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BoP Lab / Buttonwillow Raceway Park

STU + GT2 + SM + FF 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; 19, 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
1Mazda 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
2Chevrolet CamaroTim CarrollGT2461:42.698 A-Q11:42.6981:42.698 A-Q11:44.128 A-R11:44.791 A-R1+2.721 A-R1149.0 A-P28.597 A-Q129.839 A-Q144.262 A-Q1
3Chevrolet CamaroJean MeynetGT2281:44.227 A-Q11:44.2271:44.227 A-Q11:46.043 A-R11:46.393 A-R1+1.382 A-R1149.2 A-Q128.543 A-Q130.683 A-Q145.001 A-Q1
4Ford MustangBrad McAllisterGT2291:45.818 B-Q21:45.4091:45.818 B-Q21:46.926 B-R11:47.740 B-R1+1.198 B-R1115.9 B-Q228.729 B-Q230.833 B-R145.847 B-Q2
5Dodge ChallengerBen ValentineGT2124, 241:46.922 A-Q11:46.6081:46.922 A-Q11:47.171 B-R11:47.975 B-R1+0.946 B-R1132.9 A-P29.689 B-Q130.929 A-Q145.990 B-Q2
6Chevrolet CamaroSean BerardiGT291:47.904 A-R21:47.2661:50.095 A-Q21:47.904 A-R21:48.562 A-R2+1.288 A-R2133.2 A-R229.806 A-R231.073 A-R246.387 A-R2
7Porsche GT3Rocky CrockerGT2611:47.914 A-Q11:47.3121:47.914 A-Q11:48.433 A-R11:50.149 A-R1+3.225 A-R1155.7 A-Q129.826 A-Q131.456 A-Q146.030 A-Q1
8SWIFT DB-6 HondaEdward Erlandson 2+ carsFF81:49.259 A-P47.766 A-P
9Chevrolet CorvetteIgor LyustinGT2711:49.904 A-R21:49.6891:50.345 A-Q11:49.904 A-R21:50.694 A-R2+3.172 A-R2145.8 A-Q130.271 A-R231.850 A-R247.568 A-R2
10Mazda RX-3Tony RiveraSTU091:50.913 A-Q21:50.8701:50.913 A-Q21:52.737 A-R21:54.126 A-R2+2.638 A-R2135.2 A-Q230.415 A-Q232.456 A-Q247.999 A-Q2
11Mazda RX-7Guy LaidigGT2521:51.013 A-Q21:50.2661:51.013 A-Q21:52.486 A-R21:53.354 A-R2+1.740 A-R2138.7 A-Q130.134 A-P32.225 A-P47.907 A-Q1
12Piper DL7-HondaEric PoulsenFF481:51.118 B-R11:50.7441:52.044 B-Q11:51.118 B-R11:51.583 B-R1+3.025 B-R1114.7 B-R130.276 B-R131.650 B-R148.818 B-R1
13Mazda 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
14Mazda MiataWhitfield GreggSTU171:51.602 B-P1:51.6022:02.264 B-Q22:01.538 B-R12:02.222 B-R1+1.271 B-R1116.3 A-Q130.652 B-P32.263 B-P48.687 B-P
15BMW M3Wilson PowellSTU771:52.380 B-P1:52.1641:55.401 B-Q11:53.843 B-R11:54.699 B-R1+1.965 B-R1102.6 B-R130.577 B-P32.372 B-P49.215 B-P
16SWIFT DB-Edward Erlandson 2+ carsFF541:53.098 A-Q11:53.0411:53.098 A-Q11:54.741 A-R21:56.774 A-R2+1.819 A-R2133.7 A-Q130.951 A-Q132.299 A-Q149.791 A-Q1
17Mazda 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
18Mazda 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
19Honda S2000Rylan HazeltonSTU491:53.640 B-R11:53.1401:55.834 B-Q11:53.640 B-R11:54.534 A-R2+0.714 A-R2134.8 A-R230.582 B-R132.779 B-R149.779 A-R2
20Swift Db6Johnnie CreanFF351:54.993 A-R21:54.4901:55.247 A-Q21:54.993 A-R21:56.752 A-R2+1.519 A-R2124.5 A-R231.358 A-Q132.841 A-R250.291 A-R2
21BMW 330Sean LovettSTU371:56.492 A-Q21:56.4261:56.492 A-Q21:57.049 A-R21:57.605 A-R2+1.649 A-R2133.7 A-R231.816 A-Q233.669 A-Q150.941 A-Q2
22Mazda RX-7Scott GrahamGT2911:56.607 B-R21:55.0142:00.008 B-Q11:56.607 B-R21:57.173 B-R2+2.205 B-R2100.8 B-R230.931 B-R233.562 B-R250.521 B-R2
23Porsche GT3 CupRobert Kelley 2+ carsGT2981:57.745 A-Q21:57.4401:57.745 A-Q21:58.760 A-R11:59.706 A-R1+1.876 A-R1125.1 A-R132.864 A-R133.998 A-Q250.578 A-Q2
24Dodge VIPERRobert Kelley 2+ carsGT2881:57.753 B-P1:57.5012:00.453 B-Q21:59.538 B-R22:02.474 B-R2+3.373 B-R292.9 B-Q131.983 B-P33.965 B-P51.553 B-P
25Nissan 300ZXJames SlechtaSTU751:59.183 A-Q21:59.1831:59.183 A-Q22:00.458 A-R22:01.009 A-R2+0.921 A-R2132.0 A-Q132.882 A-Q234.528 A-Q251.773 A-Q2
26Mazda MX-5Oscar JacksonSTU1611:59.707 B-R21:58.8881:59.707 B-R21:59.952 B-R2+1.112 B-R2103.9 B-R232.339 B-R234.219 B-R252.330 B-R2
27Mazda RX-7Michael LewisSTU322:00.248 A-R12:00.1792:00.248 A-R12:02.190 A-R2+1.431 A-R2130.4 A-R132.729 A-R134.570 A-R152.880 A-R1
28Mazda RX-7Wayne Graham >115%GT2962:00.512 B-R11:59.5332:01.239 B-Q12:00.512 B-R12:01.174 B-R1+1.175 B-R1100.1 B-R132.073 B-R134.881 B-R152.579 B-R1
29Mazda 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
30Mazda 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
31Mazda 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
32Mazda 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
33Mazda 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
34Mazda MX-5Dale ShoemakerSTU522:01.642 B-R22:01.1762:04.115 B-Q12:01.642 B-R22:02.793 B-R2+2.442 B-R2125.9 A-Q232.956 B-R234.983 B-R253.237 B-R2
35Mazda 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
36Mazda 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
37Mazda 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
38Mazda 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
39Mazda 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
40Mazda 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
41Mazda 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
42Mazda 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
43Mazda 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
44Mazda 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
45Mazda 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
46Mazda 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
47Mazda 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
48Mazda 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
49Mazda 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
50Mazda 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
51Mazda 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
52Mazda 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
53Mazda 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
54Mazda 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
55Mazda 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
56Mazda 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
Mazda MiataSM/STU311:41.720John Stott2:00.831William Wallis2:01.538Whitfield Gregg153.3John Stott26.218Max Logemann29.118Max Logemann43.340Max Logemann
Chevrolet CamaroGT231:42.698Tim Carroll1:42.698Tim Carroll1:44.128Tim Carroll149.2Jean Meynet28.543Jean Meynet29.839Tim Carroll44.262Tim Carroll
Ford MustangGT211:45.818Brad McAllister1:45.818Brad McAllister1:46.926Brad McAllister115.9Brad McAllister28.729Brad McAllister30.833Brad McAllister45.847Brad McAllister
Dodge ChallengerGT211:46.922Ben Valentine1:46.922Ben Valentine1:47.171Ben Valentine132.9Ben Valentine29.689Ben Valentine30.929Ben Valentine45.990Ben Valentine
Porsche GT3GT221:47.914Rocky Crocker1:47.914Rocky Crocker1:48.433Rocky Crocker155.7Rocky Crocker29.826Rocky Crocker31.456Rocky Crocker46.030Rocky Crocker
Swift Db6FF21:49.259Edward Erlandson1:55.247Johnnie Crean1:54.993Johnnie Crean124.5Johnnie Crean31.358Johnnie Crean32.841Johnnie Crean47.766Edward Erlandson
Chevrolet CorvetteGT211:49.904Igor Lyustin1:50.345Igor Lyustin1:49.904Igor Lyustin145.8Igor Lyustin30.271Igor Lyustin31.850Igor Lyustin47.568Igor Lyustin
Mazda RX-3STU11:50.913Tony Rivera1:50.913Tony Rivera1:52.737Tony Rivera135.2Tony Rivera30.415Tony Rivera32.456Tony Rivera47.999Tony Rivera
Mazda RX-7GT2/STU41:51.013Guy Laidig1:51.013Guy Laidig1:52.486Guy Laidig138.7Guy Laidig30.134Guy Laidig32.225Guy Laidig47.907Guy Laidig
Piper DL7-HondaFF11:51.118Eric Poulsen1:52.044Eric Poulsen1:51.118Eric Poulsen114.7Eric Poulsen30.276Eric Poulsen31.650Eric Poulsen48.818Eric Poulsen
BMW M3STU11:52.380Wilson Powell1:55.401Wilson Powell1:53.843Wilson Powell102.6Wilson Powell30.577Wilson Powell32.372Wilson Powell49.215Wilson Powell
SWIFT DB-FF11:53.098Edward Erlandson1:53.098Edward Erlandson1:54.741Edward Erlandson133.7Edward Erlandson30.951Edward Erlandson32.299Edward Erlandson49.791Edward Erlandson
Honda S2000STU11:53.640Rylan Hazelton1:55.834Rylan Hazelton1:53.640Rylan Hazelton134.8Rylan Hazelton30.582Rylan Hazelton32.779Rylan Hazelton49.779Rylan Hazelton
BMW 330STU11:56.492Sean Lovett1:56.492Sean Lovett1:57.049Sean Lovett133.7Sean Lovett31.816Sean Lovett33.669Sean Lovett50.941Sean Lovett
Dodge VIPERGT211:57.753Robert Kelley2:00.453Robert Kelley1:59.538Robert Kelley92.9Robert Kelley31.983Robert Kelley33.965Robert Kelley51.553Robert Kelley
Nissan 300ZXSTU11:59.183James Slechta1:59.183James Slechta2:00.458James Slechta132.0James Slechta32.882James Slechta34.528James Slechta51.773James Slechta
Mazda MX-5STU21:59.707Oscar Jackson2:04.115Dale Shoemaker1:59.707Oscar Jackson125.9Dale Shoemaker32.339Oscar Jackson34.219Oscar Jackson52.330Oscar Jackson
Mazda MiattaSM12:01.816William Rasmussen2:01.816William Rasmussen2:02.486William Rasmussen125.6William Rasmussen33.179William Rasmussen34.870William Rasmussen53.902William Rasmussen

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

STU E&O STU NA Weight Chart.

#33737 from Eric Heinrich · Rule change · TB 23-03 (2023-03 Fastrack)

Summary

fasterSTU minimum weight chart updated: 2450cc to 2595lbs, 2600cc to 2710lbs.

As printed in Fastrack

In STU, GCR Section 9.1.4.1.H.1. chart, Factory Engine Displacement (cc) Minimum Weight (lbs), change as follows:
"2450 2596 2595"
"2600 2860 2710"

FF Add Fast Forward Part Numbers for Honda Fit Engine

#33752 from Formula/Sports Racing Committee · Rule change · TB 23-03 (2023-03 Fastrack)

Summary

wordingFF Honda Fit engine adds Fast Forward part number alternatives for intake, exhaust, oil system, and scavenge pump components.

As printed in Fastrack

In FC/FF, GCR section 9.1.1.B.14.a.6, change as follows:
"For all Honda part numbers in these specifications, superc seding part numbers are considered equivalent.
In FC/FF, GCR section 9.1.1.B.14.f.5, change as follows:
"Cylinder head breather restrictor must be used as supplied by HPD or Fast Forward, unmodified.: HPD PN: 15262-F21S-A200; Fast
Forward PN: FF200-503."
In FC/FF, GCR section 9.1.1.B.14.k.2, change as follows:
"The upper manifold, air box and throttle body assembly must be used as delivered from Honda, HPD, or Fast Forward as noted
below."

Show 35 more lines

In FC/FF, GCR section 9.1.1.B.14.k.2, insert as follows:
"a. Intake manifold: HPD PN: 17210-F21S-A210; Fast Forward PN: FF200-201.
b. Throttle body: Honda Fit: PN: 16400ZZ5024; HPD PN: 16400ZZ5024; Fast Forward PN: FF200-104.
c. Throttle lever: HPD PN: 17330-F21S-A210; Fast Forward PN: FF200-101."
In FC/FF, GCR section 9.1.1.B.14.k.3, change as follows:
"All gaskets and sensors utilized on the inlet manifold from head to throttle body must be Honda Fit OEM, or HPD supplied or Fast
Forward as noted below.
a. Gasket In. manifold: HPD PN: 17105-RB0-004, Honda Fit OEM.
b. Gasket, EGR chamber cover: HPD PN: 17146-RB0-004, Honda Fit OEM.
c. Gasket In. port: HPD PN: 17115-RB0-007, Honda Fit OEM.
d. Gasket, restrictor: HPD PN: 17399-F21S-A200, (2 required) HPD; Fast Forward PN: FF200-109. Two required."
In FC/FF, GCR section 9.1.1.B.14.k.5, change as follows:
"The Honda Fit engine is required to have an HPD supplied air inlet restrictor supplied by HPD or Fast Forward: HPD PN: 17344-
F21S-A201; Fast Forward PN: FF200-110, with internal diameter of 30.5mm and thickness of 3.175mm (0.125 inches) correctly
installed within the intake system."
In FC/FF, GCR section 9.1.1.B.14.m.1, change as follows:
"The exhaust manifold must be as supplied by HPD or Fast Forward:, HPD part # PN: 18150-F21S-A200 or # PN: 1818 50-F21S-B200;
Fast Forward PN: FF500-001 or PN: FF500-002."
In FC/FF, GCR section 9.1.1.B.14.n.1, change as follows:
"The oil pan, baffle plate, and scavenge pump filter fittings must be as supplied by HP or Fast Forward as noted below. No
modifications are permitted.
a. Oil pan: HPD PN: 11200-F21S-A210 or PN: 11200-F21S-C240; Fast Forward PN: FF100-201A or PN: FF100-201B.
b. Oil pan baffle plate: HPD PN: 11221-F21S-A210; Fast Forward PN: FF100-202.
c. Oil scavenge pump filter fittings (2 required): HPD PN: 15180-F21S-A210; Fast Forward PN: FF100-204."
In FC/FF, GCR section 9.1.1.B.14.n.3, change as follows:
"The scavenge pump and internal scavenge pump parts must be as supplied from HPD or Fast Forward as noted below."
In FC/FF, GCR section 9.1.1.B.14.n.3, change as follows:
"b. Rotor outside diameter: HPD 44.400mm (1.748 inches):; Fast Forward 40.640mm (1.600 inches).
c. Scavenge pump rotor set: HPD PN: 15450-F21S-A20; Fast Forward PN: FF100-110.
d. Oil pump: HPD PN: 15100-F21S-A200; Fast Forward PN: FF100-100A.
e. Scavenge pump cartridge: 15111-F21S-A21; Fast Forward PN: FF100-127.
f. Scavenge pump port A: HPD PN: 15137-F21S-A20; Fast Forward PN: FF100-101.
g. Scavenge pump port B: HPD PN: 15139-F21S-A20; Fast Forward PN: FF100-102.
h. Scavenge pump shaft: HPD PN: 15510-F21S-A20; Fast Forward PN: FF100-103.
i. Scavenge pump front cover: HPD PN: 15070-F21S-A21; Fast Forward PN: FF100-104."

GT2 Adding Ginetta G56 GTA Factory ProTune for GT2 Class

#33825 from Robert Mueller · Rule change · TB 23-04 (2023-04 Fastrack)

Summary

unclearGT2 Ginetta G56 GTA may now use Factory installed ProMap ECU Map.

As printed in Fastrack

In GT Cars - Ginetta, Ginetta G56 GTA, add to Notes as follows:
"May use Factory installed ProMap ECU Map."

STU Alternate OEM Miata Intake Manifold

#33827 from Brandon Steinhauer · Rule change · TB 23-04 (2023-04 Fastrack)

Summary

wordingSTU Mazda BP5A classified at 1839 cc maximum displacement, 2023-04-01.

As printed in Fastrack

In STU Spec lines, classify Mazda BP5A as follows:
STU Maximum Displacement (cc's) Minimum Weight Notes
Mazda BP5A 1839 Chart May use engine in its entirety or specific
components from the engine.

GT2 Request to class 2011 Porsche Cayman S

#33771 from Coyote Black · Rule change · TB 23-05 (2023-05 Fastrack)

Summary

cars added2009-2012 Porsche Cayman S classified in GT2, 3.4L, RWD, no PDK transmission allowed.

As printed in Fastrack

In GT Cars - Porsche, classify Porsche Cayman ‘S’ as follows:
GT Cars - Porsche
Model Years Body Style Drive-
line
Wheel-
base (in)
Notes
Porsche Cayman ‘S’ 09-12 2 dr. Coupe RWD 95.08 3.4L No PDK Transmission

GT2 Please classify Fields Cardinal V8

#33784 from James Rogersn · Rule change · TB 23-05 (2023-05 Fastrack)

Summary

cars addedFields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight.

As printed in Fastrack

In GT Spec Lines, GT1 Cars - Fields Cardinal, classify Fields Cardinal V8 as follows:
GT1 Cars – Fields Cardinal
Model Years Body Style Drive-
line
Wheel-
base (in)
Notes
Fields Cardinal V8 2023 2 Dr. RWD 92.0 Roll Cage MUST be modified to comply with

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GCR Section 9.4.
In GT Spec Lines, GT1Engines - classify Ford V8 as follows:
GT1 Engines - Ford
Engine
Family
Engine Type Bore x

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

GT2 appendix letter #33635

#34206 from Ian Barberi · Rule change · TB 23-06 (2023-07 Fastrack)

Summary

wordingGT2 BMW engines: 3.4L 6-cyl at 2575 lbs, 4.0L V8 at 2900 lbs, 4.5L V8 at 2950 lbs, 5.0L V8 at 3000 lbs; S54 with 97mm stroke permitted at 2800 lbs.

As printed in Fastrack

In GT2-ST Spec Lines, BMW E46 M3 & E36 / BMW Z3 / BMW 5000cc V8, change notes as follows:
"The 3.4 liter 6 cyl. (87.0 bore x 93.0 stroke) is permitted at 2575lbs. 4.0L V8 permitted at 2900lbs. 4.5L V8 permitted at 2950lbs.
5.0L V8 permitted at 3000lbs. Flossman body kit permitted as found at http://www.racingpartsbmw.de/start/eng/start.htm.
Trans Am SGT spec: Regular shifter 3000 lbs., paddle shifter plus 150 lbs. 95mm S54 crankshaft @ +150lbs. Lang Racing part#
S54-95mm-StrokerCrk.
S54 engine is permitted a 97mm stroke crankshaft (part #VAC-SC-S54) @2800lbs."

GT2 Remove Weight and Restrictor Penalty for Corvette C7 Body

#34342 from Jorge A Nazario · Rule change · TB 23-06 (2023-07 Fastrack)

Summary

fasterGT2 Corvette C7 restrictor increases from 73mm to 77mm flat plate, removing weight penalty.

As printed in Fastrack

In GT2/ST, Chevrolet Corvette (2014-2019) change as follows:
Restrictor: "73 7mm flat plate"

STU 2022 Toyota GR Cup for STU

#34449 from Club Racing Board · Rule change · TB 23-06 (2023-05 Fastrack)

Summary

cars addedToyota GR Cup and GR86 Cup (2022-) newly classified in STU at 2700 lbs with 2387 cc engine.

As printed in Fastrack

In STU Spec Lines, Toyota GR Cup (2022-), classify as follows:

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

GT2 GT2 Mazda 20B 3 rotor ENO

#34765 from Grand Touring Committee · Rule change · TB 23-09 (2023-09 Fastrack)

Summary

fasterGT2 Mazda 20B 3 rotor loses 220 lbs, to 2280, consolidating two spec lines.

As printed in Fastrack

In GT2 Spec Lines, Engines - MAZDA, combine both 20B to one spec lines and keep the following:
Weight: "2500 2280"
Notes: "Must run +100 lbs. for Grand Am transaxle and independent rear suspension. Must comply with all other GT2 rules."

GT2 Late E & O

#34966 from Scotty B White · Rule change · TB 23-10 (2023-10 Fastrack)

Summary

fasterGT2-ST Dodge Viper including Comp Coupe, ACR/ACR-X with VRL front fascia loses 100 lbs.

As printed in Fastrack

RM 23-10 GT2-ST Dodge Viper, incl Comp Coupe, ACR/ACR-X VRL Front Fascia
As an Errors and omissions fix to what was originally intended for these cars, the Club Racing Board and Board of Directors have
approved the following:
In GT2-ST, Dodge Viper, incl Comp Coupe, ACR/ACR-X add VRL front fascia -100lbs to all Spec Lines.

GT2 Errors in GTCS Headings and Use of the Terms Category and ClassChange existing GTL and GTA Rules

#34453 from David Gomberg · Rule change · TB 23-12 (2023-12 Fastrack)

Summary

wordingGTL spec lines moved to contiguous position with GT2 and GT3; GTA category and spec lines renumbered and moved behind GTL.

As printed in Fastrack

from the current (or before) Table of Contents (TOC), to what is shown in the after TOC.
GTL spec lines will now be contiguous with GT2 and 3 spec lines.
GTA category and spec lines will be moved and renumbered behind GTL. GTA Section will not change but page numbers will, (as
shown in Red italics).
9.1.2.F. GT-2, 3, LITE Category Specifications 314
GT2 Cars 327
GT2/ST 341
GT3 Cars 348

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GTL Cars 364
GTA Cars 377
P2 Engine Table B.1
2010 and older
Stock Kawasaki
38.5mm
minimum width 52 inches. AMAC-AM5:
minimum width 54 inches.
P2 Engine Table B.1
2008 and older
Stock Engine Suzuki,
Yamaha,
Honda, BMW
38.5mm
P2 Engine Table B.2 Not required
P2 Engine Table B.3 38.5mm
Modified Engine
950 lbs.
1005cc max
P2 Engine Table B.1 37mm
P2 Engine Table B.2 Not required
P2 Engine Table B.3 39mm
Stock Engine
1050 lbs.

GT2 Dodge Viper Gen 3 hybrid Kit Update Request

#35200 from Sean McCann · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

slowerGT2-ST Dodge Viper hybrid kit restrictor reduced from 50mm to 45mm flat plates.

As printed in Fastrack

In GT2-ST Spec Lines, Dodge Viper, incl Comp Coupe, ACR/ ACR-X change NOTES as follows:
8300 OEM: "Stock OEM engine. Engine long block, valve train, and intake system must meet stock, shop manual specifications.
Hybrid update including Mopar Performance Part #P5156137. May use Mopar part #5038554AF (Gen 5 Intake Manifold
manifold allowed with (2) 55mm flat plates) and 8.4L mechanical throttle body allowed. VRL Front Fascia -100lbs."
8300: "Hybrid update including Mopar Performance Part # P5156137, Mopar part #5038554AF manifold and 8.4L mechanical
throttle body allowed using (2) 50 45mm flat plate restrictors. VRL Front Fascia –100lbs."
8400: "Intake and Throttle Body from Mopar Performance Part # P5156137allowed using (2) 50 45mm flat plate
restrictors. , Mopar part #5038554AF manifold (Gen 5 Intake Manifold allowed with (2) 50mm flat plates) VRL Front Fascia -

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100lbs 8400 OEM 3225 Stock OEM engine. Engine long block."

FF Honda Fit Oversize Piston Rings

#35305 from Doug Learned · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

wordingFF Honda Fit gains Fast Forward FF800-100 oversize piston ring pack option.

As printed in Fastrack

In FF, GCR section 9.1.1.B.14.e.3.a, add the following:
"The standard ring pack, PN 13011-RB1-004 (Riken) or 13011-RB1-006 (Nippon), or the oversize ring pack, PN 13021-RB7-Z01
(Riken), or 13021-RB7-Z02 (Nippon), or FF800-100 (Fast Forward), may be used."

STU ST Electric-Assisted Steering Systems

#35066 from Jose Osiris Pena · Rule change · TB 24-02 (2024-01 Fastrack)

Summary

wordingSTL and STU power steering rules clarified to permit electric-assisted and hydraulic-assisted steering systems.

As printed in Fastrack

In GCR, Section 9.1.4.M.16., change as follows:
"Power steering may be modified in any of the following ways:
a. disconnected , pump, belt, pulley, and hoses may be removed. Hoses may also be looped. Steering rack or box may be
modified internally to work without pump.
b. an OEM manual steering rack for that model may be fitted
c. an electric power steering pump may be fitted
d. an OEM electric-assisted steering system may be used or any column mounted electric steering assist may be used
e. an OEM hydraulic-assisted steering system may be used"

GT2 Rear Blade Spoiler Clarification

#35261 from Butch Kummer · Rule change · TB 24-02 (2024-01 Fastrack)

Summary

fasterGT1, GT2, GT3, GTL, GTX rear spoiler maximum surface area limit of 295.0 square inches removed.

As printed in Fastrack

In GCR Section 9.1.2.G (GTA Category Specifications), change as follows:
“9.1.2.G.III.I
The single-plane rear spoiler must be mounted at an angel angle from 50 to 75 degrees (perpendicular to the ground
being 90 degrees) and may not extend beyond the rear bumper when viewed from directly above the rear
bumper. Spoilers must be a minimum of .063 aluminum or Lexan and may vary in overall height to match the contours
of the bodywork. The rear spoiler dimensions shall not exceed 59.0 inches wide by 5.0 inches in height, (measured on
the material surface) , or 295.0 square inches total surface area. Braces to prevent spoiler deflection are allowed, but
may serve no other purpose.”

GT2 REDUCE C6 CORVETTE WEIGHT WITH OEM 7 LITER ENGINE REDUCE BY 150LB

#35385 from Mike McGinley · Rule change · TB 24-02 (2024-02 Fastrack)

Summary

fasterGT2 Chevrolet Corvette 7011 OEM 7 liter weight reduced 150 lbs, to 3125 lbs.

As printed in Fastrack

In GT2/ST Chevrolet Corvette 7011 OEM change weight as follows:
“3275 3125“

GT2 GT Direct Injection allowance and rules

#35437 from Grand Touring Committee · Rule change · TB 24-02 (2024-01 Fastrack)

Summary

fasterGT1/GT2/GT3/GTL/GTX Direct Injection now permitted if OE, using only OE pump, hoses, injectors.

As printed in Fastrack

In GCR, Section 9.1.2.F.7.5.E. change as follows:
“Direct Injection is not permitted only if it came OE and must be installed using only OE high pressure pump(s), hard and
soft hoses and injectors.”

GT2 GT2/3 remove Direction Injection not allowed in Spec line notes

#35439 from Grand Touring Committee · Rule change · TB 24-02 (2024-02 Fastrack)

Summary

fasterGT2/3 Nissan, Mazda, Mitsubishi 4G93, QR25DE/DD, QE25DE/DD Direct Injection now permitted per 9.1.2.F.7.5.E.

As printed in Fastrack

In GT2/3 modify Spec Line notes as follows:
GT2:
Nissan: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E.”
GT3:
Mazda: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E.”
Mitsubishi 4G93: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E. ”
Nissan QR25DE/DD 1988cc: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E.”
Nissan QE25DE/DD 2489cc: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E.”

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

GT2 Classify Corvette C8 (2020- ) into GT2/ST

#33759 from Andrew Aquilante · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

cars addedChevrolet Corvette C8 (2020–) classified into GT2-ST with 6162cc displacement, 3300 lbs minimum weight, 71mm restrictor.

As printed in Fastrack

In GT2 Spec Lines, classify Chevrolet Corvette C8 (20-) as follows:
GT2-ST Maximum Displacement Minimum Weight Restrictor Notes
Chevrolet Corvette C8
(20-)
6162 3300 71mm -
Flat Plate
LT2 engine.

Applies to Chevrolet Corvette on this page: Igor Lyustin

GT2 Requesting classification for a 2015 Mitjet ST in GT2

#35408 from Jim Froula · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

cars added2015 Mitjet ST added to GT2, must run per VTS specifications with complete FIA form CdM008.

As printed in Fastrack

In GT2 Spec Lines, GT Cars - MITJET ST, classify MITJET ST as follows:
GT Cars – MITJET ST
Model Years Body Style Drive-
line
Wheel-
base (in)
Notes
MITJET ST 2015 RWD 94.5 Must run per VTS specifications. Must have

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complete car Specifications (FIA form
CdM008) at every entered race event.

STU Letter #35397 addendum

#35453 from Aaron Fitzsimmons · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

wordingSTU Mini Cooper S SC: alternate LEAP OMICRON hood scoop LEP-OMICRON3 permitted.

As printed in Fastrack

In STU Spec Lines, Mini Cooper S SC with Minimum Weight 1900 and 2100, add to Notes:
"Alternate LEAP OMICRON hood scoop part # LEP-OMICRON3 is permitted."

STU S54 Drysump

#35464 from Macey Urso · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

wordingSTU BMW S54 B32 OEM now permits dry sump oiling system.

As printed in Fastrack

In STU Spec Lines, BMW S54 B32 OEM, add to Notes as follows:
"Dry Sump oiling system permitted."

GT2 Request for Spec Line 1010 Reconsideration

#35009 from Kristofer Olson · Rule change · TB 24-05 (2024-05 Fastrack)

Summary

slowerGT2-ST Acura NSX minimum weight raised to 3000 lbs, restrictor increased to 45mm TIR.

As printed in Fastrack

In GT2-ST Spec Lines, Acura NSX, change as follows:
Minimum Weight: "2700 3000"
Restrictor: "43 45mm TIR"

GT2 Request to Eliminate the FPR from the Corvette (-2013) with LS2

#35878 from Michael Quattlebaum · Rule change · TB 24-05 (2024-05 Fastrack)

Summary

fasterGT2-ST Corvette 14-19 LS2 restrictor increases from 78mm to 80mm flat plate.

As printed in Fastrack

In GT2-ST Spec Lines, Chevrolet Corvette (14-19), change Restrictor as follows:
"78 80mm flat plate"

GT2 GT2-ST Rule Clarification

#36093 from Dominic Starkweather · Rule change · TB 24-07 (2024-07 Fastrack)

Summary

wordingGT2-ST allows aftermarket replacement differential housings if exact equivalents.

As printed in Fastrack

In GCR Section, Appendix K. 2012.M2, add the following:
"After market replacement differential housings are permitted as long as they are an exact equivalent."

GT2 GT4 cars may run in GT2-ST

#36235 from Grand Touring Committee · Rule change · TB 24-07 (2024-07 Fastrack)

Summary

cars addedGT4 cars now permitted in GT2-ST with factory restrictor, must comply with 2012 STO rules, slicks allowed with 100-pound penalty.

As printed in Fastrack

In 9.1.2. GT2 Spec Lines, GT3 Cars, change Note as follows:
"Note: All GT4 cars are permitted to compete in GT2-ST provided they use a factory supplied power stick or Pro Series
required restrictor. Must have GT4 rules in possession at all race events. Cars must comply with 2012 STO rules as
stated in Appendix K of the GCR. Engine Displacements in this table are nominal. Each competitor shall have available
definitive documentation (e.g., factory manual) of the original displacement for the engine used. Slicks allowed on all
GT2/ST cars with a 100-pound weight penalty."

STU RWD Turbo Disadvantage

#36255 from David Fiorelli · Rule change · TB 24-08 (2024-08 Fastrack)

Summary

fasterSTU RWD turbo cars no longer required to reduce restrictor by 1 mm from table.

As printed in Fastrack

In GCR, Section 9.1.4.1.H.3 - Inlet Restrictor (mm) Minimum Weight (lbs) table, change as follows:
"RWD cars must reduce restrictor 1 mm from this table"

SM SMX Camera Rule Correction

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

Summary

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

As printed in Fastrack

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)

Summary

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

As printed in Fastrack

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)

Summary

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

As printed in Fastrack

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)

Summary

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

As printed in Fastrack

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."

FF Update to FF EGR Blanking Plate Rule

#36633 from Matt Boian · Rule change · TB 24-10 (2024-10 Fastrack)

Summary

wordingFF VTEC activation valve must function; EGR blanking plate rule clarified with Fast Forward part numbers.

As printed in Fastrack

In FF, GCR section 9.1.1.B.14.r.1, change as follows:
"All emission control devices must be removed and blocked off by the blanking plate provided by HPD or Fast Forward as noted
below, except for the VTEC activation valve. The VTEC activation valve must be retained; and it must be functioning. No
modifications are permitted.
a. EGR Plate: Fast Forward PN: FF200-301.
b. EGR Port Cover: Fast Forward PN: FF200-302."

FF Change FF/FC Weight with Sequential Gearbox

#36651 from Robert Wright · Rule change · TB 24-11 (2024-11 Fastrack)

Summary

fasterFF and FC cars with sequential gearbox must add 10 lbs. to minimum weight, down from 25 lbs.

As printed in Fastrack

In FF, GCR section 9.1.1.B.20.A.3, change as follows:
"Cars running with a sequentially shifted gear box shall must add 25 10 lbs. to minimum weight."
In FC, GCR section 9.1.1.B.20.B.4, change as follows:
"Cars running with a sequentially shifted gear box shall must add 25 10 lbs. to minimum weight."

STU R53 15% Pulley Request

#36980 from Aaron Fitzsimmons · Rule change · TB 24-11 (2024-11 Fastrack)

Summary

slowerSTU Mini Cooper S SC 1900 restricts to 2.565 diameter pulley; 2100 allows 2.285 diameter pulley.

As printed in Fastrack

In STU Spec Lines, Mini Cooper S SC, add to notes:
1900: "Stock supercharger pulley. 2.565 diameter."
2100: "JCW Pulley permitted. May run a 2.285 diameter pulley."

FF Alternative Oversize Honda Fit Pistons

#37064 from Formula/Sports Racing Committee · Rule change · TB 24-11 (2024-11 Fastrack)

Summary

wordingFF Honda Fit allows Fast Forward 0.25mm oversize pistons PN FF800-110 as alternative; piston diameter spec clarified to 2.8835 inches.

As printed in Fastrack

In FF, GCR section 9.1.1.B.14.e.1, change as follows:
"Honda Fit OEM standard size pistons, PN: 13010-RB1-000, or Honda Fit OEM 0.25mm oversize pistons, PN: 13020-RB7-Z00, or
Fast Forward 0.25mm oversize pistons, PN: FF800-110, may be used."
In GCR section 9.1.1.B.14.e.2, change as follows:
"a. Maximum standard piston diameter, measured at a point 16mm from the bottom of the skirt: 73.240mm
(2.8834 2.8835 inches).
b. Centerline of wrist pin to crown maximum: 26.21mm (1.032 inches).
c. Maximum overall height from skirt to crown edge: 47.80mm (1.882 inches).

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d. Minimum weight: 198.0 grams (6.984 ounces).
e. Minimum weight of piston pin: 66 grams (2.25 ounces).
f. Combined minimum weight of piston, piston pin and connecting rod: 543.5 grams (18.85 ounces).
g. Combined minimum weight of piston, wrist pin, and circlips: 267 grams (9.418 ounces).
h. Centerline of wrist pin to crown edge: 26.289mm (1.035 inches).
i. Ring groove widths:
Top ring groove: 1.003mm (0.0395 inches).
Middle ring groove: 1.016mm (0.0400 inches).
Oil ring groove: 1.981mm (0.0780 inches).
j. Ring groove distance from wrist pin center to bottom of groove:
Top ring groove: 19.63mm (0.7730 inches).
Middle ring groove: 15.29mm (0.6020 inches).
Oil ring groove: 10.91mm (0.4295 inches)."

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)

Summary

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

As printed in Fastrack

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."

STU Request to Remove Miata Hubs from General category

#37138 from Christopher Childs · Rule change · TB 24-12 (2024-12 Fastrack)

Summary

wordingSTL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval.

As printed in Fastrack

In GCR, Section 9.1.4.M.18., change as follows:
"18. Allow alternate front wheel front hubs, Mazda Motorsports Development Part #0000-04-5HUB-S1, for the 90-05 Mazda
Miata: Mazda Motorsports Development Part #0000-04-5HUB-S1."

STU BMW N54/N55 Engine Allowance

#37146 from Martin Sarukhanyan · Rule change · TB 24-12 (2024-12 Fastrack)

Summary

slowerSTU BMW N54/N55 turbo inlet restrictors now required per GCR definition; turbo swapping prohibited.

As printed in Fastrack

"Turbo inlet restrictors designed per GCR Appendix F Technical Glossary definition of “Turbo Inlet Restrictor” may be required;
see table 9.1.4.1.H.h.2 3. Swapping of turbochargers between engine makes and models is prohibited. Supercharged cars may be
approved on a case-by-case basis; twin turbo engines are allowed on a case-by-case basis only. Contact the Road Racing
Technical Office for details. Twin turbo engines may be converted to single turbo using one of the allowed alternate turbos (see
9.1.4.1.H.3 2). Aftermarket turbocharger and supercharger kits will be allowed on a case-by-case basis.

STU Audi 1.8t Wagon STU Table B

#36685 from Mike McLaughlin · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

fasterSTU Audi 1.8T wagon deleted; Porsche 944 1800 weight to Chart, turbo inlet restrictor removed.

As printed in Fastrack

In STU Spec Lines, Table B: Alternate Vehicle and Engine Requirements, delete Audi/VW 1.8 Turbo in its entirety.
In STU Spec Lines, Table B: Alternate Vehicle and Engine Requirements, Porsche 944 w/Max Displacement 1800, change as
follows:
Weight: "3050 Chart"
Notes: "VW/Audi 1.8L 35mm turbo engine permittedinlet restrictor required."

GT2 Panoz Esperante GTS BOP

#36686 from Brian Goldburg · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

cars addedGT2 Panoz Esperante GTS adds 2013-2016 Ford EcoBoost Twin Turbo V-6 3496cc engine, 2600 lbs.

As printed in Fastrack

In GT2 SPEC LINES, GT Engines - PANOZ, classify 2013-2016 Ford EcoBoost Twin Turbo as follows:
GT Engines – PANOZ
Engine
Family
Engine Type Bore x
Stroke
(in.)
Disp.

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(CC)
Head Type Valves /

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

GT2 Correct language regarding OEM Areo Devices

#37137 from Christopher Childs · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

wordingTA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof requirement.

As printed in Fastrack

In GCR, Section APPENDIX L. 2013 TA2 TECHNICAL REGULATIONS, B.2.c., change as follows:
"B. Aerodynamic Devices
2. Rear wing
c. The entire rear wing assembly, including the end plates and any Gurney flap, shall be mounted level
with, or below, the peak of the roof. OEM aerodynamic devices do not need to adhere to the height rule."

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

GT2 GT2 Sunbeam Tiger Alternate Carburetor

#37198 from Tom Patton · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

inductionGT2 Sunbeam Tiger gains Holly 650 cfm carburetor alternate options PN #80541-1 and #80541-2.

As printed in Fastrack

In GT2 Spec Lines, GT Engines - SUNBEAM, add to Fuel Induction as follows:
"Carburetors(s) Holly 650 cfm PN #80541-1 and PN #80541-2"

STU Merger GT3 to STU

#37486 from Club Racing Board · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

wordingSTU-GT3 reclassified as STU-GT3U effective January 1, 2026.

As printed in Fastrack

In STU, Table C, change STU-GT3 charge as follows:
"(Effective January 1, 2026) TABLE C: STU-GT3U"

STU GT3 TCR Tire allowance

#37494 from Club Racing Board · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

slowerSTU GT3 TCR gains 275-width tire option with 100 lb weight penalty, but not in A compound.

As printed in Fastrack

In STU, Table C, GT3 TCR, add to Notes the following:
"May run DOT approved tire with maximum section width of 275 with 100 pound weight adder. May not run A compound with
275."

GT2 GT2/ST - Remove Aftermarket/Racing ABS penalty

#36538 from Jorge A Nazario · Rule change · TB 25-02 (2025-02 Fastrack)

Summary

fasterGT2 STO aftermarket ABS weight penalty reduced from 100 lbs to 50 lbs.

As printed in Fastrack

In GCR, Appendix K. 2012 STO Rules, O.9., change as follows:
"May run OEM ABS or convert to an aftermarket ABS controller with 100 50 lb. weight penalty."

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

GT2 Hood Bulge allowed

#37000 from Gordon Leslie · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

unclearGT2 Pontiac Fiero changes from FWD to RWD; hood bulge permitted for front engine relocation.

As printed in Fastrack

In GT2 Spec Lines, GT2 Cars - PONTIAC, Fiero, change as follows:
Drive-line: "FWD RWD"
Add to Notes: "Hood bulge permitted as requested for front engine relocation only."

STU BMW N54/N55 Engine Allowance Follow Up

#37447 from Martin Sarukhanyan · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

engineSTU BMW N54/N55 3.0L classified at Chart +3% minimum weight; N54 twin turbo not allowed.

As printed in Fastrack

In STU Spec Lines, Table A, classify BMW N54/N55 as follows:
STU Maximum Displacement
(cc's) Minimum Weight Notes
BMW N54/N55 3.0 Chart +3% (DI) Short blocks, heads, and intakes may be
freely swapped within these engine
designations. N54 twin turbo not allowed

GT2 OEM Wing Adjustment

#37590 from Christopher Childs · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

slowerTA2 and STO OEM wings no longer exempt from rear wing height rule at roof peak.

As printed in Fastrack

In GCR, Section APPENDIX L. 2013 TA2 TECHNICAL REGULATIONS, B.2.c., change as follows:
"The entire rear wing assembly, including the end plates and any Gurney flap, shall be mounted level with, or below, the peak of
the roof. OEM aerodynamic devices do not need to adhere to the height rule."
In GCR, Section APPENDIX K. 2012 STO GENERAL TECHNICAL REGULATIONS, D.4.b., add the following:
"Factory wings, and spoilers, and roof vortex generators are permitted, but must be removed if an approved aftermarket wing is
installed. OEM aerodynamic devices do not need to adhere to the height rule."

STU STU Mini Cooper pulley size clarification re: letter #36980

#37717 from Aaron Fitzsimmons · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

fasterSTU Mini Cooper S SC supercharger pulley diameter reduced from 2.285 to 2.185.

As printed in Fastrack

In STU Spec Lines, Mini Cooper S SC, add to notes:
2100: "May run a 2.285 2.185 diameter pulley."

STU Question About a Weight Modifier

#37782 from Peter St Pierre · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

fasterSTU Honda K20C1 Turbo I4 exempted from 3% DI weight adder in Spec Lines Table A.

As printed in Fastrack

In STU Spec Lines, Table A, Honda K20C1 Turbo I4, add to Notes the following:
"The 3% DI weight adder does not need to be applied."

FF Formula F Proposal to Invite Older Cars Via a Tire Rule Change

#37802 from Anthony Stefanelli · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

fasterFF allows older cars with rocker arm or outboard suspension to use bias ply slicks or VFF tires instead of radials.

As printed in Fastrack

In FF, GCR section 9.1.1.B.10.e, change as follows:
"Formula F shall be limited to the following tires (front tires may not be used as rears):
Dries:
Front - Hoosier R60A Radial 43322 or F1600 Radial 43321 185/60R13
Rear - Hoosier R60A Radial 43327 or F1600 Radial 43326 205/60R13
Wets:
Front - Hoosier Wet or W3 Radial 44421 185/60R13
Rear - Hoosier Wet or W3 Radial 44426 205/60R13

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Alternatively, Formula F cars with rocker arm suspension (e.g., Swift DB1, 1987-90 Reynard) and/or outboard suspension on at
least one chassis end may use the following tires:
Dries:
Front - Hoosier H43130 R60A 20.0 x 6.0-13 or H43164 R60A 20.5 x 7.0-13 bias ply slick
Rear – Hoosier H43307 R60A 22.5 x 7.2-13 bias ply slick
Wets:
Radial wets listed above
or
Front - Hoosier 44165 135/545-13 VFF
Rear - Hoosier 44170 165/580-13 VFF
Front tires may not be used as rears, and tires may not be mixed, i.e., radial tires may not be mixed with bias ply slick tires, bias
ply slick tires may not be mixed with VFF tires, and radial tires may not be mixed with VFF tires."

STU Increase Minimum Weight

#37919 from Club Racing Board · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

slowerSTU GT3U minimum weight increases 150 to 250 pounds.

As printed in Fastrack

In STU Spec Lines, Table C: STU-GT3U, change Minimum Weight as follows:
"150 250 pounds"

SM Clarify Tire Marking Regs

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

Summary

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

As printed in Fastrack

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."

STU Wheel Size Inconsistency

#38018 from David Fiorelli · Rule change · TB 25-05 (2025-05 Fastrack)

Summary

wordingSTU wheel width rules clarified: cars ≤2,850 lbs max 8 inches, cars >2,850 lbs max 9 inches.

As printed in Fastrack

In GCR, Section 9.1.4.1.F.1., change as follows:
"Wheels may not exceed 18 inches in diameter. or 8.0 inches in width for vehicles 2950 lbs. and under minimum allowed race
weight. Vehicles over 2850 minimum allowed race weight may use a 9 inch wide wheel. Cars equal to or less than 2,850 lbs.
minimum allowed race weight may not use wheels wider than 8 inches. Cars greater than 2,850 lbs. minimum allowed race
weight may not use wheels wider than 9 inches."

FF Page 228, FF tire rule 9.1.1.10.e

#38251 from Anthony Stefanelli · Rule change · TB 25-05 (2025-05 Fastrack)

Summary

tyres & wheelsFF adds rocker arm and outboard suspension cars optional bias ply and VFF tires; removes front-as-rear rule, adds mixing restrictions.

As printed in Fastrack

In FF, GCR section 9.1.1.B.10.e, change as follows:
"Formula F shall be limited to the following tires (front tires may not be used as rears):
Dries:
Front - Hoosier R60A Radial 43322 or F1600 Radial 43321 185/60R13
Rear - Hoosier R60A Radial 43327 or F1600 Radial 43326 205/60R13
Wets:
Front - Hoosier Wet or W3 Radial 44421 185/60R13
Rear - Hoosier Wet or W3 Radial 44426 205/60R13

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Alternatively, Formula F cars with rocker arm suspension (e.g., Swift DB1, 1987-90 Reynard) and/or outboard suspension on at
least one chassis end may use the following tires:
Dries:
Front - Hoosier H43130 R60A 20.0 x 6.0-13 or H43164 R60A 20.5 x 7.0-13 bias ply slick
or
Hoosier 44165 135/545-13 VFF
Rear – Hoosier H43307 R60A 22.5 x 7.2-13 bias ply slick
or
Hoosier 44170 165/580-13 VFF
Wets:
Radial wets or VFF tires listed above
or
Front - Hoosier 44165 135/545-13 VFF
Rear - Hoosier 44170 165/580-13 VFF
Front tires may not be used as rears, and tires may not be mixed, i.e., radial tires may not be mixed with bias ply slick tires, bias
ply slick tires may not be mixed with VFF tires, and radial tires may not be mixed with VFF tires."

STU Table C: STU-GT3U Clarification

#38268 from Club Racing Board · Rule change · TB 25-05 (2025-05 Fastrack)

Summary

fasterSTU Spec Line GT3U minimum weight reduced from plus 250 to plus 225 pounds; wheel and tire options clarified with weight adjustments.

As printed in Fastrack

In STU Spec Line, Table C: STU-GT3U, change as follows:
Minimum Weight: “Current GT3 race weight plus 250 225 pounds”
Notes: "DOT approved tire with maximum section width of 245. GT3 cars base wheel is a maximum of 15”x9”. 18”x9” wheels
allowd with a 3% weight addition. GT3 cars utilizing 15”x7” wheels are limited to a maximum section width of 225 with a 25
pound weight reduction"
"All GT3U (Majors and Runoffs) cars using up to 15"x7" wheels limited to 225 section width tires shall run at current GT3 race
weight plus 225lbs. All Gt3U cars shall run a DOT approved tire with a maximum section width of 245. GT3U cars are allowed
optional 15"x9" wheels with a 1.5% weight addition or up to 18"x9" wheels with a 3.0% weight addition to the total weight

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including the 225 lbs."

SM SMX Data Submission - Penalties

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

Summary

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

As printed in Fastrack

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."

SM Committee) SMX Penaly Clarification updated language

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

Summary

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

As printed in Fastrack

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."

STU 2.8-3.2L N/A Engine Allowances

#38007 from Ben Slechta · Rule change · TB 25-07 (2025-07 Fastrack)

Summary

unclearSTU 2.8-3.2L N/A engines now allow 245 max tire width; over 3150 lbs may run 275 with 2% weight penalty.

As printed in Fastrack

In GCR, Section 9.1.4.G.1, add the following:
"A maximum section width of 245 is permitted. Cars over 3150 lbs. may run a 275 tire with a 2% weight adder."

STU 2006-2015 Mazda Miata Intake Manifold

#38422 from German Candelario Candelario · Rule change · TB 25-07 (2025-07 Fastrack)

Summary

wordingSTU Mazda MZR may use Goodwin 61-2510 or Gato Performance 31972 intake manifold.

As printed in Fastrack

In STU, Table A, Mazda MZR (LF, L3, L5), change Notes as follows:
"May use Goodwin Part # 61-2510 or Gato Performance Part #31972 Intake manifold . "

STU Requesting Approval of the JDM Honda h23a

#38489 from Eric Fiest · Rule change · TB 25-07 (2025-07 Fastrack)

Summary

cars addedSTU Honda JDM H23a added, 2259cc displacement, minimum weight per Chart, must meet ST engine regulations.

As printed in Fastrack

In STU, Table B, classify Honda JDM H23a as follows:
STU Maximum Displacement (cc's) Minimum Weight Notes
Honda JDM H23a 2259 Chart Must meet all ST engine regulations.

GT2 Rear Deck Lid for Older Air-Cooled Porsche

#38506 from Justin Erion · Rule change · TB 25-08 (2025-08 Fastrack)

Summary

wordingGT2 Porsche 911 Coupe & Targa may use 993 3.8 RSR rear deck lid or approved aftermarket reproductions.

As printed in Fastrack

In GT2 Spec Lines, GT2 Cars-Porsche, 911 Coupe & Targa., add to Notes the following:
"Porsche 911-based race cars (911,963,994), the use of the 993 3.8 RSR rear deck lid/spoiler is permitted. Aftermarket
reproductions of the original Porsche Motorsports deck lid provided they faithfully replicate OEM dimensions and functionality,
are acceptable for use."

STU STU-TCR Adjustments

#38723 from Club Racing Board · Rule change · TB 25-08 (2025-08 Fastrack)

Summary

slowerSTU-TCR tire width increases to 275 with weight adder raised from 100 to 150 pounds.

As printed in Fastrack

In STU Spec Lines, Table C: STU-GT3U, GT3-TCR, change as follows: Remove the current TCR spec line and add the TCR spec lines
from GT3 that are being removed, adding the below to the notes.
"DOT approved tire with maximum section width of 245. May run DOT approved tire with maximum section width of 275 with
100 150 pound weight adder. May not run A-compound with 275. STU-TCR spitters and side valance must comply with
9.1.4.D.3.f. STU-TCR chassis ride height must comply with 9.1.4.1.A.1."

STU Lotus Weight Reduction

#38772 from Club Racing Board · Rule change · TB 25-08 (2025-08 Fastrack)

Summary

fasterSTL/STU Lotus weight reduced: Evora GT4 to 2700 lbs, Elise Cup R to 2250 lbs, Elise/Exige SC to 2450-2550 lbs.

As printed in Fastrack

In 9.1.2. GT2/ST Spec Lines, Lotus Evora GT4, change Weight as follows:
"2750 2700"
In STU Table B: Alternate Vehicle and Engine Allowances, change Weight as follows:
Lotus Elise Cup R: "2300 2250"
Lotus Elise SC/ Lotus Exige SC: "2300 2550
2500 2450"

STU Lotus Weight Reduction E&O

#38919 from Club Racing Board · Rule change · TB 25-09 (2025-09 Fastrack)

Summary

fasterSTU Lotus Elise SC and Exige SC weight reduced from 2450 to 2250 lbs.

As printed in Fastrack

In STU Table B: Alternate Vehicle and Engine Allowances, change Weight as follows:
Lotus Elise SC/ Lotus Exige SC: "2450 2250"

STU Non-Homologated Engine Swaps - Specifically K24A2 w/ Honda CRZ

#38746 from William Rori · Rule change · TB 25-09 (2025-09 Fastrack)

Summary

slowerSTU Honda K24 engine swap weight increases by 2% effective November 1, 2025.

As printed in Fastrack

In STU Spec Lines, Table B: Alternate Vehicle and Engine Allowances, Honda K24, change Weight as follows:
"(Effective 11/1/2025) Chart + 2%"

STU Turbo Inlet Restrictor Table

#38961 from John Weisberg · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

slowerSTU 36mm restrictor allows 2830 lbs (up 10 lbs from 2820); 37mm allows 2980 lbs (down 5 lbs from 2985).

As printed in Fastrack

In GCR, Section 9.1.4.H.3, change chart as follows:

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

STU 275 Tire Rule

#38983 from Peter Federlin · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

slowerSTU cars over 3150 lbs lose 275-tire option with 2% weight adder.

As printed in Fastrack

In GCR, Section 9.1.4.G.1., change as follows:
"A maximum section width of 245 is permitted. Cars over 3150 lbs. may run a 275 tire with a 2% weight adder."

STU STU Honda Engine weight penalty

#39375 from Super Touring Committee · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

fasterSTU Honda K20 and K24 engines lose 2% minimum weight penalty.

As printed in Fastrack

In STU Spec Lines, Table B: Alternate Vehicle and Engine Allowances, change Minimum Weight as follows:
Honda K20: "Chart + 2%"
Honda K24: "Chart + 2%"

GT2 Additional Body Options to Replace Older Stock Car Bodies

#39086 from Samuel Daniels · Rule change · TB 26-01 (2026-01 Fastrack)

Summary

cars addedGT2 adds Cadillac CTS, Chevrolet Impala/Malibu/Monte Carlo/SS, Dodge Intrepid, Ford Fusion/Taurus, Lincoln MKS, Pontiac G8/GTO/Grand Prix, Toyota Camry, and Gen late Model Stock Car bodies.

As printed in Fastrack

In GCR, Section 4.8.4.2.1., add the following:
"Cars in the class must use 1997, through current year, commercially available stock car bodywork. The following make/model
bodies are allowed:
1. Cadillac CTS
2. Chevrolet Impala
3. Chevrolet Malibu
4. Chevrolet Monte Carlo
5. Chevrolet SS

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6. Dodge Intrepid
7. Ford Fusion
8. Ford Taurus
9. Lincoln MKS
10. Pontiac G8
11. Pontiac GTO
12. Pontiac Grand Prix
13. Toyota Camry
Gen late Model Stock Car Bodies are allows:
1. Chevrolet Camaro
2. Ford Mustang
3. Toyota Camry"

FF Formula F Alternative Tire Rule Proposed Clarifications

#39281 from Jay Messenger · Rule change · TB 26-01 (2026-01 Fastrack)

Summary

wordingFF clarifies alternative tire eligibility for cars homologated 1989 or earlier with rocker arm or outboard suspension on all four corners.

As printed in Fastrack

In FF, GCR section 9.1.1.B.10.e, change as follows:
"Alternatively, Formula F cars with rocker arm suspension (e.g., 1987-90 Reynard, Swift DB1,) and/or outboard suspension on at
least one chassis end homologated in 1989 or earlier with any combination of rocker arm or outboard suspension on all four
corners (e.g., 1987 – 1990 Reynard, Swift DB1) may use the following alternative tires. Note: This rule is intended to allow older
cars with the described suspension design to use the alternative tires. It is not to be exploited by modifying cars with push-rods or
pull-rods to meet the above requirements or by modifying either end of older cars to push- or pull-rod suspension to be eligible to
run the alternative tires. Cars that were homologated in 1989 or earlier with push- or pull-rod suspension on no more than two
corners may seek approval to run the alternative tire by utilizing the compliance process outlined in GCR section 8.1.4."

GT2 GT3 Turbo to GT2?

#39365 from Chris Edens · Rule change · TB 26-01 (2026-01 Fastrack)

Summary

cars addedGT2 Mazda BP engine 1839cc classified with 46mm turbo inlet restrictor, 2250 lbs minimum weight.

As printed in Fastrack

In GT2 Spec Lines, Engines - MAZDA, classify Engine Family BP as follows:
GT2 Engines - MAZDA
Engine
Family
Engine Type Bore x Stroke
(mm)
Disp.
(CC)

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Head Type Valves /

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

STU Request for Permission on Aftermarket Turbo Kit and Intake

#39529 from John Grim · Rule change · TB 26-01 (2026-01 Fastrack)

Summary

fasterSTU Mazda MZR (LF, L3, L5) Turbo classified; Jack Spania Racing 70 mm intake manifold and Fab9 Tuning bottom-mount turbo kit approved.

As printed in Fastrack

In STU Spec Lines, Table A: Alternate Vehicle and Engine Allowances, Mazda MZR (LF, L3, L5), change Notes as follows:
"Short blocks, heads, and intakes may be freely swapped within these engine designations. May use Goodwin Part # 61-
2510 or, Gato Performance Part #31972 or Jack Spania Racing 70 mm sheet-metal aluminum Intake manifold. Must use stock
throttle body or Acura part number 16400-PND-A17."
In STU Spec Lines, Table A: Alternate Vehicle and Engine Allowances, classify Mazda MZR (LF, L3, L5) Turbo as follows:
STU Maximum Displacement (cc's) Minimum Weight Notes
Mazda MZR (LF, L3,
L5) Turbo

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Varies Chart Short blocks, heads, and intakes may be freely
swapped within these engine designations. May
use Jack Spania Racing 70 mm sheet-metal
aluminum Intake manifold. Must use stock
throttle body or Acura part number 16400-PND-
A17. Fab9 Tuning bottom-mount turbo kit
approved with one of the STU approved Turbos.

GT2 Tech Bulletins for GT2 and GT2-ST

#39537 from Grand Touring Committee · Rule change · TB 26-01 (2026-01 Fastrack)

Summary

slower991.2 GT3 Cup throttle body restrictor increases from 65mm to 70mm; 997.2 loses 100 lbs to 2800; Corvette LS engines get larger restrictors across multiple displacements and model years; LS3 and LT1 weight reduced 100 lbs each to 3150.

As printed in Fastrack

In GT2 Spec Lines, GT2 Cars – Porsche, classify 992.1 GT3 Cup as follows:
GT2 Cars – Porsche
Model Year Body
Style Driveline Wheel Base Notes
992.1
GT3 Cup
(22-25) 2 Dr RWD 4.0L flat six. 3250lbs. w/60mm Throttle Body Restrictor (TBR).
Cars must be prepared in accordance with the appropriate

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model/year Porsche factory 911 GT3 Cup parts
catalog/service manual. Cars may not be altered in any way
except as authorized below. Drivers must have the correct
year manuals as they apply to their specific car in their
possession. Safety, drivers comfort, driver control and
instrumentation items may be modified per the GCR. Original
factory installed Matter/ IMV roll cages are allowed. The
stock unmodified fuel tank is allowed. Windshield clips must
be installed per GCR 9.3 Windshield Clips/Rear Window
Straps. All other SCCA safety standards apply. Tires per GCR
9.3 Tires. Lubricants, consumable fluids (brake fluid, coolant
etc.) and oil filters are open free. Factory (OEM manufacturer)
Lexan front windows allowed as delivered. ABS is allowed.
In GT2 Spec Lines, GT2 Cars – Porsche, change Notes as follows:
991.1 GT3 Cup: "3.8L flat six. 3000lbs. w/72mm Throttle Body Restrictor (TBR). Aftermarket header allowed."
991.2 GT3 Cup: "4.0L flat six. 3000lbs. w/65mm 70mm Throttle Body Restrictor (TBR)."
997.2 GT3 Cup: "3.8L flat six. 2900 2800 lbs. Aftermarket header allowed."
In GT2 Spec Lines, GT2 – ST, Chevy Corvette (-2013), change as follows:
5665:
Restrictor: "81 85mm flat plate"
Notes: "GM LS1, LS6. LS1/LS6 C6 Corvettes using the OEM C6 intake manifold and 90 mm throttle body must use a 78mm flat
plate restrictor. OEM 75mm throttle body and manifold do not require a restrictor. LS6 may reduce weight by 50 lbs. L S1/LS6
alternate intake manifold, DORMAN part # 615-900."
LS2 5967 Restrictor: "83 85mm "
L76 5967 Restrictor: "80 83mm flat plate"
LS3 6162 Restrictor: "80 83mm flat plate"
6162 GM LS3:
Weight: "3250 3150"
Restrictor: "74 80mm flat plate"
6162 GM LT1:
Weight: "3250 3150"
Restrictor: "74 77mm flat plate"
In GT2 Spec Lines, GT2 – ST, Chevy Corvette (14-19), change as follows:
5665:
Restrictor: "83 85mm flat plate"
Notes: "GM LS1, LS6. LS1/LS6 C6 Corvettes using the OEM C6 intake manifold and 90 mm throttle body must use a 78mm flat
plate restrictor. OEM 75mm throttle body and manifold do not require a restrictor. LS6 may reduce weight by 50 lbs. L S1/LS6
alternate intake manifold, DORMAN part # 615-900."
LS2 5967:
Weight: "3100 3000"
Restrictor: "83 85mm flat plate"
L76 5967 Restrictor: "80 83mm flat plate"
6162 Restrictor: "80 83mm flat plate"
6162 LS3:
Weight: "3200 3100"
Restrictor: "77 80mm flat plate"
6162 LT1:
Weight: "3200 3100"
Restrictor: "74 80mm flat plate"

GT2 Allow Larger Air Cooled Engines in Porsche 911 GT2

#39249 from Justin Erion · Rule change · TB 26-02 (2026-02 Fastrack)

Summary

fasterGT2 Porsche 911 SC gains option of 4.0L 4V engine at 2350 lbs or 4.0L 2V at 2275 lbs.

As printed in Fastrack

In GT Spec Lines, create GT Cars - PORSCHE and classify SC as follows:
GT Cars - PORSCHE
Model Years Body Style Drive- line Wheel- base
(in)
Notes
SC 1978 2 Dr. Rear engine/RWD 89.45 May use alternate engine bore.
4.0L 2V @2275 lbs. 4.0L 4V @ 2350 lbs.

GT2 Classify T1 BMW in GT2

#39408 from Jared Lendrum · Rule change · TB 26-02 (2026-02 Fastrack)

Summary

cars addedM3 E92 classified in GT2 with 3999cc V8, 35mm restrictor, 3300 lbs minimum weight.

As printed in Fastrack

In GT Spec Lines, classify M3 E92 in GT Cars - BMW as follows:
GT Cars - BMW
Model Years Body Style Drive-
line
Wheel-
base (in)
Notes
M3 E92 (08-13) 2 Dr. RWD 108.7 Cannot be built to any other rule set.

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In GT Spec Lines, classify M3 E92 in GT Engines - BMW - BMW as follows:
GT Engines - BMW
Engine
Family
Engine Type Bore x Stroke

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

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