This track has been raced on 4 configurations (The Circuit, 2.57 mi; 2.92 mi; 1.83 mi; 3.02 mi). Laps on different configurations are not comparable, so only events on the 2.57 mile layout are shown; switch above to see the others.
One session is left out because the timing does not look like full laps: Cal Club 2023 Qualifying #2.
One 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
S1 SF → IM1 0.65 mi
S2 IM1 → IM2 0.75 mi
S3 IM2 → SF 1.17 mi
Spd In → Out 0.03 mi
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
Car
Class
Drivers
Lap
Qual
Race
Trap
S1
S2
S3
BMW M3
T1
1
1:46.465Ian Barberi
1:46.465Ian Barberi
1:47.434Ian Barberi
114.9Ian Barberi
28.992Ian Barberi
30.811Ian Barberi
46.263Ian Barberi
BMW M4 GT4
T1
1
1:47.084Drew Delmonico
1:47.084Drew Delmonico
1:47.467Drew Delmonico
161.4Drew Delmonico
29.150Drew Delmonico
30.850Drew Delmonico
46.316Drew Delmonico
Mazda Miata
EP/STL
20
1:51.665Jared Korth
1:53.088Glen McCready
1:53.487Glen McCready
136.6Bryce Johnson
8.264Gavin Wardle
32.218Jared Korth
48.811Jared Korth
Mazda MX-5
EP/STL
8
1:51.665Jared Korth
1:53.088Glen McCready
1:53.487Glen McCready
136.6Bryce Johnson
8.264Gavin Wardle
32.218Jared Korth
48.811Jared Korth
Mazda Miata
EP/STL
11
1:52.034Joe Carr
1:54.963Nick Leverone
1:55.682Nick Leverone
133.4Wesley Mollno
30.815Jon Davies
32.405Joe Carr
49.197Wesley Mollno
Mazda MX-5 (2015)
STL
1
2:00.239Adrian Comstock
2:00.239Adrian Comstock
2:00.722Adrian Comstock
133.0Adrian Comstock
32.847Adrian Comstock
34.493Adrian Comstock
52.675Adrian Comstock
Mazda RX-8
STL
1
1:53.515David LeCren
2:09.464David LeCren
2:11.372David LeCren
121.0David LeCren
31.217David LeCren
32.486David LeCren
49.550David LeCren
Honda Civic Si
STL
1
1:56.438Jonathan Lugod
1:57.331Jonathan Lugod
1:56.438Jonathan Lugod
106.8Jonathan Lugod
31.787Jonathan Lugod
33.468Jonathan Lugod
50.873Jonathan Lugod
Mazda RX-7
EP
2
1:56.468Kurt Frietzsche
1:56.468Kurt Frietzsche
1:56.573Kurt Frietzsche
120.7Kurt Frietzsche
31.324Kurt Frietzsche
33.891Brandon Droese
50.204Kurt Frietzsche
Honda Prelude
STL
1
1:56.961Carl Young
1:57.917Carl Young
1:56.961Carl Young
104.5Carl Young
31.994Carl Young
33.745Carl Young
50.892Carl Young
Pontiac GTO
T1
1
1:59.123Ed Gless
1:59.760Ed Gless
1:59.123Ed Gless
120.7Ed Gless
32.383Ed Gless
34.587Ed Gless
51.370Ed Gless
Ford Mustang
T1
1
1:59.261Pratt Cole
1:59.261Pratt Cole
98.6Pratt Cole
32.624Pratt Cole
34.661Pratt Cole
51.577Pratt Cole
BMW E30
EP
1
2:00.712Sean Lovett
2:00.712Sean Lovett
2:01.864Sean Lovett
127.6Sean Lovett
32.761Sean Lovett
34.806Sean Lovett
53.058Sean Lovett
Porsche Boxster
EP
1
2:01.940William Robinson
2:01.940William Robinson
2:02.887William Robinson
130.6William Robinson
32.969William Robinson
35.257William Robinson
53.408William Robinson
Acura integra
STL
1
2:24.310Jack McEachern
2:24.310Jack McEachern
2:24.550Jack McEachern
77.6Jack McEachern
38.960Jack McEachern
41.141Jack McEachern
1:02.410Jack McEachern
The best any driver of each car managed across the selected events, with who set it. Spellings and model years of the same car are grouped; click a row marked ▸ to see each version. Grouping is worked out from the names, so tell us if two cars are wrongly merged or split.
Rule changes between these events
Cal Club 2023 → Cal Club 2024 2023-02-24 to 2024-02-23
T1 Sequential Gearbox Limitations in T1
#33691 from David Mead · Rule change · TB 23-03 (2023-03 Fastrack)
neutralT1 cars with aftermarket sequential transmissions get 10-inch max bellhousing; non-sequential cars gain 100 lbs weight break.
In GCR, Section 9.1.9.1.I.4., change as follows: "Aftermarket sequential transmissions are permitted. Cars with aftermarket sequential shift transmissions shall utilize a 1:1 (or greater/overdriven) ratio in top gear. Transmission location must be OEM. Maximum bellhousing length is 10 inches. Cars that don’t use an aftermarket sequential transmission may decrease their competition weight by 100 lbs."
In T1, GCR Section 9.1.9.1.A., remove in its entirety. In T1 Spec Lines, remove in its entirety.
EP Investigate Parity of Z3
#33343 from Tim Schreyer · Rule change · TB 23-01 (2023-01 Fastrack)
slowerEP BMW Z3 2.5L intake restrictor reduced from 58mm to 56mm flat plate.
Effective 4/1/2023 In EP Spec Line BMW Z3 2.5L, change Notes as follows: "58 56mm Flat Plate Intake Restrictor is required with both stock or alternate throttle body."
T1 Clarification for Camaro Gen5 2010-2015
#33739 from Clark Nunes · Rule change · TB 23-04 (2023-04 Fastrack)
neutralT1 GT4 weights clarified for nine cars, ranging from 3200 lbs Porsche 718 Cayman to 3575 lbs Aston Martin.
RM 23-04 – Touring 1 weights dated 3/21/2023 As an E&O to the February Fastrack, in T1-GT4 leave weights as follows: Aston Martin Vantage AMR GT4: 3575 Audi R8 GT4: 3550 BMW M4 GT4: 3500 Ford Mustang GT4: 3550 Maclaren 570S GT4: 3450 Mercedes AMG GT4: 3450
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Porsche 718 Cayman GT4 CS MR: 3200 Porsche 718 GT4 RS Clubsport: 3450 Toyota Supra GR GT4: 3350
T1 Touring 1 Tire Sizes
#34191 from Club Racing Board · Rule change · TB 23-05 (2023-05 Fastrack)
fasterT1-GT4 McLaren 570S and Mercedes AMG GT4 front tires widen to 315 mm.
neutralSTL ITA/ITS RX7 and 1985+ ITA/ITS/ITB/ITC vehicles clarified to conform to section 9.1.4.2 tire specifications.
In STL Spec Lines, Table B: Alternate Vehicle and Engine Allowances, change Notes as follows: ITA-spec and ITS-spec RX7: "Must completely conform to ITCS specifications. Tires must conform to 9.1.4, Tires & Wheels. Tires must also conform to 9.1.4.2.Tires." ITS, ITA, ITB, or ITC vehicles (1985- ): "Must completely conform to ITCS specifications. Tires must conform to 9.1.4, Tires & Wheels. Tires must also conform to 9.1.4.2.Tires."
T1 Gen 5 Camaro Engine
#33875 from Matt Spicuzzi · Rule change · TB 23-06 (2023-07 Fastrack)
neutralT1 Chevrolet Camaro Gen 5 LS7 gets two spec lines: 1131 with 70mm restrictor, 1136 with 53mm restrictor, both 3450 lbs minimum.
In T1-NEW Spec Lines, Chevrolet Camaro Gen 5 (10-15) Including SS, Z28, classify Spec Line Number 1131 and 1136 as follows:
A specification table follows in the original; it is not shown here.
T1 Inquiry to letter #33682
#34071 from Andrew Aquilante · Rule change · TB 23-06 (2023-07 Fastrack)
slowerT1 Chevrolet Camaro Gen 5, Corvette C5 and C6: engine resleeve restricted to stock parameters only, no longer LS3 bore/stroke.
In T1 NEW Spec Lines, Chevrolet Camaro Gen 5 (10-15) Including SS, Z28, change Engine Notes as follows: 1130: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement." 1135: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement.May resleeve to stock parameters for engine repair or replacement." In T1 NEW Spec Lines, Chevrolet Corvette C5 (‘97-’04) – Includes: Z06, Coupe, Convertible, change Engine Notes as follows: 1132: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement."
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1134: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement." 1136: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement." 1138: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement." In T1 NEW Spec Lines, Chevrolet Corvette C6 (05-13) - Includes Z51, GrandSport, Z06, Z06 Carbon, change Engine Notes as follows: 1150: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement." 1160: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement." 1170: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement." 1180: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement." 1190: "May resleeve any LS block to LS3 bore/ stroke for Engine replacement. May resleeve to stock parameters for engine repair or replacement."
T1 Viper Cleanup
#34107 from Scotty B White · Rule change · TB 23-06 (2023-05 Fastrack)
fasterT1 Dodge Viper ACR/ACR-X restrictor increases from 50mm to 60mm flat plate.
In T1 NEW Spec Lines, Dodge Viper ACR/ACR-X Spec Line 1360, change Required Restrictor as follows: "50mm 60mm flat plate"
T1 Viper 8300 OEM FPR Size
#34268 from Scotty B White · Rule change · TB 23-06 (2023-05 Fastrack)
unclearT1 Dodge Viper ACR/ACR-X: Spec Line 1370 restrictor increases to 55mm, Line 1390 decreases to 55mm.
In T1 NEW Spec Lines, Dodge Viper ACR/ACR-X Spec Line 1370, change Required Restrictor as follows: "(2) 47mm 55mm flat plates" In T1 NEW Spec Lines, Dodge Viper ACR/ACR-X Spec Line 1390, change Required Restrictor as follows: "(2) 60mm 55mm flat plates"
EP Correct Intake Valve Size on 1500cc Midget/Spitfire
#34419 from Production Committee · Rule change · TB 23-06 (2023-05 Fastrack)
neutralFP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44).
In FP Spec Lines, Austin-Healey Sprite Mk. I, II,III, IV MG Midget Mk I,II, III, IV & 1500, change Intake Valve Size as follows: "(I) 36.65.3/(1.44)" In FP Spec Lines, Triumph Spitfire Mk. IV & 1500, change Intake Valve Size as follows: "(I) 36.65.5/(1.440)" In HP Spec Lines, Triumph Spitfire 1500, change Intake Valve Size as follows: "(I) 36.65.5/(1.440)" In HP Spec Lines, Triumph Spitfire Mk. III & IV 1500, change Intake Valve Size as follows: "(I) 36.65.5/(1.440)"
T1 Ford Mustang S197 (05-14) Clarification
#34450 from Club Racing Board · Rule change · TB 23-06 (2023-05 Fastrack)
neutralT1 Ford Mustang S197 05-14 now requires OEM 8.8 differential housing.
In T1-NEW Spec lines, Ford Mustang S197 (05-14) Includes GT, Boss302, 302S, 302R, FR500C, FR500S, change Notes as follows: "OEM 8.8 Differential Housing"
T1 C5 Approved Aero That Was Mistakenly Deleted
#34374 from Joe Aquilante · Rule change · TB 23-08 (2023-08 Fastrack)
fasterT1 Corvette C5 gains approved aero parts: carbon rear spoiler, vented front splitter, side skirts, with 50 lb weight reduction allowed.
In T1 NEW Spec Lines, Chevrolet Corvette C5 (‘97-’04) – Includes: Z06, Coupe, Convertible, Spec Lines 1132-1138, add to Notes as follows: "Any option of OEM Bodywork parts may be used as basis for aero measurements. Rear spoiler max 5” Above bumper allowed. +50lbs. The following parts are permitted, with a 50lb decrease from base weight, in lieu of the aero options permitted in 9.1.9.1.B: (C7Carbon Rear- Spoiler CCC5 EX- RSB-GB, Vented Front Splitter CCC5-FS-GB, Side Skirts CCC5 SS-GB.)"
T1 Why no Camaro?
#34421 from Scotty B White · Rule change · TB 23-08 (2023-05 Fastrack)
neutralChevrolet Camaro GT4-R classified in T1 GT4 Spec Line 4035, minimum weight 3375 lbs, 315 max tire, 63mm restrictor, ineligible for Runoffs.
In T1 GT4 Spec Lines, classify Chevrolet Camaro GT4-R as follows:
A specification table follows in the original; it is not shown here.
T1 Request to Remove Expiration from T1 spec lines #1350 & #1370
#34470 from Scotty B White · Rule change · TB 23-08 (2023-05 Fastrack)
neutralT1 Dodge Viper ACR / SRT RT-10 and ACR/ACR-X spec lines 1350 and 1370 remove 12/23 expiration.
In T1 NEW Spec Lines, Dodge Viper ACR / SRT RT-10, change Spec Line Number as follows: "1350 *Spec line Expires 12/23*" In T1 NEW Spec Lines, Dodge Viper ACR/ACR-X, change Spec Line Number as follows: "1370 *Spec line Expires 12/23*"
neutralT1 GT4 BMW M4 Spec Line Number changed from 4050 to 4030.
In T1 GT4 Spec Lines, BMW M4, change Spec Line Number as follows: "4050 4030"
EP Hub Note Clean Up In EP TR8 Spec Line
#34649 from Jeff young · Rule change · TB 23-09 (2023-09 Fastrack)
neutralEP Triumph TR8 78-81 removes alternate front hub allowance note; stock hubs now required.
In the EP Spec Lines, Triumph TR8 (78-81), remove the following wording from Notes: "Alternate front hubs are allowed provided they are of the same external dimensions as stock and weigh no less than the stock hubs."
EP Triumph GT6 Adjustments
#34662 from ANTHONY PARKER · Rule change · TB 23-09 (2023-09 Fastrack)
unclearEP Triumph GT6 carburetors change from SU or Stromberg to 1.5" Auto-type.
In EP Spec Lines, Triumph GT6, change Carburetor. No. & Type as follows: "(2) 1.5” SU or Stromberg Auto-type carburetor(s)"
EP Triumph GT6 Adjustments: Brakes
#34663 from ANTHONY PARKER · Rule change · TB 23-09 (2023-09 Fastrack)
neutralEP Triumph GT6 brakes may now use TR-6 standard or alternate calipers and discs.
In EP Spec Lines, Triumph GT6, add the following to Brakes Alt.: mm/(in.): "(F) Calipers & discs from TR-6 (std. or alt)"
T1 New T1 add spec line for C5 corvette LS2 engines (Copy from C6)
#33764 from Craig Anderson · Rule change · TB 23-12 (2023-09 Fastrack)
neutralT1 Chevrolet Corvette C5 LS2 added with 6000cc displacement, 3300 lbs minimum weight, 72mm flat plate restrictor.
In T1 Spec Lines, classify Chevrolet Corvette C5 (‘97-’04) – Includes: Z06, Coupe, Convertible as follows:
A specification table follows in the original; it is not shown here.
T1 2004 - 2006 Pontiac GTO Re-Integration Back Into T1
#34403 from Ed Gless · Rule change · TB 23-12 (2023-12 Fastrack)
neutralPontiac GTO 2006-2009 re-integrated into T1 with LS2 at 3400 lbs, 72mm restrictor, and LS3 at 3500 lbs, 61mm restrictor.
In T1 Spec Lines, classify Pontiac GTO 2006-2009 as follows:
A specification table follows in the original; it is not shown here.
Applies to Pontiac GTO on this page: Ed Gless
T1 Request to Classify Porsche 997-1 GT3 Cup
#34561 from Scotty B White · Rule change · TB 23-12 (2023-12 Fastrack)
neutralT1 Porsche 997-1 GT3 Cup added at spec line 4210, minimum weight 3050 lbs.
In T1 Spec Lines, delete the Porsche 996 GT3 Cup car from the standard spec lines and classify "Homologated car" section as follows: T1 – Homologated Cars
A specification table follows in the original; it is not shown here.
T1 C7 Corvette Rule Change Request
#34897 from Heath Karl · Rule change · TB 23-12 (2023-09 Fastrack)
neutralT1 Chevrolet Corvette C7 (14-19) including Z51, Grandsport newly classified as homologated car.
In T1 Spec Lines, classify Chevrolet Corvette C7 (14 - 19) - Includes Z51, Grandsport as follows: T1 – Homologated Cars
A specification table follows in the original; it is not shown here.
EP Porsche 944/924S Rule Change Request
#35002 from Adam Achepohl · Rule change · TB 23-12 (2023-12 Fastrack)
neutralEP Porsche 944/924S combines 2.5L and 2.7L variants with new weights: 2250–2415 lbs depending on engine and year.
In EP Spec Lines, delete the Porsche 944/924S 2.5L (2V) (83-88) spec line entirely, and create a new spec line for Porsche 944/924S 2.5L(2V) 2.7L(2V) (83-89) as follows:
A specification table follows in the original; it is not shown here.
EP Triumph GT6 Adjustments
#35054 from ANTHONY PARKER · Rule change · TB 23-12 (2023-12 Fastrack)
fasterEP Triumph GT6 minimum weight reduced to 1800 lbs.
In EP Spec Lines, Triumph GT6, change weight as follows: "1830 1800"
T1 Camaro Gen 5 Weight Reduction Due to Competitive Disadvantage
#35092 from Clark Nunes · Rule change · TB 23-12 (2023-09 Fastrack)
fasterT1 Gen 5 Camaro minimum weight drops 75 lbs to 3475; restrictor increases 70mm to 75mm.
In T1 Spec Lines, Gen 5 Camaro, change as follows: Spec Line 1130 - Minimum Weight "3550 3475" Spec Line 1135 - Minimum Weight "3550 3475" Restrictor Required "70mm 75mm-Flat Plate"
unclearT1-GT4 batch adjustments: five cars lighter, two heavier, restrictors and ECU maps changed, five models now eligible for Runoffs.
In GCR, Section 9.1.9.1.A.T., change as follows: "Tires- Tires must conform to GCR section 9.3.TIRES and als o must conform to spec line requirements. DOT approved tires are permitted. Slicks conforming to the spec line are permitted." In Touring 1 - Homologated Cars Spec Lines, 4100- BMW M2 ClubSport Racing, change Must Conform To as follows: "Tires conforming to SRO TCX rules allowed. Must meet factory specs." In Touring 1 - Homologated Cars Spec Lines, 4120- Ford Mustang FP350S 2017, change as follows: Must Conform To: "Tires conforming to Trans Am SGT tire rules allowed Must meet factory specs." Chassis Notes: "VIN not required. Additional permitted allowances: DOT tires required. Other consumables are open, alternate
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driveshaft permitted, aftermarket wheels and fuel cell per Touring category rules permitted. Shocks conforming to T1 rules permitted. Alternative rear toe links permitted." In T1-GT4 Spec Lines, change Chassis Notes as follows: Aston Martin Vantage AMR GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)** Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." Audi R8 GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." BMW M4 GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." Chevrolet Camaro GT4-R: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." Ford Mustang GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." Maclaren 570S GT4: "Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." Mercedes AMG GT4: "Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." Porsche 718 Cayman GT4 CS MR: "Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." Porsche 718 GT4 RS Club-sport: "Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." Toyota Supra GR GT4: "**NOT YET ELLIGIBLE FOR RUNOFFS COMPETITION (Q.2)**Slick tires conforming to IMSA GT4 or SRO GT4 specs are permitted." In T1-GT4 Spec Lines, change as follows: Aston Martin Vantage AMR GT4: Weight: “3575 3490” Performance Control: “SRO power level ECU Map 3 IMSA Map id 11” Chevrolet Camaro GT4-R: Weight: “3375 3435” Performance Control: “63 62mm” Ford Mustang GT4: Weight: “3550 3535” Performance Control: “63 71mm SRO compliant restrictor IMSA ECU Cal” Maclaren 570S GT4: Weight: “3450 3250” Performance Control: “SRO 2019 BOP ECU map SRO Rest 1” Mercedes AMG GT4: Weight: “3450 3470” Performance Control: “Power level 2 map 5” Porsche 718 Cayman GT4 CS MR: Weight: “3200 3250” Performance Control: “54 53.7mm” Toyota Supra GR GT4: Weight: “3350 3315”
STL Alternate Carburetor Request for 79-85 RX7 12a
#35181 from Dan Sheppard · Rule change · TB 24-01 (2024-01 Fastrack)
unclearSTL Mazda RX-7 12A (79-85) now allows auto-type 2 bbl with 42mm choke(s) on dual-y manifold as alternate to stock Nikki 4 bbl.
In STL Table B: Alternate Vehicle and Engine Allowances, Mazda RX-7 12A (79-85), change Notes as follows: "Street Porting of the engine only. Bridge porting, peripheral porting, and eyelash porting are prohibited. Contact SCCA National Office for details of Street porting. Stock Nikki 4 bbl carburetor on a stock manifold only. or auto-type 2 bbl w/42mm choke(s) on a “dual-y” manifold. Allow the standard removal of emissions related components, and allow air and fuel jets to be corrected. Modification of the water jacket in the area of the spark plug for cooling purposes is permitted."
In EP spec line, Triumph GT6, make the following change in the Notes section: "Two (2) 1.75” auto-type carburetors @ 1970 40 lbs. Three (3) Weber 40 DCOE on IR manifold with 28mm chokes @ 1990 lbs. Laycock overdrive, May use 5 speed gearbox w/o overdrive. Three (3) Weber 40mm DCOE w/28mm venturi on individual runner manifold @ 2020 lb."
EP Honda S2000 throttle body
#35272 from Aaron Johnson · Rule change · TB 24-01 (2024-01 Fastrack)
fasterEP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm.
In EP spec line, Honda S2000, make the following changes to its spec line: Fuel Injected Equipped Throttle Body Inside Diameter: "62 64" Notes: "Comp. Ratio limited to 12.0:1. Valve lift limited to .500”. An adaptor plate can be used to mount the 62mm throttle body from '00-05 to the '06-09 intake manifold. The adaptor plate can be no more than 1.25" thick, and its bore must not exceed the "Fuel Injected Equipped Throttle Body Inside Diameter" maximum spec of 64mm."
EP Correction within Triumph TR8 Spec Line
#35315 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)
neutralEP Triumph TR8 dry sump allowance moved from carburetor line to notes section.
In EP spec line, Triumph TR8 (78-81), move the "Dry sump allowed" wording to the appropriate location as follows: Carburetor. No. & Type: “Zenith Stromberg carbs or fuel injection. Dry sump is allowed.” Notes: “Comp. Ratio limited to 12.0:1, Valve lift limited to .500”. Dry sump is allowed.”
EP Correction to EP 924S/944 Spec Line
#35317 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)
neutralEP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs.
In EP spec line, Porsche 944/924S 2.5L (2V) / 2.7L (2V) (83-89), change Weight as follows:
A specification table follows in the original; it is not shown here.
STL ST Electric-Assisted Steering Systems
#35066 from Jose Osiris Pena · Rule change · TB 24-02 (2024-01 Fastrack)
neutralSTL and STU power steering rules clarified to permit electric-assisted and hydraulic-assisted steering systems.
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"
STL BOP Adjustments
#35112 from Super Touring Committee · Rule change · TB 24-02 (2024-01 Fastrack)
fasterSTL Acura/Honda B-series and Mazda MZR restrictors reduced 2mm; minimum weights down 25–75 lbs for 1900–2000cc engines.
In GCR, 9.1.4.H.1., change as follows: "Minimum weights for cars with normally aspirated piston engines will be determined by 1.35 lbs/cc displacement for the installed engine (see the following table). Displacement is the factory displacement for the installed engine. For the purpose of weight assignment, engine displacement will be rounded to the nearest 50cc (e.g., 2176cc = 2200cc and 2175cc = 2150cc)." In GCR, 9.1.4.H.1., change Minimum Weight on Chart as follows: Factory Engine Displacement 1900: "Effective 3-1-24: 2565 2540" Factory Engine Displacement 1950: "Effective 3-1-24: 2633 2583"
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Factory Engine Displacement 2000: "Effective 3-1-24: 2700 2625" In GCR, 9.1.4.H.3., change as follows: "Front wheel drive cars with a strut type front suspension may reduce their minimum weight by 2.5 percent. Effective 3- 1-24: Front wheel drive cars with 95" or less wheelbase must add 1.25% to their minimum weight." In STL Spec Lines, change Notes as follows: Acura/Honda B16: "Effective 3-1-24: 53 51mm" Acura/Honda B17: "Effective 3-1-24: 53 51mm" Acura/Honda B18C1: "Effective 3-1-24: 53 51mm" Acura/Honda B18C (JDM Type R), B18C5 (USDM Type R), B18C6 (UK and Euro Type R), B18C7 (Australia Type R): "Effective 3-1-24:52 50mm" Mazda MZR: "Effective 3-1-24: 52 50mm"
neutralT1 NEW class removes 23 spec lines including Acura NSX, Ferrari, Porsche 996, Nissan Z cars, and others; Porsche 997 spec line 1680 expiration removed.
In GCR Contents, change as follows: "9.1.9.1 TOURING (T1) CATEGORY NEW T1 NEW" In GCR, Section 9.1.9.1.Touring (T1) NEW Category Specifications, change as follows: "9.1.9.1.Touring (T1) NEW Category Specifications" In T1 NEW Spec Lines, change as follows: "9.1.9.1.A T1 NEW Spec Lines" "T1 NEW"
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In T1 NEW Spec Lines, delete the following Spec Lines in their entirety: "Acura NSX (Spec Line 1000) Acura NSX Turbo (Spec Line 1010) Acura NSX Turbo World Challenge (Spec Line 1020) Audi TTRS (GTS 2011 Spec) (Spec Line 1040) Dodge Viper ACR/ACR-X (Spec Line 1360) Ferrari 360 (Spec Line 1400) Ferrari 430 (Spec Line 1410) Ferrari 430 Challenge (Spec Line 1420) Mazda MX-5 (06-15) (Spec Line 1520 and 1530) Mazda RX-7 (Spec Line 1540) Nissan GTR (Spec Line 1550) Nissan 350/370Z (Spec Line 1560) Nissan 370Z Supercharged (Spec Line 1570) Nissan 350Z (Spec Line 1580) Nissan 350Z/370Z (Spec Line 1590) Porsche Cayman/S/GTS (05-15) (Spec Line 1600, 1610 and 1620) Porsche Cayman GTS (2011) (Spec Line 1630) Porsche 928 S4 Porsche 928 GTS-R (Spec Line 1640) Porsche 996 (Spec Line 1650) Porsche 996 TT OEM (Spec Line 1660) Subaru WRX, WRX STI (05-2020) (Spec Line 1700) Toyota Celica All-Trac (Spec Line 1710) Toyota Supra MK4 (Spec Line 1720)" In T1 NEW Spec Lines, Porsche 997, change Spec Line Number as follows: "1680 *Spec line Expires 12/23*"
In HP Spec Lines, delete the following redundant spec lines in their entirety: Spec line #10 - VW Rabbit Cabriolet 1780 Spec line #3 - VW Scirocco 1588 Spec line #4 - VW Scirocco 1780 (8-valve) (83-88) Spec line #5 - VW Scirocco 1588
neutralNissan 300ZX 84-89 classified to EP at 2550 lbs minimum, 2960cc 6-cyl SOHC, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit.
In EP Spec Lines, classify Nissan 300ZX (84-89), as follows:
A specification table follows in the original; it is not shown here.
EP RX7 1993 and Up Request In EP Spec Lines, classify
#36031 from Edward Zabinski · Rule change · TB 24-06 (2024-06 Fastrack)
neutralMazda RX-7 92-97 newly classified EP Prep Level 2 at 2200–2310 lbs with 13B 6-port rotary engine.
Mazda RX-7 (92-97) as follows:
A specification table follows in the original; it is not shown here.
EP Clean-up Multiple EP RX-8 Spec Lines In EP
#36156 from Production Committee · Rule change · TB 24-06 (2024-06 Fastrack)
neutralEP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains.
Spec Lines, make the following changes to the two Mazda RX-8 spec lines. Remove spec line entirely: Mazda RX-8 (04-11) Remove the wording "alternate": Mazda RX-8 (04-11)(alternate) Spec Mazda (SM/SMX) None.
fasterHP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1.
In HP Spec Lines, Austin-Healey Sprite MkI, II, III, IV MG Midget (ALL) - Level 2 - 1275cc, change Notes as follows: "(Effective 11/1/2024) Compression ratio limited to 11 12.0:1" In HP Spec Lines, Austin-Healey Sprite MkI, II, III, IV MG Midget (ALL) - Level 2 - 1098cc, change Notes as follows: "(Effective 11/1/2024) Compression ratio limited to 11 12.0:1"
EP NA Miata Track Width Correction
#36902 from Production Committee · Rule change · TB 24-11 (2024-11 Fastrack)
neutralEP Mazda Miata front and rear track widths increased to 1516/1534 mm (59.7/60.4 in.) across all generations.
neutralBMW M4 GT4 (G82) added to T1 GT4 at 3525 lbs minimum weight with Red power stick control.
In T1 GT4 Spec Lines, SL#4030, change as follows: Model: "BMW M4 GT4 (F82)" Performance Control: "Gold power stick Red power stick" In T1 GT4 Spec Lines, classify BMW M4 GT4 (G82) as follows:
A specification table follows in the original; it is not shown here.
T1 Alt. Clutch Allowance
#36606 from Hugh Stewart · Rule change · TB 24-12 (2024-12 Fastrack)
neutralT1 Spec Lines now permits 5.5 inch clutch in Engine Notes.
In T1 Spec Lines, SL# 1050, change add to Engine Notes the following: "5.5 inch clutch permitted."
T1 BOP Changes Need Updates
#36667 from Joe Rainey · Rule change · TB 24-12 (2024-12 Fastrack)
fasterT1 GT4 Spec Line 4020 restrictor opens from 44mm to 45mm, minimum weight drops to 3400 lbs.
In T1 GT4 Spec Lines, Spec Line 4020, change as follows: Performance Control: Power level 2020, 44mm 45mm SRO compliant restrictor" Min. Weight with driver (LBS): "3550 3400"
EP Triumph GT6 Adjustments
#37112 from Anthony Parker · Rule change · TB 24-12 (2024-12 Fastrack)
slowerEP Triumph GT6 switches to three Weber 40 DCOE carbs with 28mm chokes, weight rises 50 lbs to 1990.
In EP Spec Lines, make the following changes in the "Triumph GT6" spec line: Carburetor No. & Type: (2): "1.5” 1.75" Auto-type carburetor(s)" Notes: "Two (2) 1.75” auto-type carburetors @ 1940 lbs. Three (3) Weber 40 DCOE on IR manifold with 28mm chokes @ 1990 lbs. Laycock overdrive, May use 5 speed gearbox w/o overdrive."
T1 Request Ford Performance Darkhorse R in T1
#37136 from Christopher Childs · Rule change · TB 24-12 (2024-12 Fastrack)
neutralMustang Darkhorse R added to T1 homologated cars at 3,250 lbs minimum with 305/315 tires, ineligible for Runoffs until 3 Super Tour events.
In T1-Homologated Cars Spec Line, classify Mustang Darkhorse R (Mustang Challenge) as follows: T1 – Homologated Cars
A specification table follows in the original; it is not shown here.
STL Request to Remove Miata Hubs from General category
#37138 from Christopher Childs · Rule change · TB 24-12 (2024-12 Fastrack)
neutralSTL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval.
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."
T1 Car Mods for T1 Corvette under line item 1150
#37173 from Thomas Napolitano · Rule change · TB 24-12 (2024-12 Fastrack)
neutralT1 Corvette may roll or flatten wheel opening lips for tire clearance; plastic fenders may remove lips if edge thickness matches basic material.
In GCR, Section 9.1.9.1.A.2,, add the following: "It is permitted to roll under or flatten any interior lip on the wheel opening for tire clearance. Cars with plastic/composite fenders may remove any interior wheel opening lip, but the resulting material edge shall be no thinner than the basic fender material thickness. Non-metallic inner fender liners may be removed. Vents may be added to fenders."
T1 Increased Bore Throttle Bodies for E46 M3 S54 Engine
#37273 from Mark Pfeffer · Rule change · TB 24-12 (2024-12 Fastrack)
fasterT1 E46 M3 S54 can now use Dinan Throttle Body #D760-3400 on 3.250L engine.
In T1 Spec Lines, E46 M3 Spec Line # 1050, add to Engine Notes the following: "Dinan Throttle Body #D760-3400 allowed on the 3.250L."
EP Request to Reduce Weight of BMW 325i/is E30 (84-91) Spec Line
#37119 from Tim Schreyer · Rule change · TB 25-01 (2025-01 Fastrack)
fasterEP BMW 325i/is E30 (84-91) weight reduced 50–52 lbs across three spec lines to 2150, 2204, 2258.
In EP SPEC LINES, BMW 325i/is (E30) (84-91), change Weight as follows: "2200 2150 *2255 2204 **2310 2258"
T1 T1 Parity Compared to GT4
#37170 from Tony Ave · Rule change · TB 25-02 (2025-02 Fastrack)
slowerT1 Mustang gains 125 lbs to 3600, restrictor shrinks 65mm to 60mm. Corvette gains 50 lbs to 3500, restrictor shrinks 70mm to 67mm. BMW deleted.
In T1 Spec Lines, change Weight and Restrictor Required as follows: Mustang - Spec Line 1430 Weight: "3475 3600" Restrictor Required: "65mm 60mm - FPR" Corvette Spec Line 1190 Weight: "3450 3500" Restrictor Required: "70mm 67mm - Flat Plate" In T1 Spec Lines, delete Spec Line BMW # 1190 in its entirety.
T1 Clarification of Request Approval #37273
#37399 from Mark Pfeffer · Rule change · TB 25-02 (2025-02 Fastrack)
unclearT1 E46 M3 Spec Line 1050 allows VAC Motorsports throttle body VAC-TB-S54 on 3.250L engine instead of Dinan.
In T1 Spec Lines, E46 M3 Spec Line # 1050, change Engine Notes as follows: "Dinan Throttle Body #D760-3400 VAC Motorsports #VAC-TB-S54 allowed on the 3.250L."
unclearT1 Mustang Spec 1430 restrictor opens 60mm to 65mm; Spec 1460 weight rises to 3500 lbs, restrictor 70mm; Corvette 1190 restrictor opens 67mm to 70mm; BMW 1090 restrictor narrows 40mm to 35mm; BMW 1100 weight rises to 3350 lbs.
In T1 Spec Lines, change Weight, Restrictor Required and/or Notes as follows: Mustang - Spec Line 1430: Restrictor Required: "60mm 65mm - FPR" Mustang - Spec Line 1460: Weight: "3425 3500" Restrictor Required: "70mm - FPR" Corvette Spec Line 1190: Restrictor Required: "67mm 70mm - Flat Plate"
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BMW - Spec Line 1090: Required Restrictor: "(2) X 40mm 35mm diameter hole inlet restrictor plate required" Chassis Notes: "This spec line is set to expire 12/31/25." BMW - Spec Line 1100: Minimum Weight: "3150 3350”
EP Request for Classification of Chevrolet Spark
#37755 from Kristian Smith · Rule change · TB 25-04 (2025-04 Fastrack)
neutralChevrolet Spark 16-22 classified HP Pre at 1850 lbs minimum weight, fuel injected, 1399 cc.
In HP Spec Lines, classify the Chevrolet Spark (16-22):
A specification table follows in the original; it is not shown here.
EP Request to Lower Ford Festiva Minimum Weight to 1600 LBS
fasterHP Ford Festiva 88-93 minimum weight drops to 1600 lbs, variants to 1640 and 1680 lbs; compression ratio raised to 11.0:1.
In HP Spec Lines "Ford Festiva (88-93)" change as follows: Weight: "1700 1600 *1743 1640 **1785 1680" Notes: "Compression ratio limited to 10.5 11.0:1. Valve lift limited to .450”."
neutralCadillac CT4-V Blackwing added to T1 Spec Line 1115, 3564cc, 3750 lbs minimum weight.
In T1 Spec Lines, classify Cadillac CT4-V Blackwing as follows:
A specification table follows in the original; it is not shown here.
T1 Acceptance of Porsche 981 GT4 Clubsport into T1
#36664 from John Brown · Rule change · TB 25-05 (2025-05 Fastrack)
neutralPorsche 981 GT4 Clubsport added to T1 as spec line 4085, minimum weight 3100 lbs with driver.
In T1-GT4 Spec Lines, classify Porsche 981 GT4 Clubsport as follows:
A specification table follows in the original; it is not shown here.
T1 Request to Restore T1 Honda S2000 to Proper Weights
#37644 from David Mead · Rule change · TB 25-05 (2025-05 Fastrack)
fasterT1 Honda S2000 minimum weight reduced from 2950 lbs to 2900 lbs.
In T1 Spec Lines, Honda S2000, Spec Line 1530, change as follows: Minimum Weight: "2950 2900" Chassis Notes: "This spec line is set to expire as of 12/31/2025 if not represented in Majors competition in 2025."
unclearSTL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1 instead of 2500 lbs; spec components removed, only alternative tires allowed.
In STL Spec Lines, Table B, Mazda Spec MX5 Challenge, change as follows: Minimum Weight: "2500 See 9.1.7.1." Notes: "Mazda MX5 Challenge car must utilize the following components: Roush CNC cylinder head 0000-01-5300,Mahle standard or +0.005 0000-01-5310, OEM camshaft, 11:1 compression ratio, header 0000-06-5407-NC, exhaust 0000-06-5427-NC, cold air intake 0000- 06-5150-KT, ECU flash 0000-01-5379, Pagid front brake pads 0000-03-5104-SP or endurance pads 0000-03- 5104-EN, Pagid rear brake pads 0000-03-5114-SP or endurance pads 0000-03-5114-EN, Penske front shock 0000-04-5291-SA, Penske rear shock 0000-04-5292-SA, Penske rear mount kit 0000-04-5358, Front mount kit 0000-04-5359, Front offset bushing 0000-04-5407-NC, Eibach front springs 0000-04-9700-08, Eibach rear springs 0000-04-9400-07, Eibach helper springs 0000-04-
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9926, Eibach front sway bar 0000-04-5306-FT, Eibach rear sway bar 0000-04-5306-RR, Interior finish panels 0000-07-5822, C&R radiator/oil cooler assembly 0000-01-5504-CR, Oil cooler adapter and lines 0000-01-5511-KT, ACT clutch 0000-02-5004-G6, wheels 17x8 #0000-04-5706-GM, # 0000- 04-5706-SL, and Toyo RR 235-40-17 dry, Toyo RA1 235-40-17 wet. Alternative tires on 17x7 wheels per STL rules. No other Super Touring modifications or allowances permitted except as noted in this spec line. Must conform completely to GCR 9.1.7.1, except alternative tires (only) per STL regs allowed."
Applies to Mazda Miata on this page: Jared Korth, Ricardo Arruda, Gavin Wardle, Ryan Gutile, Bryce Johnson, Andy Chittum, Adrian Comstock
T1 DCT Transmission in E46
#37964 from Matt Spicuzzi · Rule change · TB 25-05 (2025-05 Fastrack)
neutralT1 BMW E46 M3 permits BMW #GS7D36SG aftermarket sequential transmission in SL# 1060 and 1070.
In T1 Spec Lines, BMW E46 M3, add to Chassis Notes the following: SL# 1060: "BMW #GS7D36SG transmission permitted as an aftermarket sequential option." SL# 1070: "BMW #GS7D36SG transmission permitted as an aftermarket sequential option."
Applies to BMW M3 on this page: Ian Barberi
T1 Reduce E92 M3 Minimum Weight to 3050
#38092 from Shane Brown · Rule change · TB 25-05 (2025-05 Fastrack)
fasterT1 BMW M3 E92 minimum weight reduced to 3300 lbs.
In T1 Spec Lines, BMW M3 E92 (08-13), Spec Line 1100, change Min. Weight as follows: "3350 3300"
fasterT1 Mustang Darkhorse R gets 315 front and rear tyres, loses 500 lbs minimum weight to 3600.
In T1 Spec Lines, Mustang Darkhorse R (Mustang Challenge) Spec Line- 4119, change as follows: Tire size: "305 315 (f) 315(r)" Performance Control: "TBD" Min. Weight with driver (LBS): "10.5 (f) 11 (r) 3600" Chassis Notes: "Must conform to Mustang Challenge Rules. Tires conforming to Mustang Challenge rules are permitted. **This car is not eligible for the Runoffs until it has competed in 3 Super Tour events.**"
EP Base Weight Adjustment for H-Production X1/9 Spec Lines
#38255 from Matthew Brannon · Rule change · TB 25-06 (2025-06 Fastrack)
fasterHP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines.
In HP Spec Lines, change Weight as follows: Fiat X-1/9 & Bertone1500: “1790 1740 *1835 1784 **1880 1827” Fiat X-1/9 1300: “1650 1600 *1691 1640 **1733 1680” Fiat X-1/9 1300: “2060 2010” Fiat X-1/9 1500: “1950 1900”
slowerEP BMW Z4 03-05 restricted to 52mm flat plate intake restrictor.
In EP Spec Lines, BMW Z4 (03-05), add to Notes the following: “52mm Flat Plate Intake Restrictor.”
EP EP Fiat 124 Spider Competition Adjustment Request
#38498 from John Baucom · Rule change · TB 25-07 (2025-07 Fastrack)
fasterEP Fiat 124 Spider 1600 & 2000 weight drops 50 lbs to 2000; carburetors gain 2mm chokes to 36mm.
In EP Spec Lines, Fiat 124 Sport Spider 1600 & 124 Spider 2000, change as follows: Weight: "2050 2000" Carburetor No. & Type: "(2) Weber 40 IDF-40IFI, (2) Solex C40P116, 34 36mm choke(s) req’d, (2) Weber 45DCOE w/ 34 36 mm choke(s) on I.R. manifold or fuel injection."
STL Lotus Weight Reduction
#38772 from Club Racing Board · Rule change · TB 25-08 (2025-08 Fastrack)
fasterSTL/STU Lotus weight reduced: Evora GT4 to 2700 lbs, Elise Cup R to 2250 lbs, Elise/Exige SC to 2450-2550 lbs.
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"
EP HP Plymouth Arrow spec omission
#38995 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)
neutralHP Plymouth Arrow transmission max speeds clarified to 4 or 5.
In HP Spec Lines, Plymouth Arrow (76-80), add the following wording to Trans. Speeds(max): "4 or 5"
EP Add Wheel Diameter to Appendix G
#39008 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)
neutralEP, FP, HP wheel diameter added to Appendix G as absolute maximum specification.
In Appendix G.2.3, change as follows: "Rim width and diameter are is absolute maximums."
EP Add TB ID tolerance to general Prod rules
#39009 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)
neutralEP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only.
In GCR, Section 9.1.5.E., change as follows: 9.1.5.E.1.b.4: "The inside dimensions of the throttle body casting/housing (as measured at the throttle butterfly) must remain stock (tolerance of +/-.25mm), but the throttle body can otherwise be ported and polished." 9.1.5.E.2.b.4: "The inside dimensions of the throttle body casting/housing and all dimensions of the throttle butterfly must remain stock (tolerance of +/-.25mm)."
EP Please Lower Weight of 280Z
#38871 from Matthew Miller · Rule change · TB 25-09 (2025-09 Fastrack)
fasterEP Nissan 280Z minimum weight reduced from 2560 to 2400 lbs.
In EP Spec Lines, Nissan 280Z, change Weight (lbs) as follows: "(Effective 11/1/2025) 2560 2400 *2624 2460 **2688 2520"
EP Miata Weight Adjustment Follow Up
#38949 from Don Tucker · Rule change · TB 25-10 (2025-10 Fastrack)
fasterEP Mazda MX-5 1.8L 90-97 weight reduced to 2125 lbs from 2150 lbs.
In EP Spec Lines, Mazda MX-5 / Miata 1.8L (90-97), Effective 11/1/2025 make the following weight change: "2150 2125"
EP Weight Break for 1098 Midget / Sprite
#38970 from Kendall Jones · Rule change · TB 25-10 (2025-10 Fastrack)
In HP Spec Lines, Austin-Healey Sprite/Midget 1098cc, Effective 11/1/2025make the following weight change: "1630 1550"
EP HP Volvo 142 spec omission
#38994 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)
slowerHP Volvo 142/142E gains compression ratio limit 12.0:1 and valve lift limit .425".
In HP Spec Lines, Volvo 142/142E P-1800 Engine, Effective 11/1/2025 add the following wording to Notes: "Comp. Ratio limited to 12.0:1. Valve lift limited to .425”."
EP HP Mini DOHC 1.6
#38996 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)
slowerHP Mini Cooper 07-15 valve lift reduced to .390", from .450".
In HP Spec Lines, Mini Cooper (07-13) (includes 09-15 convertible and 12-15 Coupe), Effective 11/1/2025 make the following changes to the Notes: "Compression ratio limited to 11.0:1, Valve lift limited to .450”.390"."
EP Add to Rabbit description
#39019 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)
neutralFP and HP Volkswagen Rabbit descriptions updated: Convertible changed to Cabriolet in FP; Cabriolet added to three HP engine variants.
In FP Spec Lines, make the following spec line correction: "Volkswagen Rabbit (Includes Convertible Cabriolet)" In HP Spec Lines, make the following spec line correction: "Volkswagen Rabbit 1588 (Includes Cabriolet)" "Volkswagen Rabbit 1715 (Includes Cabriolet)" "Volkswagen Rabbit 1780 (Includes Cabriolet)"
EP Clean-up 9.1.5.E.7e
#39025 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)
neutralEP, FP, HP: rear drum brake to disc conversion clarified; rotors solid, diameter limited to largest front rotor permitted.
In GCR, Section 9.1.5.E.7., change as follows: "e. Cars fitted with rear drum brakes, can convert to rear disc brakes without penalty. Note that the “Brakes Std.” and “Brakes Alt.” listings on a vehicle’s spec line do not prohibit a car that was fitted with rear drum brakes stock, from converting to rear disc brakes under this rule. When converting from rear drum brakes to rear disc brakes: 1. Rear brake rotors must be solid and can be no larger in diameter than the largest permitted front brake rotor, as defined on the vehicle’s spec line. 2. Rear calipers and mounting brackets are unrestricted but must be made of a ferrous or aluminum material. The standard and alternate brake listings on a vehicle’s specification line, does not prohibit a car that was fitted with rear drum brakes as stock
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from converting to rear disc brakes under this rule. 3. The “Brakes Std.” and “Brakes Alt.” listings on a vehicle’s spec line do not prohibit a car that was fitted with rear drum brakes as stock from converting to rear disc brakes under this rule."
EP Add TB size to Ford Mustang (94-98) Spec Line
#39130 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)
neutralEP Ford Mustang (94-98) fuel injected throttle body inside diameter specified at 60.
In EP Spec Lines, Ford Mustang (94-98) add the following to the Fuel Injected Equipped Throttle Body Inside Diameter column: "60"
EP TR2 Notes E&O
#39180 from Anthony Parker · Rule change · TB 25-12 (2025-12 Fastrack)
unclearEP Triumph TR2-TR4A allows 5-speed gearbox without overdrive; removes Weber carb and weight specification.
In EP Spec Lines, Triumph TR2, 3, 3A, 4, 4A, TR4, TR4A, IRS, make the following change to the Notes: "Front apron assembly may be made of alternate material. Three (3) Weber 40 DCOE on IR manifold with 28mm chokes @ 1990 lbs. Laycock overdrive, may use 5 speed gearbox without overdrive."
EP Balance of Power
#39187 from Jim Simaras · Rule change · TB 25-12 (2025-12 Fastrack)
slowerEP BMW Z3 2.5L restrictor reduced 52mm to 50mm, weight increased to 2550 lbs base; five other BMW models get smaller restrictors.
In EP Spec Lines, make the following changes to Restrictors: BMW Z3 2.5L: "52mm 50mm Flat Plate Intake Restrictor" BMW Z3 2.8L (97-00): "55mm 53mm Flat Plate Intake Restrictor" BMW 328i/is E36 (96-99): "58mm 55mm Flat Plate Intake Restrictor" BMW 328i/ci E46 (01-06): "58mm 55mm Flat Plate Intake Restrictor" BMW 325i/is (E46) (01-06): "56mm 53mm Flat Plate Intake Restrictor" BMW 325is M-Technic (1994): "56mm 53mm Flat Plate Intake Restrictor" BMW 325i/is E-36 (92-95): "56mm 53mm Flat Plate Intake Restrictor"
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In EP Spec Lines, BMW Z3 2.5L, change Weight as follows: "2500 2550 *2563 2614 **2625 2678"
T1 Keep S2000 Classification
#39344 from David Mead · Rule change · TB 25-12 (2025-12 Fastrack)
unclearUnable to summarize: letter states intent but provides no actual rule changes to S2000 specification.
In T1 Spec Lines, reinstate Spec Line # 1139, Chevrolet Corvette C6 (05-13) Includes Z51, GrandSport, Z06, Z06 Carbon, as follows: Max Displ: "LS1, LS6 OEM" Min Weight: "3200" Required Restrictor: "70mm"
What the rules allowed changed as listed; this does not say what any particular car ran.