 9.3.36 may be used."

HP HP Class Adjustments

#37459 from Production Committee · Rule change · TB 25-01 (2025-01 Fastrack)

slowerHP Mazda 2 11-14 base weight up 50 lbs to 2045; all VW 80s models up 50 lbs to 2150 base.

In HP SPEC LINES, change Weight as follows:
Mazda 2 (11-14)
"(Effective 3/1/2025) 1995 2045
*2045 2096
**2095 2147"
Volkswagen Golf (GTI, GT, GL) (85-92)
"(Effective 3/1/2025) 2100 2150
*2153 2204

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**2205 2258"
Volkswagen Jetta (GLI, GL) (85-92)
"(Effective 3/1/2025) 2100 2150
*2153 2204
**2205 2258"
Volkswagen Rabbit 1780
"(Effective 3/1/2025) 2100 2150
*2153 2204
**2205 2258"
Volkswagen Scirocco 1780 (8-valve) (83-88)
"(Effective 3/1/2025) 2100 2150
*2153 2204
**2205 2258"

HP Weight Reduction for Honda S2000

#37466 from Michael Unger · Rule change · TB 25-03 (2025-03 Fastrack)

fasterEP Honda S2000 1997cc base loses 75 lbs to 2375; 2157cc base loses 60 lbs to 2450.

In EP, Spec Lines make the following weight changes:

A specification table follows in the original; it is not shown here.

HP Mazda 1999 Miata 1.8L

#37488 from Joe Carr · Rule change · TB 25-03 (2025-03 Fastrack)

fasterEP Mazda MX-5/Miata 99-05 minimum weight drops to 2100 lbs, 2153 lbs with power adder, 2205 lbs with two adders.

In EP Spec Lines, make the following weight change:
Mazda MX-5 /Miata (99-05):
"2150 2100
*2204 2153
**2258 2205"

HP MINI Cooper (07-13) Spec Line Correction: Errors and Omissions

#37560 from Robert Bax · Rule change · TB 25-03 (2025-03 Fastrack)

slowerHP Mini Cooper 07-13 engine corrected to DOHC; valve lift limit reduced to 0.390 inches.

In HP Spec Lines, Mini Cooper (07-13) (includes 09-15 convertible and 12-15 Coupe), change as follows:
Engine Type:
"4 Cyl
SOHC DOHC"
Notes:
"Compression ratio limited to 11.0:1, Valve lift limited to .450”.390"."

Applies to Mini Cooper on this page: Tom Tuttle

T1 Correct and make new T1 BOP adjustments.

#37737 from Touring Committee · Rule change · TB 25-03 (2025-03 Fastrack)

unclearT1 Mustang Spec 1430 restrictor opens 60mm to 65mm; Spec 1460 weight rises to 3500 lbs, restrictor 70mm; Corvette 1190 restrictor opens 67mm to 70mm; BMW 1090 restrictor narrows 40mm to 35mm; BMW 1100 weight rises to 3350 lbs.

In T1 Spec Lines, change Weight, Restrictor Required and/or Notes as follows:
Mustang - Spec Line 1430:
Restrictor Required: "60mm 65mm - FPR"
Mustang - Spec Line 1460:
Weight: "3425 3500"
Restrictor Required: "70mm - FPR"
Corvette Spec Line 1190:
Restrictor Required: "67mm 70mm - Flat Plate"

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BMW - Spec Line 1090:
Required Restrictor: "(2) X 40mm 35mm diameter hole inlet restrictor plate required"
Chassis Notes: "This spec line is set to expire 12/31/25."
BMW - Spec Line 1100:
Minimum Weight: "3150 3350”

HP Request for Classification of Chevrolet Spark

#37755 from Kristian Smith · Rule change · TB 25-04 (2025-04 Fastrack)

neutralChevrolet Spark 16-22 classified HP Pre at 1850 lbs minimum weight, fuel injected, 1399 cc.

In HP Spec Lines, classify the Chevrolet Spark (16-22):

A specification table follows in the original; it is not shown here.

HP Request to Lower Ford Festiva Minimum Weight to 1600 LBS

#37939 from Doug DeRonne · Rule change · TB 25-04 (2025-04 Fastrack)

fasterHP Ford Festiva 88-93 minimum weight drops to 1600 lbs, variants to 1640 and 1680 lbs; compression ratio raised to 11.0:1.

In HP Spec Lines "Ford Festiva (88-93)" change as follows:
Weight:
"1700 1600
*1743 1640
**1785 1680"
Notes:
"Compression ratio limited to 10.5 11.0:1. Valve lift limited to .450”."

T1 Cadillac CT4-V Blackwing

#38003 from Touring Committee · Rule change · TB 25-04 (2025-04 Fastrack)

neutralCadillac CT4-V Blackwing added to T1 Spec Line 1115, 3564cc, 3750 lbs minimum weight.

In T1 Spec Lines, classify Cadillac CT4-V Blackwing as follows:

A specification table follows in the original; it is not shown here.

T1 Acceptance of Porsche 981 GT4 Clubsport into T1

#36664 from John Brown · Rule change · TB 25-05 (2025-05 Fastrack)

neutralPorsche 981 GT4 Clubsport added to T1 as spec line 4085, minimum weight 3100 lbs with driver.

In T1-GT4 Spec Lines, classify Porsche 981 GT4 Clubsport as follows:

A specification table follows in the original; it is not shown here.

T1 Request to Restore T1 Honda S2000 to Proper Weights

#37644 from David Mead · Rule change · TB 25-05 (2025-05 Fastrack)

fasterT1 Honda S2000 minimum weight reduced from 2950 lbs to 2900 lbs.

In T1 Spec Lines, Honda S2000, Spec Line 1530, change as follows:
Minimum Weight: "2950 2900"
Chassis Notes: "This spec line is set to expire as of 12/31/2025 if not represented in Majors competition in 2025."

T1 DCT Transmission in E46

#37964 from Matt Spicuzzi · Rule change · TB 25-05 (2025-05 Fastrack)

neutralT1 BMW E46 M3 permits BMW #GS7D36SG aftermarket sequential transmission in SL# 1060 and 1070.

In T1 Spec Lines, BMW E46 M3, add to Chassis Notes the following:
SL# 1060: "BMW #GS7D36SG transmission permitted as an aftermarket sequential option."
SL# 1070: "BMW #GS7D36SG transmission permitted as an aftermarket sequential option."

Applies to BMW M3 on this page: Ian Barberi

SM Clarify Tire Marking Regs

#38005 from Greg Amy · Rule change · TB 25-05 (2025-05 Fastrack)

neutralSM cars limited to one set of Hoosier SM 7.5 P205/50/ZR17 per Super Tour event weekend for dry sessions.

In GCR Section 9.1.7.C.1.6.c., change as follows:
"1. A mandatory impound for all SMX competitors will occur after the first dry qualifying or race session. All tires will be marked
for the remainder of the race weekend. It is the competitor’s responsibility to report to impound and ensure their tires are
marked prior to leaving impound. SM cars are limited to one set of Hoosier SM 7.5 P205/50/ZR17 per Hoosier Super Tour event
weekend for all dry qualifying and race sessions. This limitation does not include testing or practice sessions. Approved rain tires
will not be required to be marked.
2. A mandatory impound for all SM competitors is required after the first dry qualifying or race (if rain in qualifying) session. It is
the competitor’sresponsibility to ensure their tires are marked prior to going on track for the next session. A mandatory impound

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for all SM competitors will occur after the first dry qualifying or race session. All tires will be marked for the remainder of the
race weekend. It is the competitor’s responsibility to report to impound and ensure their tires are marked prior to leaving
impound.
3. If a competitor damages a tire or wheel, and there is a safety concern, the competitor must find the Hoosier Super Tour Series
Tech Chief or SM CCC, if assigned, for inspection. At the direction of the Hoosier Super Tour Series Tech Chief or SM CCC, the
competitor will be allowed to substitute alternate used tire(s) to replace the damaged tire(s). New tires are not an option as a
replacement tire for a damaged tire If a competitor damages a tire or wheel and there is a safety concern, the competitor must
find the Hooseir Super Tour Series Tech Chief or SMX CCC, if assigned, for inspection. At the discretion of the Hoosier Super
Tour Series Tech Chief of SMX CCC the competitor may be allowed to substitute alternate used tires(s) to replace the damaged
tire(s). New tires are not an option as a replacement tire for a damaged tire."

T4 Correct Ring and Pinion Ratio to T3, Sorry I Mean T4 3.7 V6 Stang

#38041 from David Mead · Rule change · TB 25-05 (2025-05 Fastrack)

neutralT4 Ford Mustang V6 05-14 allows GT 8.8 rear axle or 7.5 axle with 3.45:1 ratio.

In T4 Spec Lines, Ford Mustang V6 (05-14), add to Notes the following:
"GT 8.8 rear axle assembly allowed. 3.45 or 3.55 final drive ratio allowed. 7.5 rear axle assembly with 3.45:1 final drive allowed."

T4 T4 Mustang

#38058 from Scotty B White · Rule change · TB 25-05 (2025-05 Fastrack)

neutralT4 Ford Mustang V6 05-14 now permits OEM style rear deck spoiler similar to Laguna/CS packages.

In T4 Spec Lines, Ford Mustang V6 (05-14), add to Notes as follows:
"OEM style rear deck spoiler similar to Laguna/CS packages permitted.”

T1 Reduce E92 M3 Minimum Weight to 3050

#38092 from Shane Brown · Rule change · TB 25-05 (2025-05 Fastrack)

fasterT1 BMW M3 E92 minimum weight reduced to 3300 lbs.

In T1 Spec Lines, BMW M3 E92 (08-13), Spec Line 1100, change Min. Weight as follows:
"3350 3300"

T1 Finalize Spec Line for T1 Darkhorse

#38106 from Touring Committee · Rule change · TB 25-05 (2025-05 Fastrack)

fasterT1 Mustang Darkhorse R gets 315 front and rear tyres, loses 500 lbs minimum weight to 3600.

In T1 Spec Lines, Mustang Darkhorse R (Mustang Challenge) Spec Line- 4119, change as follows:
Tire size: "305 315 (f) 315(r)"
Performance Control: "TBD"
Min. Weight with driver (LBS): "10.5 (f) 11 (r) 3600"
Chassis Notes: "Must conform to Mustang Challenge Rules. Tires conforming to Mustang Challenge rules are permitted. **This
car is not eligible for the Runoffs until it has competed in 3 Super Tour events.**"

T4 T4 Mustang

#38059 from Scotty B White · Rule change · TB 25-06 (2025-06 Fastrack)

fasterT4 Ford Mustang V6 05-14 weight drops from 3400 to 3300 lbs.

In T4 Spec Lines, Ford Mustang V6 (05-14), change as follows:
Final Drive: "3.45 or 3.31"
"Weight: "3400 3300"

T4 SSC tire allowance

#38216 from Benjamin Bunk · Rule change · TB 25-06 (2025-06 Fastrack)

neutralT4 Scion FR-S and Subaru BRZ Solo Spec allow any 200TW 225/45/17 or 215/45/17 DOT tire.

In T4 Spec Lines, Scion FR-S Solo Spec Coupe (13-16), change Notes as follows:
"Any 200TW 225/45/17 or 215/45/17 DOT tire permitted."
In T4 Spec Lines, Subaru BRZ Solo® Spec Coupe (13-16), change Notes as follows:
"Any 200TW 225/45/17 or 215/45/17 DOT tire permitted."

Applies to Scion FR-S on this page: Tony Kiratsous

SM SMX Data Submission - Penalties

#38248 from Kathy Barnes · Rule change · TB 25-06 (2025-06 Fastrack)

neutralSMX drivers must submit data acquisition files on time or face suspension and $250 fine.

In GCR, Section 9.1.7.1.23 add new level 5 infraction as follows:
Level: "5"
Infraction: "Failure to successfully submit (received by data@specmx-5.com) data acquisition file to data@specmx-5 per the
timeframes outlined in GCR section 9.1.7.1.20."
Penalty: "May suspend the driver (i.e. suspend) of the Spec MX-5 that failed to submit data on time or at all from competing in
SCCA events for the 3 months following the suspension.
A level 5 infraction may carry a $250.00 fine."

HP Base Weight Adjustment for H-Production X1/9 Spec Lines

#38255 from Matthew Brannon · Rule change · TB 25-06 (2025-06 Fastrack)

fasterHP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines.

In HP Spec Lines, change Weight as follows:
Fiat X-1/9 & Bertone1500: “1790 1740 *1835 1784 **1880 1827”
Fiat X-1/9 1300: “1650 1600 *1691 1640 **1733 1680”
Fiat X-1/9 1300: “2060 2010”
Fiat X-1/9 1500: “1950 1900”

SM Committee) SMX Penaly Clarification updated language

#38337 from Spec Mazda (SM/SMX · Rule change · TB 25-06 (2025-06 Fastrack)

neutralSMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fine; level 2 and 4 may carry $500 fine.

In GCR, Section 9.1.7.1.23. change as follows:
Rename as follows: "Penalties Clarification – Non-Compliant Parts SMX Penalty Guidelines"
Change the Penalty language for level 1 to the following: "A level 1 infraction carries may carry a $1,000 fine."
Change the penalty language for level 2 to the following: "A level 2 infraction carries may carry a $500 fine."
Change the penalty language for level 3 to the following: "A level 3 infraction carries may carry a $1,000 fine."
Change the penalty language for level 4 to the following: "A level 4 infraction carries may carry a $500 fine."

T4 Allow B-Spec cars to run in T4

#38439 from Derrick Ambrose · Rule change · TB 25-07 (2025-07 Fastrack)

neutralT4 now permits B-Spec and C-Spec cars to compete in the class.

In GCR, Section 9.1.9.2, Touring car eligibility, change as follows:
"Touring car eligibility: Cars are eligible for the class they are listed with a specification line and with the specific allowances
permitted. In addition T2-T4 cars may race one class up in touring classes above their specification line class as long as they are a
legal T2-T4 car and conform to their specification line allowances as classified. Cars conforming to B-Spec or C-Spec rules are
permitted to compete in Touring 4."

HP BMW Z4 update

#38490 from Bryce McGuire · Rule change · TB 25-07 (2025-07 Fastrack)

slowerEP BMW Z4 03-05 restricted to 52mm flat plate intake restrictor.

In EP Spec Lines, BMW Z4 (03-05), add to Notes the following:
“52mm Flat Plate Intake Restrictor.”

HP EP Fiat 124 Spider Competition Adjustment Request

#38498 from John Baucom · Rule change · TB 25-07 (2025-07 Fastrack)

fasterEP Fiat 124 Spider 1600 & 2000 weight drops 50 lbs to 2000; carburetors gain 2mm chokes to 36mm.

In EP Spec Lines, Fiat 124 Sport Spider 1600 & 124 Spider 2000, change as follows:
Weight: "2050 2000"
Carburetor No. & Type: "(2) Weber 40 IDF-40IFI, (2) Solex C40P116, 34 36mm choke(s) req’d, (2) Weber 45DCOE w/ 34 36 mm
choke(s) on I.R. manifold or fuel injection."

T4 Incorrect Touring Heading

#38451 from Terry Hanushek · Rule change · TB 25-08 (2025-08 Fastrack)

neutralT2, T3, T4 Spec Lines table header changed from T2 to ET.

In T2-T4 Spec Lines, change Table Header as follows:
"T2 ET"

HP HP Plymouth Arrow spec omission

#38995 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

neutralHP Plymouth Arrow transmission max speeds clarified to 4 or 5.

In HP Spec Lines, Plymouth Arrow (76-80), add the following wording to Trans. Speeds(max):
"4 or 5"

HP Add Wheel Diameter to Appendix G

#39008 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

neutralEP, FP, HP wheel diameter added to Appendix G as absolute maximum specification.

In Appendix G.2.3, change as follows:
"Rim width and diameter are is absolute maximums."

HP Add TB ID tolerance to general Prod rules

#39009 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

neutralEP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only.

In GCR, Section 9.1.5.E., change as follows:
9.1.5.E.1.b.4: "The inside dimensions of the throttle body casting/housing (as measured at the throttle butterfly) must remain
stock (tolerance of +/-.25mm), but the throttle body can otherwise be ported and polished."
9.1.5.E.2.b.4: "The inside dimensions of the throttle body casting/housing and all dimensions of the throttle butterfly must
remain stock (tolerance of +/-.25mm)."

HP Please Lower Weight of 280Z

#38871 from Matthew Miller · Rule change · TB 25-09 (2025-09 Fastrack)

fasterEP Nissan 280Z minimum weight reduced from 2560 to 2400 lbs.

In EP Spec Lines, Nissan 280Z, change Weight (lbs) as follows:
"(Effective 11/1/2025) 2560 2400
*2624 2460
**2688 2520"

HP Miata Weight Adjustment Follow Up

#38949 from Don Tucker · Rule change · TB 25-10 (2025-10 Fastrack)

fasterEP Mazda MX-5 1.8L 90-97 weight reduced to 2125 lbs from 2150 lbs.

In EP Spec Lines, Mazda MX-5 / Miata 1.8L (90-97), Effective 11/1/2025 make the following weight change:
"2150 2125"

T4 02-06 Mini Cooper Gear Ratios

#38966 from Trenton Kramer · Rule change · TB 25-11 (2025-11 Fastrack)

unclearT4 Mini Cooper S R53 02-06 gear ratios changed to 12.79, 7.79, 5.65, 4.62, 3.83, 3.13 or 11.42, 7.18, 5.39, 4.40, 3.65, 2.96.

In T4 Spec Lines, Mini Cooper S R53 (02-06), change Gear Ratios as follows:
"12.79, 7.79, 5.65, 4.62, 3.83, 3.13 or overall- 11.42, 7.18, 5.39, 4.40, 3.65, 2.96"

HP Weight Break for 1098 Midget / Sprite

#38970 from Kendall Jones · Rule change · TB 25-10 (2025-10 Fastrack)

fasterHP Austin-Healey Sprite/Midget 1098cc minimum weight drops 80 lbs to 1550.

In HP Spec Lines, Austin-Healey Sprite/Midget 1098cc, Effective 11/1/2025make the following weight change:
"1630 1550"

T4 Reinstatement of the 2005-2010 Cobalt into T4

#38987 from Tim Little · Rule change · TB 25-11 (2025-11 Fastrack)

neutralChevrolet Cobalt SS Sport Coupe 06-10 reinstated to T4 with 2384cc engine, 2628 restrictor, 2700 lbs minimum weight.

In T4 Spec Lines, classify Chevrolet Cobalt SS, Sport Coupe (06-10) as follows:

A specification table follows in the original; it is not shown here.

HP HP Volvo 142 spec omission

#38994 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

slowerHP Volvo 142/142E gains compression ratio limit 12.0:1 and valve lift limit .425".

In HP Spec Lines, Volvo 142/142E P-1800 Engine, Effective 11/1/2025 add the following wording to Notes:
"Comp. Ratio limited to 12.0:1. Valve lift limited to .425”."

HP HP Mini DOHC 1.6

#38996 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

slowerHP Mini Cooper 07-15 valve lift reduced to .390", from .450".

In HP Spec Lines, Mini Cooper (07-13) (includes 09-15 convertible and 12-15 Coupe), Effective 11/1/2025 make the following
changes to the Notes:
"Compression ratio limited to 11.0:1, Valve lift limited to .450”.390"."

HP Add to Rabbit description

#39019 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

neutralFP and HP Volkswagen Rabbit descriptions updated: Convertible changed to Cabriolet in FP; Cabriolet added to three HP engine variants.

In FP Spec Lines, make the following spec line correction:
"Volkswagen Rabbit (Includes Convertible Cabriolet)"
In HP Spec Lines, make the following spec line correction:
"Volkswagen Rabbit 1588 (Includes Cabriolet)"
"Volkswagen Rabbit 1715 (Includes Cabriolet)"
"Volkswagen Rabbit 1780 (Includes Cabriolet)"

HP Clean-up 9.1.5.E.7e

#39025 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

neutralEP, FP, HP: rear drum brake to disc conversion clarified; rotors solid, diameter limited to largest front rotor permitted.

In GCR, Section 9.1.5.E.7., change as follows:
"e. Cars fitted with rear drum brakes, can convert to rear disc brakes without penalty. Note that the “Brakes Std.” and “Brakes
Alt.” listings on a vehicle’s spec line do not prohibit a car that was fitted with rear drum brakes stock, from converting to rear
disc brakes under this rule. When converting from rear drum brakes to rear disc brakes:
1. Rear brake rotors must be solid and can be no larger in diameter than the largest permitted front brake rotor, as defined on
the vehicle’s spec line.
2. Rear calipers and mounting brackets are unrestricted but must be made of a ferrous or aluminum material. The standard and
alternate brake listings on a vehicle’s specification line, does not prohibit a car that was fitted with rear drum brakes as stock

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from converting to rear disc brakes under this rule.
3. The “Brakes Std.” and “Brakes Alt.” listings on a vehicle’s spec line do not prohibit a car that was fitted with rear drum brakes
as stock from converting to rear disc brakes under this rule."

T4 Request to Classify Mercedes C230K

#39080 from Patrick Morgan · Rule change · TB 25-11 (2025-11 Fastrack)

neutralMercedes C230 Kompressor 2002-2005 classified in T4 at 3240 lbs with 17-inch wheels and 300/290 mm brakes.

In T4 Spec Lines, classify Mercedes C230 Kompressor (2002-2005) as follows:

A specification table follows in the original; it is not shown here.

HP Add TB size to Ford Mustang (94-98) Spec Line

#39130 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

neutralEP Ford Mustang (94-98) fuel injected throttle body inside diameter specified at 60.

In EP Spec Lines, Ford Mustang (94-98) add the following to the Fuel Injected Equipped Throttle Body Inside Diameter column:
"60"

T4 ND Gearset Request for T4

#39166 from Josh Smith · Rule change · TB 25-11 (2025-11 Fastrack)

neutralT3 and T4 Mazda MX-5 Miata models add approved gear kit PT#-0000-02-6100 to notes.

In T4 Spec Lines, Mazda MX5 Miata/Club/ RF (19-24), add to Notes the following:
"Gear kit Kit PT#- 0000-02-6100."
In T4 Spec Lines, Mazda MX-5 Miata/Club (16-18), add to Notes the following:
"Gear kit Kit PT#- 0000-02-6100."
In T3 Spec Lines, Mazda MX-5 Miata (16-18), add to Notes the following:
"Gear kit Kit PT#- 0000-02-6100."
In T3 Spec Lines, Mazda MX-5 Global Cup Miata (2016-2021) ND1, ND, add to Notes the following:
"Gear kit Kit PT#- 0000-02-6100."

Applies to Mazda MX-5 on this page: Oscar Jackson

Applies to Mazda Miata on this page: Kristina Etherington, Kayla Etherington

T4 E&O wheel size on ND

#39168 from Josh Smith · Rule change · TB 25-11 (2025-11 Fastrack)

unclearT4 Mazda MX-5 Miata/Club 16-18 wheel size changed to 17 x 7.5 inches.

In T4 Spec Lines, Mazda MX-5 Miata/Club (16-18), change Wheel Size (in.) as follows:
"17 x 7.5"

Applies to Mazda MX-5 on this page: Oscar Jackson

Applies to Mazda Miata on this page: Kristina Etherington, Kayla Etherington

T4 ND Spec Lines Wrong PT#'s

#39170 from Josh Smith · Rule change · TB 25-11 (2025-11 Fastrack)

neutralT4 Mazda MX-5 Miata/Club/RF (19-24) and (16-18) remove discontinued hardtop part #0000-07-5901; T3 MX-5 Miata (16-18) and Global Cup ND (16-21) same.

In T4 Spec Lines, Mazda MX5 Miata/Club/ RF (19-24), change Notes as follows:
"Factory bolt-in roll bar/ cross member may be removed to facilitate roll cage installation. The following item(s) must remain
stock: transmission differential unless specified below. Retractable hardtop option permitted but must be disabled from moving
action and positively fastened. Any OEM or aftermarket hardtop is permitted that retains the OEM roof silhouette, including
Mazda hardtop part #0000-07-5902-ND and part #0000-07-5901 (discontinued DG Motorsports). 29mm (f) 16mm (r) sway bars
allowed. 3rd and 4th gear may be replaced with the following parts- (0000-02-5803-02, 0000-02-5803-01, 0000-02-5804-02,
0000-02-5804-01). Suspension package permitted with a 100 lbs. weight increase that includes the following parts: front springs
#0000-04-9700-08, springs up to 500lb front and 300lb rear allowed. Mazda tower brace 0000-04-5626 allowed. Mazda header

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0000-06-5410 allowed."
In T4 Spec Lines, Mazda MX-5 Miata/Club (16-18), change Notes as follows:
"Factory bolt-in roll bar/ cross member may be removed to facilitate roll cage installation. Retractable hardtop option permitted
but must be disabled from moving action and positively fastened. Any OEM or aftermarket hardtop is permitted that retains the
OEM roof silhouette, including Mazda hardtop part #0000-07-5902-ND and part #0000-07-5901 (discontinued DG Motorsports).
29mm (f) 16mm (r) sway bars allowed. Up to 500lb front and 300lb rear springs allowed. Mazda Motorsports Header part
#0000-06-5410 allowed. Mazda tower brace 0000-04-5626 allowed. 3rd and 4th gear may be replaced with the following parts-
(0000-02-5803-02, 0000-02-5803-01, 0000-02-5804-02, 0000-02-5."
In T3 Spec Lines, Mazda MX-5 Miata (16-18), change Notes as follows:
"Factory bolt-in roll bar/ cross member may be removed to facilitate roll cage installation. Header permitted. Cold air intake
permitted. Front strut brace permitted. Front and rear sway bars permitted up to 35mm, Springs 800 front and 800 Rear max
permitted. Any OEM or aftermarket hardtop permitted that retains the OEM roof silhouette including Mazda hardtop part
#0000-07-5902- ND and part #0000-07-5901 (discontinued DG Motorsports top). If a hardtop is used, latches shall be replaced
with positive fasteners. Retractable hardtop option permitted but must be disabled from moving action and positively fastened.
In T3 Spec Lines, Mazda MX-5 Global Cup Miata (2016-2021) ND1, ND, change Notes as follows:
"Shoulder harness installation must conform to FIA mounting specifications that are approved for this vehicle per section 6.2 FIA
article 253, safety equipment. Must meet all ND2 MX-5 Global Cup rules. Any OEM or aftermarket hardtop is permitted that
retains the OEM roof silhouette, including Mazda hardtop Mazda hardtop part #0000-07-5902-ND and #0000-07-5902-ND part
#0000- 07-5901 (discontinued DG Motorsports). If a hardtop is used, latches shall be replaced with positive fasteners. OBD2
requirement does not apply. Ballast box may be removed. ND2s with sequential gearbox allowed +100 lbs.

Applies to Mazda MX-5 on this page: Oscar Jackson

Applies to Mazda Miata on this page: Kristina Etherington, Kayla Etherington

T4 Touring 4 Post-Runoffs BOP Adjustments and Changes

#39251 from Touring Committee · Rule change · TB 25-11 (2025-11 Fastrack)

In T4 Spec Lines, Acura RSX/ RSX Type-S (02-06), change Restrictor as follows:
"55mm FPR"
In T4 Spec Lines, Acura TSX (2004-2008), change Restrictor as follows:
"47mm FPR 52mm FPR"
In T4 Spec Lines, BMW Z4 2.5L (03-05) , change Weight as follows:
"3050 2950"
In T4 Spec, BMW 320i (14-15), remove this spec line in its entirety.
In T4 Spec Lines, BMW 323 (98-00), change as follows:

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Tire size: "225 245"
Weight: "3250 3150"
In T4 Spec Lines, Ford Mustang V6 (05-14), change as follows:
Restrictor: "50mm 43mm"
Weight: "3300 3400"
In T4 Spec Lines, Honda Civic Si (06-11), change Restrictor as follows:
"55mm"
In T4 Spec Lines, Honda Civic Si (12-15), change as follows:
Restrictor: "47mm 52mm
Notes: "Transmission and Differential must be stock."
In T4 Spec Lines, Mazda MX-5 / Club Model (06-15), change as follows:
Weight: "2550 2500"
Notes: "Factory bolt-in roll bar/cross member may be removed to facilitate roll cage installation. MSR option permitted.
Suspension package permitted with a 100 lbs. weight increase that includes the following parts: front spring mount PT#-0000-
04-5259, front springs #0000-04-9700-08, rear spring mount PT#-0000-04-5258, rear springs #0000- 04-9400-07, helper springs
#0000-04-HLPR-EB (optional), Swaybar kit – PT#-0000-04-5306-EB that includes (front sway bar kit PT#0000-04-5306-FT, rear
sway bar kit PT#-0000-04-5306-RR), offset front camber bushing PT#- 0000-04-5407-NC. Mazda Motorsports cold air intake part
#0000-06-5150-KT allowed. Mazda Motorsport RX8 rear Hub Conversion kit part number 0000-04-5811-KT allowed, RX8 front
hubs PT# F189-33-04X allowed. Allow Mazda header part numbers 0000-06-5407 or 0000-06-5407-NC. Any OEM or aftermarket
hardtop is permitted that retains the OEM roof silhouette, including Mazda hardtop and part #0000-07-5901-CC. Aftermarket
power steering reservoir is allowed. Mazda Transmission kit part # 0000-02-5700. Mazda Motorsports LSD #32655 permitted
without penalty. Any other non-OEM limited slip differential allowed with +50 lbs. weight penalty. Front spoiler permitted
(NF51-V4-900F). Transmission kit # 0000-02-57
In T4 Spec Lines, Pontiac Solstice / Saturn Sky (06-09), change as follows:
Weight: "2800 2700"
Brakes: "(F) 296 315 Vented Disc max (R) 278 Solid Disc"
Notes: "GM calipers #22720705, and #25900764 permitted"
In T4 Spec Lines, Scion FRS/10 series (13-16), change Weight as follows:
"2925 2875"
In T4 Spec Lines, Subaru BRZ/ BRZ Limited (13-16), change Weight as follows:
"2925 2875"
In T4 Spec Lines, Subaru BRZ (17-21), change Weight as follows:
"3000 2950"
In T4 Spec Lines, Toyota 86, GT (17-21), change Weight as follows:
"3000 2950"
SCCA Runoffs

Applies to Mazda MX-5 on this page: Oscar Jackson

HP Request to Re-Classsify Datsun SPL-311 to HP from FP

#39116 from Robert Heatwole · Rule change · TB 25-12 (2025-12 Fastrack)

neutralDatsun SPL-311 newly classified to HP at 2050 lbs with 1595cc OHV iron engine and specified carburetors.

In HP Spec Lines, classify Nissan/Datsun SPL 311 as follows:

A specification table follows in the original; it is not shown here.

HP TR2 Notes E&O

#39180 from Anthony Parker · Rule change · TB 25-12 (2025-12 Fastrack)

unclearEP Triumph TR2-TR4A allows 5-speed gearbox without overdrive; removes Weber carb and weight specification.

In EP Spec Lines, Triumph TR2, 3, 3A, 4, 4A, TR4, TR4A, IRS, make the following change to the Notes:
"Front apron assembly may be made of alternate material. Three (3) Weber 40 DCOE on IR manifold with 28mm chokes @ 1990
lbs. Laycock overdrive, may use 5 speed gearbox without overdrive."

HP Balance of Power

#39187 from Jim Simaras · Rule change · TB 25-12 (2025-12 Fastrack)

slowerEP BMW Z3 2.5L restrictor reduced 52mm to 50mm, weight increased to 2550 lbs base; five other BMW models get smaller restrictors.

In EP Spec Lines, make the following changes to Restrictors:
BMW Z3 2.5L: "52mm 50mm Flat Plate Intake Restrictor"
BMW Z3 2.8L (97-00): "55mm 53mm Flat Plate Intake Restrictor"
BMW 328i/is E36 (96-99): "58mm 55mm Flat Plate Intake Restrictor"
BMW 328i/ci E46 (01-06): "58mm 55mm Flat Plate Intake Restrictor"
BMW 325i/is (E46) (01-06): "56mm 53mm Flat Plate Intake Restrictor"
BMW 325is M-Technic (1994): "56mm 53mm Flat Plate Intake Restrictor"
BMW 325i/is E-36 (92-95): "56mm 53mm Flat Plate Intake Restrictor"

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In EP Spec Lines, BMW Z3 2.5L, change Weight as follows:
"2500 2550
*2563 2614
**2625 2678"

HP Alternative BOP Request for 84-87 Honda CRX/Civic

#39223 from Bill Lamkin · Rule change · TB 25-12 (2025-12 Fastrack)

fasterHP Honda Civic and CRX models get wider 13-inch wheels: 6 to 7 inches.

In HP Spec Lines, change Wheels as follows:
Honda Civic: "13 x 6 7"
Honda Civic DX (92-95): "13 x 6 7"
Honda Civic/Si (84-87): "13 x 6 7"
Honda Civic 1.5 (88-91): "13 x 6 7"
Honda CRX/Si (84-87): "13 x 6 7"
Honda CRX 1.5(88-91): "13 x 67"

T4 Classing 1995-99 Dodge Neon SOHC

#39285 from Preston Obremski · Rule change · TB 25-12 (2025-12 Fastrack)

neutralDodge/Plymouth Neon ACR SOHC/DOHC 95-99 newly classified T4 at 2350 lbs minimum weight.

In T4 Spec Lines, classify Dodge/Plymouth Neon ACR SOHC/DOHC (2/4 door) (95-99) as follows:

A specification table follows in the original; it is not shown here.

T1 Keep S2000 Classification

#39344 from David Mead · Rule change · TB 25-12 (2025-12 Fastrack)

unclearUnable to summarize: letter states intent but provides no actual rule changes to S2000 specification.

In T1 Spec Lines, Honda S2000, change as follows:

T1 Correcting and updating T1 GT4 spec lines

#39394 from Touring Committee · Rule change · TB 25-12 (2025-12 Fastrack)

In T1-GT4 Spec Lines, change as follows:

A specification table follows in the original; it is not shown here.

T1 BOP adjustments to non GT4 T1 cars

#39406 from Touring Committee · Rule change · TB 25-12 (2025-12 Fastrack)

fasterT1 non-GT4 cars: multiple restrictors enlarged (70mm to 73mm, 75mm to 78mm, 55mm to 60mm, 61mm to 70mm); one weight increased to 3600.

In T1 Spec Lines, change as follows:
Spec Line # 1134
Required Restrictor: "61mm 70mm - Flat Plate"
Spec Line # 1140
Required Restrictor: "72mm - Flat Plate"
Spec Line # "1175"
Maximum Displ.: "L76 5967cc OEM"
Minimum Weight: "3250"

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Required Restrictor: "80mm"
Engine Notes: "An L76 is an LS2 block with LS3 intake manifold and heads. All parts must be OEM. May resleeve to stock
parameters for engine repair."
Spec Line # 1180
Required Restrictor: "75mm 78mm - Flat Plate"
Spec Line # 1190
Required Restrictor: "70mm 73mm - Flat Plate"
Spec Line # 1200
Required Restrictor: "72mm 78mm - Flat Plate"
Spec Line # 1201
Required Restrictor: "70mm 73mm - Flat Plate"
Spec Line # 1210
Required Restrictor: "72mm - Flat Plate"
Spec Line # 1350
Required Restrictor: "(2) 55mm 60mm flat plate"
Spec Line # 1370
Required Restrictor: "(2) 55mm 60mm flat plate"
Spec Line # 1390
Required Restrictor: "(2) 55mm 60mm flat plate"
Spec Line # 1420 "*Spec line Expires 12/23"
Required Restrictor: "52mm FPR"
Spec Line # 1429
Required Restrictor: "75mm - FPR"
Spec Line # 1460
Weight: "3500 3600"
Required Restrictor: "70mm - FPR"
Spec Line # 1480
Required Restrictor: "80mm FPR"
Spec Line # 1490
Required Restrictor: "75mm - FPR"
Spec Line # 1590
Engine Notes: "90mm Throttle Body Permitted"
Spec Line # 1595
Required Restrictor: "72mm – FPR"
Spec Line # 1596
Required Restrictor: "61mm 70mm – FPR"
Spec Line # 4120
Required Restrictor: "75mm flat plate"

T1 Remove T1 Spec Line

#39407 from Touring Committee · Rule change · TB 25-12 (2025-12 Fastrack)

neutralT1 BMW M3 E92 (08-13) Spec Line 1090 removed entirely.

In T1 Spec Lines, BMW M3 E92 (08-13) Spec Line number 1090, delete Spec Line in its entirety.

T4 Alternate Placement of Fuse Panel and Electronics Request

#39370 from Aaron Stehly · Rule change · TB 26-01 (2026-01 Fastrack)

neutralT2, T3, T4 cars may relocate under-dash electronics and fuse boxes for access after roll cage installation.

In GCR, Section 9.1.9.2.D.9.d, add the following:
"8. Under-dash electronics including computers, modules and fuse boxes may be relocated so they can be easily accessed after
roll cage installation."

HP E/O: Improve Consistency of the Spec Lines

#39500 from Robert Bax · Rule change · TB 26-01 (2026-01 Fastrack)

unclearHP Toyota MR-2 1.6L (85-89) compression ratio set to 11.0:1.

In HP Spec Line, Toyota MR-2 1.6L (85-89), change Comp. Ratio as follows:
"11.0:1"

T4 Clarify T4 Brake Rotor Allowance

#39503 from David Mead · Rule change · TB 26-01 (2026-01 Fastrack)

neutralT4 Performance now permits 1-piece alternative rotors matching spec line sizes; alternate brake kits allowed same.

In GCR, Section 9.1.9.2.D.6.a.6., change as follows:
"In T2-Performance alternative rotors, including 2 piece rotors are permitted. Rotors must be within 5% of OE diameter or a
maximum diameter of 360mm.
In T3- Performance alternative rotors, including 2 piece rotors are permitted with a maximum diameter of 360mm.
T4- Performance alternative 1-piece rotors are permitted but rotors must meet the sizes listed in the spec line. Spec lines
showing alternate brake kits are also permitted to use 1-piece performance alternative rotors of the same size."

T1 additional T1 adjustment

#39520 from Touring Committee · Rule change · TB 26-01 (2026-01 Fastrack)

unclearT1 Spec Line restrictor changes from 70mm flat plate to unspecified new specification.

In T1 Spec Line, Spec line # 1132, change Restrictor as follows:
"70mm - Flat Plate"

HP Request to Reclassify BMW 2002 Into H Production

#39567 from Jonathan Kinberg · Rule change · TB 26-01 (2026-01 Fastrack)

neutralBMW 2002 newly classified to H Production at 2350 lbs with 1990cc iron block, 40 DCNF carburetor, 11.0:1 compression.

In HP Spec Lines, classify BMW 2002, as follows:

A specification table follows in the original; it is not shown here.

T4 T4 and T3 Feedback

#39230 from Tim Myers · Rule change · TB 26-02 (2026-02 Fastrack)

neutralFord Mustang V6 (05-14) removed from T4 Spec Lines.

In T4 Spec Lines, remove Ford Mustang V6 (05-14) in its entirety.

T4 T4 Mustang 4.0

#39489 from Scotty B White · Rule change · TB 26-02 (2026-02 Fastrack)

fasterT4 Mustang 4.0 V6 tire size increases from 245 to 255.

In T4 Spec Lines, Ford Mustang V6 (05-10), change as follows:
Tire: "245 255"
Notes: "ABS (option code 552) allowed. FR3 Handling Pack #M-2007-FR3V6 allowed (kit does not need to be run in its entirety).
The kit includes: Dampers M-18000-A, Lowering Springs M-5300-N, Sway Bars M- 5490-C, Strut Tower Brace M-20201-F. Ford
Positraction LSD part #M-4204-C75 is allowed. Any springs max F: 500 and R: 400 permitted. Any sway bar up to F: 35mm and R:
28mm permitted. Aftermarket Shocks conforming to T4 rules allowed. Panhard bar, part # BAR-M-4264-A permitted, or any pan
hard bar permitted must be set at same length as a stock bar, center mounting hole to center mounting hole +/- 0.25 inch. An
alternative steel drive shaft is permitted; this drive shaft is otherwise unrestricted, but no modifications to other components

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are permitted to facilitate its installation. An Aluminum driveshaft is allowed. Any LSD permitted. Ford brake kit M-2300-D
allowed. Aftermarket header allowed. GT 8.8 rear axle assembly allowed. 3.45 or 3.55 Alternate final drive ratio allowed. 7.5
rear axle assembly with 3.45:1 final drive allowed. Cold Air Intake allowed. Koni part numbers 8741-1494SPORT (front) and
8241-1240SPORT (rear). Spec clutch #SF661 and flywheel #SF66A permitted. 14” Brembo Brake Kit#M-2300-S permitted."

HP Triumph Spitfire 1296cc Compression Ratio Increase to 12:1

#39589 from Neil Verity · Rule change · TB 26-02 (2026-02 Fastrack)

fasterHP Triumph Spitfire 1296cc compression ratio increases from 11.0 to 12.0:1.

In HP Spec Lines, make the following spec line changes:
Triumph Spitfire:
Carburetion
"Valves: (I) 33.0/(1.30) (E) 29.7/(1.17)
Comp. ratio 11.0 12.0:1, Valve lift .450”
Trans. Speeds: 4"
Triumph Spitfire Mk. III & IV 1500:
Carburetion

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"1300 Valves: (I) 33.0/(1.30) (E) 29.7/(1.17)
1500 Valves: (I) 36.6/(1.44) (E) 29.7/(1.17)
1300: Comp. ratio 12.0:1, Valve lift .450”
1500: Comp. ratio 11.0:1, Valve lift .450”
Trans. Speeds: 4"

T4 Allow Alt Bushing Material in Toe Links

#39607 from David Mead · Rule change · TB 26-02 (2026-02 Fastrack)

fasterT2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously prohibited except in specified examples.

In GCR, Section 9.1.9.D.5.a.1., change as follows:
"T2-T4: A maximum of 3.5 degrees of negative camber is allowed on front and rear suspensions. Spec line part(s) may not be
modified to increase caster and camber. Strut suspensions may adjust camber and caster by the use of eccentric bushings,
eccentric bolts (crash bolts) at the strut-to-spindle, and/or by use of slotted adjustment plates at the top of the strut mounting
plate. If upper strut slotted adjustment plates are used, they shall be located on existing chassis structure, utilizing the
unmodified manufacturer’s original bolt holes and may not serve as reinforcement for that structure. Slotted adjustment plates
(strut camber plates) may incorporate a single spherical bearing (spherical bushing) and a ball thrust bearing per strut tower. On
other forms of suspension, camber and caster adjustment may be achieved by the use of shims and/or eccentric

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bushings. Adjustable toe links with spherical bearings are permitted and may serve no purpose other than adjusting toe
angle. Adjustable toe links are permitted. They are allowed to have performance alternative bushings and spherical bearings.
They may serve no purpose other than adjusting toe angle. Spherical bearings/bushings are not permitted in T2-T4 except for the
specific examples listed in the class rules or vehicle spec line."

T1 LS1 into Corvette C6 Spec Line Request

#39716 from Danny Kellermeyerhttps://crbscca.com/secu · Rule change · TB 26-02 (2026-02 Fastrack)

neutralT1 Corvette C6 LS1/LS6 Spec Line reinstated: 3200 lbs minimum weight, 70mm restrictor required.

In T1 Spec Lines, reinstate Spec Line # 1139, Chevrolet Corvette C6 (05-13) Includes Z51, GrandSport, Z06, Z06 Carbon, as
follows:
Max Displ: "LS1, LS6 OEM"
Min Weight: "3200"
Required Restrictor: "70mm"

What the rules allowed changed as listed; this does not say what any particular car ran.