GT2 vs GT1 vs AS vs P2 pace at Buttonwillow Raceway Park
Quickest here:GT2 1:42.698 Tim Carroll, Cal Club 2026 qualifying · GT1 1:39.857 Michael McAleenan, Cal Club 2026 qualifying · AS 1:55.849 Roger Eagleton, Cal Club 2025 race · P2 1:09.928 Tim Day Jr, Cal Club 2023 qualifying
GT2GT1ASP2solid race · dashed qualifying · slower is lower
GT2GT1ASP2solid race · dashed qualifying · each class's best lap as a share of GT2's at the same event (the reference class, changeable above); 100% is level, higher is quicker
Event
GT2
GT1
AS
P2
Qual best
Race best
Trap
Qual best
Race best
Trap
vs GT2
% of GT2
Qual best
Race best
Trap
vs GT2
% of GT2
Qual best
Race best
Trap
vs GT2
% of GT2
Cal Club 2026 CALCL262026-02-21
1:42.698Tim Carroll · fastest of 8 · top 5 within 7.4s-3.120s (-2.95%)
1:44.128Tim Carroll · fastest of 8 · top 5 within 4.3s-2.798s (-2.62%)
155.7Rocky Crocker+37.8 mph (+32.1%)
1:39.857Michael McAleenan · fastest of 2-4.110s (-3.95%)
1:41.045Michael McAleenan · fastest of 2-1.260s (-1.23%)
167.6Michael McAleenan+53.8 mph (+47.3%)
-3.083squal -2.841s
97.0%qual 97.2%
1:56.812Ross Murray · fastest of 2+0.367s (+0.32%)
1:56.314Ross Murray · fastest of 2+0.465s (+0.40%)
135.2Ross Murray+26.5 mph (+24.4%)
+12.186squal +14.114s
111.7%qual 113.7%
1:37.278Tim Day Jr · only car+27.350s (+39.11%)
1:39.758Tim Day Jr · only car
155.4Tim Day Jr
-4.370squal -5.420s
95.8%qual 94.7%
24 rule changes (GT2: 8, GT1: 5, AS: 11)8 cars added · 3 induction · 3 weight · 1 aero · 1 engine · 8 wording · AS Chevy LS adds Edelbrock Performer RPM 71187 intake manifold with MSD 6014 ignition and 4776 Holly carburetor as spec line option. · GT1 adds Porsche 992.1 GT3 Cup (2022-2025) with OEM ABS, traction control, RSR bumper, canards, and any exhaust allowed. · GT2 Porsche 911 SC gains option of 4.0L 4V engine at 2350 lbs or 4.0L 2V at 2275 lbs. · M3 E92 classified in GT2 with 3999cc V8, 35mm restrictor, 3300 lbs minimum weight. · AS Ford Mustang Restricted Prep engines lose 3 mm restrictor plate, from 64 mm to 61 mm. · GT1-ST Acura NSX GT3 EVO 22 weight drops 100 lbs to 3000 lbs. · GT2 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. · GT2 Mazda BP engine 1839cc classified with 46mm turbo inlet restrictor, 2250 lbs minimum weight. · 991.2 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 Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft. · AS Cadillac CTS-V 04-07 Restricted Prep weight reduced 50 lbs to 3400. · Acura NSX GT3 EVO 22 reclassified from GT1 to GT1-ST with 3100 lbs minimum weight. · GT1 LS Limited Prep Engine expands to include LS1, LS2, LS3, LS6 with 11:1 max compression. · GT2 Porsche 911 Coupe & Targa may use 993 3.8 RSR rear deck lid or approved aftermarket reproductions. · AS Ford Mustang GT 5.0 2018- weight reduced from 3600 to 3525 lbs. · AS Ford Mustang GT 05-14 Restricted Prep Engine gains alternative gear ratios: 3.66, 2.43, 1.69, 1.32, 1.00, .65 · AS Ford Mustang GT 5.0L (15-17) flat plate restrictor reduced from 67mm to 64mm. · AS LS1/LS6 5.3L truck engine gains four approved intake part numbers: 12561269, 88894095, 89017363, 89017364. · AS Flotek Head plunge cut dimensions figure updated in GCR Section 9.1.6. · AS class notes cleanup: multiple Camaro, Firebird, CTS-V, Challenger, Mustang specs and fuel cell/ECM/head restrictions removed. · AS Spec Lines removes ECM flexibility restriction from five Cadillac and Chevrolet/Pontiac V8 models. · Acura NSX GT3 EVO 22 classified in GT1 with 3500cc twin turbo V-6, 3100 lbs, max RPM 7500. · GT2 Pontiac Fiero changes from FWD to RWD; hood bulge permitted for front engine relocation. · TA2 and STO OEM wings no longer exempt from rear wing height rule at roof peak.showhide
AS Edelbrock manifold (& timing kit) to Chevy LS Spec Lines Request #39055cars addedneutralAS Chevy LS adds Edelbrock Performer RPM 71187 intake manifold with MSD 6014 ignition and 4776 Holly carburetor as spec line option.
GT1 Request for Addition of Porsche 992.1 GT3 Cup into GT1 #39322cars addedneutralGT1 adds Porsche 992.1 GT3 Cup (2022-2025) with OEM ABS, traction control, RSR bumper, canards, and any exhaust allowed.
GT2 Allow Larger Air Cooled Engines in Porsche 911 GT2 #39249enginefasterGT2 Porsche 911 SC gains option of 4.0L 4V engine at 2350 lbs or 4.0L 2V at 2275 lbs.
GT2 Classify T1 BMW in GT2 #39408cars addedneutralM3 E92 classified in GT2 with 3999cc V8, 35mm restrictor, 3300 lbs minimum weight.
AS Restrictor Plate Change for Gen 2 Ford Coyote Engine #39501inductionslowerAS Ford Mustang Restricted Prep engines lose 3 mm restrictor plate, from 64 mm to 61 mm.
GT1 NSX Parity With Other GT3s Let Alone a GT1 Car #39311weight -100 lbsfasterGT1-ST Acura NSX GT3 EVO 22 weight drops 100 lbs to 3000 lbs.
GT2 Additional Body Options to Replace Older Stock Car Bodies #39086cars addedneutralGT2 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.
GT2 GT3 Turbo to GT2? #39365cars addedneutralGT2 Mazda BP engine 1839cc classified with 46mm turbo inlet restrictor, 2250 lbs minimum weight.
GT2 Tech Bulletins for GT2 and GT2-ST #39537induction -100 lbsslower991.2 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 1994 Mustang Spec Line Request #39104wordingunclearAS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft.
AS Cadillac CTS-V BOP Weight Change #38640weight -50 lbsfasterAS Cadillac CTS-V 04-07 Restricted Prep weight reduced 50 lbs to 3400.
GT1 RM 25-06 GT1 reclassify the Acura NSX GT3 EVO 22 to GT1-ST #39101cars addedneutralAcura NSX GT3 EVO 22 reclassified from GT1 to GT1-ST with 3100 lbs minimum weight.
GT1 Correction to Limited prep LS Chevy engine for GT1 #38902cars addedneutralGT1 LS Limited Prep Engine expands to include LS1, LS2, LS3, LS6 with 11:1 max compression.
GT2 Rear Deck Lid for Older Air-Cooled Porsche #38506wordingneutralGT2 Porsche 911 Coupe & Targa may use 993 3.8 RSR rear deck lid or approved aftermarket reproductions.
AS RE: Previous Letter 37695 Update #38245weight -75 lbsfasterAS Ford Mustang GT 5.0 2018- weight reduced from 3600 to 3525 lbs.
AS Errors and Omissions #38234wordingneutralAS Ford Mustang GT 05-14 Restricted Prep Engine gains alternative gear ratios: 3.66, 2.43, 1.69, 1.32, 1.00, .65
AS Errors and Omission #38055inductionslowerAS Ford Mustang GT 5.0L (15-17) flat plate restrictor reduced from 67mm to 64mm.
AS Request to Add LS1/LS6 Intakes for 5.3L Truck Engine EnO #38197wordingneutralAS LS1/LS6 5.3L truck engine gains four approved intake part numbers: 12561269, 88894095, 89017363, 89017364.
AS Flotek Head Plunge Cut Inconsistencies #37502wordingunclearAS Flotek Head plunge cut dimensions figure updated in GCR Section 9.1.6.
AS Notes clean up #37693wordingneutralAS class notes cleanup: multiple Camaro, Firebird, CTS-V, Challenger, Mustang specs and fuel cell/ECM/head restrictions removed.
AS Race memo #37902wordingunclearAS Spec Lines removes ECM flexibility restriction from five Cadillac and Chevrolet/Pontiac V8 models.
GT1 Request to Classify Acura NSX GT3 Evo 22 #37367cars addedneutralAcura NSX GT3 EVO 22 classified in GT1 with 3500cc twin turbo V-6, 3100 lbs, max RPM 7500.
GT2 Hood Bulge allowed #37000wordingunclearGT2 Pontiac Fiero changes from FWD to RWD; hood bulge permitted for front engine relocation.
GT2 OEM Wing Adjustment #37590aeroslowerTA2 and STO OEM wings no longer exempt from rear wing height rule at roof peak.
Cal Club 2025 CALCL252025-02-22
1:45.818Brad McAllister · fastest of 6 · top 5 within 14.6s
1:46.926Brad McAllister · fastest of 6 · top 5 within 13.3s
117.9Guy Laidig
1:43.967Michael Lewis · only car
1:42.305Michael Lewis · only car
113.8Michael Lewis
-4.621squal -1.851s
95.7%qual 98.3%
1:56.445Roger Eagleton · fastest of 3 · top 3 within 4.0s
1:55.849Roger Eagleton · fastest of 4 · top 4 within 5.3s
108.7Roger Eagleton
+8.923squal +10.627s
108.3%qual 110.0%
67 rule changes (GT2: 23, GT1: 15, AS: 19, P2: 10)16 cars added · 9 induction · 7 weight · 6 engine · 2 aero · 2 tyres & wheels · 24 wording · 1 other · GT2 STO aftermarket ABS weight penalty reduced from 100 lbs to 50 lbs. · AS Ford Mustang Coyote engines increase restrictor to 80mm from 64mm or 67mm. · AS Mustang GT 05-14 4.6L loses 300 lbs; 15-17 and 2018+ models lose 61mm and 60mm restrictors respectively. · AS class gear ratio options specified for multiple American muscle cars, including Cadillac CTS-V, Chevrolet Camaro, Ford Mustang, Dodge Challenger, and Pontiac GTO. · AS LS-engine cars gain ECU freedom; Camaro/Firebird 93-02 LS1 removes fuel cell location restriction. · GT1 LS1 Limited Prep engine added, 2600 lbs with driver, 383 cubic inches max, hydraulic roller cam, 750 cfm carb. · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof requirement. · GT1-ST restrictor sizes removed for 13 cars; new specs not printed in letter. · GT2 Panoz Esperante GTS adds 2013-2016 Ford EcoBoost Twin Turbo V-6 3496cc engine, 2600 lbs. · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof requirement. · GT2 Sunbeam Tiger gains Holly 650 cfm carburetor alternate options PN #80541-1 and #80541-2. · GT1-ST Lamborghini Huracan GT3 Evo and 2019+ GT3 both shift to Unrestricted from 39mm and 52mm restrictors. · P2 2000cc Pinto engine car minimum weight set to 1335 lbs. · GT1 Mazda 26B engine classified at 2850 lbs minimum weight. · AS Ford Mustang GT models gain alternate transmission ratio options for 2024-09-01. · GT2-ST allows aftermarket replacement differential housings if exact equivalents. · GT4 cars now permitted in GT2-ST with factory restrictor, must comply with 2012 STO rules, slicks allowed with 100-pound penalty. · AS Ford Mustang GT 5.0L (2018-) classified at 3600 lbs with 60mm restrictor, Brembo BBK permitted. · AS Chevrolet Camaro 1LE (2016-) classified with 3600 lbs minimum weight, 60mm restrictor, 275 tires. · AS Chevrolet/Pontiac Camaro & Firebird 82-92 5.7L LS1 classified at 3200 lbs with 65mm restrictor plate required. · AS Chevrolet Camaro, Firebird, and Ford Mustang models permitted to use Flo Tek cylinder heads. · GT2-ST Acura NSX minimum weight raised to 3000 lbs, restrictor increased to 45mm TIR. · GT1 Camaro 1993-2002 classification updated; 2010- model separately classified. · GT2-ST Acura NSX minimum weight raised to 3000 lbs, restrictor increased to 45mm TIR. · GT2-ST Corvette 14-19 LS2 restrictor increases from 78mm to 80mm flat plate. · P2 Spec ECU engine modifications clarified: oil system, ECU, and exhaust unrestricted only. · P2 FIA Group CN spec notes clarified: Series changed to Challenge, documentation requirement moved to online link. · AS Camaro/Firebird and GTO LS1 connecting rods approved: Callies CSC6100DS6A2AH, Scat 2-1CR6100-944, GM 12649190. · AS Cadillac CTS-V, Chevrolet Camaro SS, Dodge Challenger, Ford Mustang GT, Pontiac GTO allowed 11" wheels until 3/1/25. · Chevrolet Camaro, Pontiac Firebird 70-81 Full Prep classified AS at 3400-3600 lbs with 250 lb weight reduction. · AS class: multiple cars gain fuel cell placement note allowing 24 inches from standard tank, unrestricted filler location. · Chevrolet Camaro 16- Full Prep classified into AS at 3400 lbs with 250 lb weight reduction. · AS adds Ford Mustang GT 05-14 Restricted prep Engine with 62mm FPR, 3400 lbs minimum, 18-inch wheels. · Chevrolet Corvette C8 (2020–) classified into GT2-ST with 6162cc displacement, 3300 lbs minimum weight, 71mm restrictor. · 2015 Mitjet ST added to GT2, must run per VTS specifications with complete FIA form CdM008. · GT1, GT2, GT3, GTL, GTX rear spoiler maximum surface area limit of 295.0 square inches removed. · GT1/GT2/GT3/GTL/GTX Direct Injection now permitted if OE, using only OE pump, hoses, injectors. · GT2/3 Nissan, Mazda, Mitsubishi 4G93, QR25DE/DD, QE25DE/DD Direct Injection now permitted per 9.1.2.F.7.5.E. · GT1, GT2, GT3, GTL, GTX rear spoiler maximum surface area limit of 295.0 square inches removed. · GT1/GT2/GT3/GTL/GTX Direct Injection now permitted if OE, using only OE pump, hoses, injectors. · GT2 Chevrolet Corvette 7011 OEM 7 liter weight reduced 150 lbs, to 3125 lbs. · GT2/3 Nissan, Mazda, Mitsubishi 4G93, QR25DE/DD, QE25DE/DD Direct Injection now permitted per 9.1.2.F.7.5.E. · Lamborghini Huracan GT3 EVO(1) and GT3 added to GT1-ST at 3000 and 3100 lbs minimum weight respectively. · GT1 Trick Flow Specialties Ultra 18 Degree GM Cylinder Head Part #TFS-3181T001-CO1 allowed. · GT2-ST Dodge Viper hybrid kit restrictor reduced from 50mm to 45mm flat plates. · P2 AMAC modified engine range clarified to 2008 and older stock engines only, restrictor 38mm, weight 1025 lbs. · P2 Suzuki GSX-R1000 07/08 engine crankcase may swap to GSX-S1000 16/19 part #11301-04840. · GTL spec lines moved to contiguous position with GT2 and GT3; GTA category and spec lines renumbered and moved behind GTL. · GTL spec lines moved to contiguous position with GT2 and GT3; GTA category and spec lines renumbered and moved behind GTL. · P2 Table 1 corrects engine date ranges and brand specifications for Stock and Modified engines across multiple car models. · GT2-ST Dodge Viper including Comp Coupe, ACR/ACR-X with VRL front fascia loses 100 lbs. · GT2 Mazda 20B 3 rotor loses 220 lbs, to 2280, consolidating two spec lines. · AS crate motor part number specified: GM Performance CT400 P/N 19370604 engine assembly for GM vehicles. · AS Spec Lines Ford Mustang GT 5.0L (15-17) max wheel size increases to 19.0 inches. · AS Dodge Challenger 5.7L/6.1L/6.4L V8 now permits SPC-66045 alternate front upper control arms. · AS Dodge Challenger 5.7L/6.1L/6.4L V8 allows alternate front brake caliper adapters for updated or backdated components. · GT2 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. · GT2 Corvette C7 restrictor increases from 73mm to 77mm flat plate, removing weight penalty. · Fields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight. · 2009-2012 Porsche Cayman S classified in GT2, 3.4L, RWD, no PDK transmission allowed. · Fields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight. · P2 side body height requirement clarified: outermost surface between wheel openings must equal front axle centerline height. · P2 closed cockpit single seat cars now prohibited unless specifically allowed in Table 1. · GT1 Mercedes AMG GT3 16-19 preparation wording changed to per FIA GT3 homologation. · GT2 Ginetta G56 GTA may now use Factory installed ProMap ECU Map. · P2 engine table wording updated; redundant effective date language removed. · P2 motorcycle engines: 2011+ Kawasaki restrictor reduced to 34mm, minimum weight raised to 1100 lbs; 2009+ other brands weight raised to 1100 lbs.showhide
GT2 GT2/ST - Remove Aftermarket/Racing ABS penalty #36538weightfasterGT2 STO aftermarket ABS weight penalty reduced from 100 lbs to 50 lbs.
AS Increase Coyote Engine Restrictor to 80mm #36177inductionfasterAS Ford Mustang Coyote engines increase restrictor to 80mm from 64mm or 67mm.
AS Performance Pack for 2015+ Mustang #36867enginefasterAS Mustang GT 05-14 4.6L loses 300 lbs; 15-17 and 2018+ models lose 61mm and 60mm restrictors respectively.
AS Gear Ratios #37131wordingneutralAS class gear ratio options specified for multiple American muscle cars, including Cadillac CTS-V, Chevrolet Camaro, Ford Mustang, Dodge Challenger, and Pontiac GTO.
AS ECU specs for LS engine #37208enginefasterAS LS-engine cars gain ECU freedom; Camaro/Firebird 93-02 LS1 removes fuel cell location restriction.
GT1 Addition of a limited prep LS Chevy engine for GT1 #37045cars addedneutralGT1 LS1 Limited Prep engine added, 2600 lbs with driver, 383 cubic inches max, hydraulic roller cam, 750 cfm carb.
GT1 Correct language regarding OEM Areo Devices #37137wordingneutralTA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof requirement.
GT1 GT1-ST Adjustments #37481inductionunclearGT1-ST restrictor sizes removed for 13 cars; new specs not printed in letter.
GT1 Lamborghini Huracan GT3 Evo Restrictor Help #36254inductionfasterGT1-ST Lamborghini Huracan GT3 Evo and 2019+ GT3 both shift to Unrestricted from 39mm and 52mm restrictors.
P2 2000 cc Pinto Engine Car Weight #37187weightslowerP2 2000cc Pinto engine car minimum weight set to 1335 lbs.
GT1 Request to Classify Mazda 26B Engine #36230cars addedneutralGT1 Mazda 26B engine classified at 2850 lbs minimum weight.
AS Mustang transmission ratios #36662wordingunclearAS Ford Mustang GT models gain alternate transmission ratio options for 2024-09-01.
GT2 GT4 cars may run in GT2-ST #36235cars addedneutralGT4 cars now permitted in GT2-ST with factory restrictor, must comply with 2012 STO rules, slicks allowed with 100-pound penalty.
AS Request for Classification of 2018-2023 mustang In #35764cars addedneutralAS Ford Mustang GT 5.0L (2018-) classified at 3600 lbs with 60mm restrictor, Brembo BBK permitted.
AS 6th gen Camaro limited prep #35733cars addedneutralAS Chevrolet Camaro 1LE (2016-) classified with 3600 lbs minimum weight, 60mm restrictor, 275 tires.
AS Chevrolet/Pontiac Camaro & Firebird (82-92) 5.7L V8 LS1 Alum BLK #35825cars addedneutralAS Chevrolet/Pontiac Camaro & Firebird 82-92 5.7L LS1 classified at 3200 lbs with 65mm restrictor plate required.
AS Full Prep Head #35891otherneutralAS Chevrolet Camaro, Firebird, and Ford Mustang models permitted to use Flo Tek cylinder heads.
GT1 Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslowerGT2-ST Acura NSX minimum weight raised to 3000 lbs, restrictor increased to 45mm TIR.
GT1 Camaro 1993- and 2010- #35652wordingneutralGT1 Camaro 1993-2002 classification updated; 2010- model separately classified.
GT2 Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslowerGT2-ST Acura NSX minimum weight raised to 3000 lbs, restrictor increased to 45mm TIR.
GT2 Request to Eliminate the FPR from the Corvette (-2013) with LS2 #35878inductionfasterGT2-ST Corvette 14-19 LS2 restrictor increases from 78mm to 80mm flat plate.
P2 E&O - Correct FIA Group CN spec line notes #35900wordingneutralP2 FIA Group CN spec notes clarified: Series changed to Challenge, documentation requirement moved to online link.
AS Restricted Prep Aftermarket Parts Request #35682wordingneutralAS Camaro/Firebird and GTO LS1 connecting rods approved: Callies CSC6100DS6A2AH, Scat 2-1CR6100-944, GM 12649190.
AS Allowance of 11 #35824tyres & wheelsfasterAS Cadillac CTS-V, Chevrolet Camaro SS, Dodge Challenger, Ford Mustang GT, Pontiac GTO allowed 11" wheels until 3/1/25.
AS Request to Classify 1970-1981 Camaro and Firebird in AS #33659cars addedneutralChevrolet Camaro, Pontiac Firebird 70-81 Full Prep classified AS at 3400-3600 lbs with 250 lb weight reduction.
AS Fuel Cell 12 #34194wordingneutralAS class: multiple cars gain fuel cell placement note allowing 24 inches from standard tank, unrestricted filler location.
AS Please Classify the 6th Gen Into AS. #35448cars addedneutralChevrolet Camaro 16- Full Prep classified into AS at 3400 lbs with 250 lb weight reduction.
AS spec lines #35713cars addedneutralAS adds Ford Mustang GT 05-14 Restricted prep Engine with 62mm FPR, 3400 lbs minimum, 18-inch wheels.
GT2 Classify Corvette C8 (2020- ) into GT2/ST #33759cars addedneutralChevrolet Corvette C8 (2020–) classified into GT2-ST with 6162cc displacement, 3300 lbs minimum weight, 71mm restrictor.
GT2 Requesting classification for a 2015 Mitjet ST in GT2 #35408cars addedneutral2015 Mitjet ST added to GT2, must run per VTS specifications with complete FIA form CdM008.
GT1 Rear Blade Spoiler Clarification #35261aerofasterGT1, GT2, GT3, GTL, GTX rear spoiler maximum surface area limit of 295.0 square inches removed.
GT1 GT Direct Injection allowance and rules #35437enginefasterGT1/GT2/GT3/GTL/GTX Direct Injection now permitted if OE, using only OE pump, hoses, injectors.
GT1 GT2/3 remove Direction Injection not allowed in Spec line notes #35439inductionfasterGT2/3 Nissan, Mazda, Mitsubishi 4G93, QR25DE/DD, QE25DE/DD Direct Injection now permitted per 9.1.2.F.7.5.E.
GT2 Rear Blade Spoiler Clarification #35261aerofasterGT1, GT2, GT3, GTL, GTX rear spoiler maximum surface area limit of 295.0 square inches removed.
GT2 GT Direct Injection allowance and rules #35437enginefasterGT1/GT2/GT3/GTL/GTX Direct Injection now permitted if OE, using only OE pump, hoses, injectors.
GT2 REDUCE C6 CORVETTE WEIGHT WITH OEM 7 LITER ENGINE REDUCE BY 150LB #35385weight -150 lbsfasterGT2 Chevrolet Corvette 7011 OEM 7 liter weight reduced 150 lbs, to 3125 lbs.
GT2 GT2/3 remove Direction Injection not allowed in Spec line notes #35439inductionfasterGT2/3 Nissan, Mazda, Mitsubishi 4G93, QR25DE/DD, QE25DE/DD Direct Injection now permitted per 9.1.2.F.7.5.E.
GT1 Request for Acceptance of Lamborghini Huracan GT3 in GT1-ST #34929cars addedneutralLamborghini Huracan GT3 EVO(1) and GT3 added to GT1-ST at 3000 and 3100 lbs minimum weight respectively.
GT1 Cylinder heads #35040wordingneutralGT1 Trick Flow Specialties Ultra 18 Degree GM Cylinder Head Part #TFS-3181T001-CO1 allowed.
GT2 Dodge Viper Gen 3 hybrid Kit Update Request #35200inductionslowerGT2-ST Dodge Viper hybrid kit restrictor reduced from 50mm to 45mm flat plates.
P2 E&O - Clarify B.1 modified engine range in AMAC spec lines #35225wordingneutralP2 AMAC modified engine range clarified to 2008 and older stock engines only, restrictor 38mm, weight 1025 lbs.
P2 Replacement Engine Crankcase for 07/08 Suzuki GSX-R1000 Engines #35340engineunclearP2 Suzuki GSX-R1000 07/08 engine crankcase may swap to GSX-S1000 16/19 part #11301-04840.
GT1 Errors in GTCS Headings and Use of the Terms Category and ClassChange existing GTL and GTA Rules #34453wordingneutralGTL spec lines moved to contiguous position with GT2 and GT3; GTA category and spec lines renumbered and moved behind GTL.
GT2 Errors in GTCS Headings and Use of the Terms Category and ClassChange existing GTL and GTA Rules #34453wordingneutralGTL spec lines moved to contiguous position with GT2 and GT3; GTA category and spec lines renumbered and moved behind GTL.
P2 Correct Table 1 for Engine Date Range Specifications #35182wordingneutralP2 Table 1 corrects engine date ranges and brand specifications for Stock and Modified engines across multiple car models.
GT2 Late E & O #34966weightfasterGT2-ST Dodge Viper including Comp Coupe, ACR/ACR-X with VRL front fascia loses 100 lbs.
GT2 GT2 Mazda 20B 3 rotor ENO #34765weight -220 lbsfasterGT2 Mazda 20B 3 rotor loses 220 lbs, to 2280, consolidating two spec lines.
AS Crate Motor Part Numbers #32944wordingneutralAS crate motor part number specified: GM Performance CT400 P/N 19370604 engine assembly for GM vehicles.
AS Request wheel size change #33007tyres & wheelsfasterAS Spec Lines Ford Mustang GT 5.0L (15-17) max wheel size increases to 19.0 inches.
AS Alternative Upper Front Control Arms for Dodge Challenger #33352wordingneutralAS Dodge Challenger 5.7L/6.1L/6.4L V8 now permits SPC-66045 alternate front upper control arms.
AS Front Brake Caliper Adapters for Dodge Challenger #33353wordingneutralAS Dodge Challenger 5.7L/6.1L/6.4L V8 allows alternate front brake caliper adapters for updated or backdated components.
GT2 appendix letter #33635 #34206wordingneutralGT2 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.
GT2 Remove Weight and Restrictor Penalty for Corvette C7 Body #34342inductionfasterGT2 Corvette C7 restrictor increases from 73mm to 77mm flat plate, removing weight penalty.
GT1 Please classify Fields Cardinal V8 #33784cars addedneutralFields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight.
GT2 Request to class 2011 Porsche Cayman S #33771cars addedneutral2009-2012 Porsche Cayman S classified in GT2, 3.4L, RWD, no PDK transmission allowed.
GT2 Please classify Fields Cardinal V8 #33784cars addedneutralFields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight.
P2 Clarify minimum side body height requirement #34143wordingneutralP2 side body height requirement clarified: outermost surface between wheel openings must equal front axle centerline height.
P2 Clarify closed cockpit single seat car allowance #34144wordingneutralP2 closed cockpit single seat cars now prohibited unless specifically allowed in Table 1.
GT1 Mercedes AMG GT3 Notes #33804wordingneutralGT1 Mercedes AMG GT3 16-19 preparation wording changed to per FIA GT3 homologation.
GT2 Adding Ginetta G56 GTA Factory ProTune for GT2 Class #33825wordingunclearGT2 Ginetta G56 GTA may now use Factory installed ProMap ECU Map.
P2 Remove redundant effective date language and update engine table #34012wordingneutralP2 engine table wording updated; redundant effective date language removed.
P2 E&O - Correct dimensional equivalents #34038engineslowerP2 motorcycle engines: 2011+ Kawasaki restrictor reduced to 34mm, minimum weight raised to 1100 lbs; 2009+ other brands weight raised to 1100 lbs.
Cal Club 2023 CALCL232023-02-24
1:09.928Tim Day Jr · fastest of 2
200 earlier rule changes on record, in force before Cal Club 2023 (from 2019)44 cars added · 35 weight · 19 induction · 17 engine · 6 aero · 6 tyres & wheels · 4 suspension & brakes · 66 wording · 3 other · GT1 sequential transmission weight penalty reduced from 50 to 25 lbs. · GT1-ST Porsche 992 GT3 Cup classified with 3997cc displacement, 2950 lbs minimum weight. · GT2 Mazda 13B Street Port turbo changes from EFR 76/70 to BW7670 or Garrett G30-660 with 46mm TIR at 2280 lbs. · GT2 Porsche SOHC 2478/2681/2992 turbo sizes increase from 42mm to 44mm SIR to TIR. · GT2-ST Chevrolet Corvette 14-19 L76 5967 restrictor increases from 70 to 73 mm. · GT2 Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines newly classified in spec line. · GT2 Mazda 13B Street/Bridge Port turbocharger changes from EFR 70/76 to 76/70, compressor from 42mm to 46mm. · GT2-ST BMW E36/46 spec line adds MA Shaw carbon/composite door offerings to Notes. · GT3 normally aspirated cars may use intake chokes instead of SIRs, fitted to each carburetor barrel, same size as required SIR. · GT3 2.0L 4-valve non-turbo engines may run unrestricted at 2060 lbs instead of with a choke restriction. · GT2 Porsche 991.1 TBR 70–72mm, 991.2 weight 3100–3000lbs TBR 65–67mm, ABS penalties removed; GT2-ST Corvette LS engines flat plate 75–78mm, LS7 65–68mm; Viper weights 3275–3125lbs. · Sebeco NP01-EVO and Elan NP01 Mazda 2.0L MZR added to P2, 1600 lb minimum, no restrictor required. · P2 Radical SR3/SR4/Cup/Club Sport/Pro-Sport/PR6 removes assisted shifting requirement across all spec lines. · P2 chassis rules clarified to allow composite materials in non-fully-composite construction; anti-intrusion panel attachment standardized; Stohr and converted F600 cars added with specific allowances. · Unable to summarize: the change to P2 Engine Table Spec Line B.1 is not detailed in the provided text. · GT2 TA2 and GTA throttle body part numbers updated to GM 90mm electronic #12570790 or Edelbrock 90mm mechanical #33869 or #3870. · GT1 Trans Am bodywork weight penalty reduced from 100 lbs to 75 lbs. · GT1 Chevrolet RO7, Ford FR9, and Dodge R7 weight penalties reduced from 50 to 25 lbs. · GT2 TA2 and GTA throttle body part numbers updated to GM 90mm electronic #12570790 or Edelbrock 90mm mechanical #33869 or #3870. · GT2 Ginetta G56 GTA gains optional 18" x 9" and 18" x 10" wheels. · GT2/ST BMW E36/E46 now allows MAShaw body kit parts: wide body, bumpers, fenders, rockers, flairs. · GT2 Chevrolet Corvette L76 5967 restrictor increases from 73mm to 74mm. · AS allows Hoosier W2 tyre option in addition to R7, R6, WET/H20. · AS Dodge Challenger 08-20 adds two transmission ratio options: 2.97, 2.10, 1.45, 1.00, 0.74, 0.50 or 2.26, 1.58, 1.19, 1.00, 0.77, 0.63. · GT taillights may now be original style or a panel graphic with functioning red LED brake lamps; wording change only. · GT taillights may now be original style or a panel graphic with functioning red LED brake lamps; wording change only. · Ginetta GTA G56 added to GT2 as spec car: 2600 lbs, 3.7L Ford V6 sealed, 6-speed Quaife sequential. · GT1 TransAm bodywork allowed with 100 lb. weight penalty. · GT2 BMW E36/E46 carbon roof and door suppliers added to notes: Lang Racing, 2M Automotive, Flossmann, MA Shaw. · GT2-ST BMW E46 M3, E36, Z3, 5000cc V8 can use 95mm S54 crankshaft at +150 lbs. · Audi R8 GT4 classified to GT2 with 5.2L displacement, 3000 lbs minimum weight, per factory specs restrictor. · AS Cadillac CTS-V 6.0L V8 removes 50 lbs weight penalty for 295 tire size. · GT2 shock absorber attachment points clarified as moveable; wording correction only. · GT2 Porsche 104.0 x 88.0 engine weight increases from 1950 to 2090 lbs; 2V variants may use Borg Warner EFR 76/70 42mm turbo. · P2 chassis construction rules clarified: fully composite or partially composite requiring composite for mobility allowed; partial composite must roll without composite parts. · P2 classification wording cleaned up in GCR section 9.1.8.C and Contents. · P2 Oldsmobile cam rules clarify aftermarket manufacturer requirements; wording only. · Mercedes Benz AMG GT3 classified in GT1 at 3050 lbs with 40mm restrictors, prepared per FIA GT3 homologation. · GT1 wheels: 18-inch tyres get wider rear allowance, from 13 to 14 MAX inches. · Ginetta G40 classified in GT2 with Mazda MZR/L5-VE engine, 2488cc or 2399cc, 1950 lbs base weight. · Toyota Supra GT4 added to GT2-ST: 3000cc, 3000 lbs minimum, factory restrictor. · GT2 Porsche 944/924 may use ERC 76/70 Turbo instead of Jayco super 50. · P2 adds Beasley B2 spec line with 1350 lbs, Mazda 12A, 40.5mm venturi, 16.5in wing. · P2 wing specs correct terminology from 'cord' to 'chord' for 16.5in single or dual element wings. · P2 Converted F5 cars reclassified as Converted F500 cars; suspension must comply with F500 requirements, minimum width 55 inches. · GT1 allows 17-inch wheels newly; 18-inch wheels require 50 lb penalty; maximum widths 12 front/13 rear, or 13/14 for 18-inch. · GT2 Porsche Cayman 05-15 turbo restrictor increases from 70mm to 75mm. · P2 motorcycle engines increase to 1505cc max, two-stroke to 1205cc max; automotive engines gain 50 lbs minimum weight to 1350. · SMG long tube headers: Borla PN 17237 discontinued, Kooks PN 11312000 and American Racing PN MT3-05134300LSNC approved alternatives. · AS Mercury Capri (79-86) removed as individual spec line, merged into Ford Mustang (79-93) spec line. · AS Spec Mustang SMG loses 3.73 gear ratio and 355/300 mm brake specification. · AS Chevrolet, Pontiac, Ford full prep engines now permit alternate cylinder heads with restrictor plate ALL26180 and 1.250 inserts ALL26186 for regional competition. · GT2 Porsche Cayman 05-15 uses Throttle Body Restrictor instead of Flat Plate Restrictor at 2700 lbs. · P2 Control Area definition narrowed; aerodynamic attachments and vertical structures like turning vanes now prohibited. · P2 Engine Table Spec Line B.1 changed effective 1-1-22, details not provided in excerpt. · P2 Control Area definition clarified: floor extensions and aerodynamic attachments on bottom or top side now explicitly included. · AS Chevrolet/Pontiac Camaro & Firebird 93-02 now allow BMR AA004 or UMI 2310 adjustable front upper control arms. · AS Pontiac GTO 04-06 LS1 to 3300 lbs, LS2 to 3350 lbs on 295 tire. · GT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight. · GT2 Mazda 13B street port adds EFR 70/76 turbo with 42mm restrictor at 2280 lbs. · GT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight. · GT2 Dodge Viper Comp Coupe ACR/ACR-X loses 100 lbs minimum weight to 3275. · P2 CN Honda K20A-FD2 engine rebuild rules clarified: machining prohibition replaced with specific restrictions on balancing, porting, polishing, valve jobs, cylinder honing. · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two sections and 6010 to 6014X in TA2 Appendix. · 04-06 World Challenge Pontiac GTO added to GT2-ST: 6062 cc, 3000 lbs minimum, unrestricted. · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two sections and 6010 to 6014X in TA2 Appendix. · Grullon GT with 2.0L K20 moved from GTX to GT2-ST, minimum weight 2350 lbs, unrestricted. · Converted F5 cars in P2 minimum width reduced to 55 inches from F5 spec. · P2 clarifies minimum body width requirement between front and rear wheels for Ralt RT40, RT41, Swift 008, 014. · GT2-ST Porsche Cayman restrictor increases from 65mm to 75mm flat plate at 2700 lbs. · GT2 Dodge Viper including Comp Coupe, ACR/ACR-X minimum weight reduced 100 lbs to 3275 in VRL Spec. · TA2 minimum weight set to 2930 lbs with free tire make and size. · AS Cadillac CTS-V 6.0L V8 removes 50 lbs tire size penalty, making it lighter. · AS consolidates seven SN95 Mustang spec lines into three: 94-04 including Cobra, 94-95 5.0/5.8, and 96-04 4.6L two/four valve. · AS Camaro/Firebird LT1/LS1 transmission code changes to 6362; Mustang GT 4.6L/5spd changes to 5.0L/6spd with 300 lbs weight reduction. · AS Camaro/Firebird and Mustang GT gear ratio specifications restored with alternate sets permitted. · AS Chevrolet Camaro & Firebird, Ford Mustang variants, Mercury Capri minimum weights increase 50 lbs across all model years. · P2 tonneau covers now allowed to meet minimum dimensions; equipment attachment requirements clarified. · P2 multiple chassis models remove effective dates from Table 1 specifications. · P2 engines limited to 4 valves per cylinder maximum across all three spec lines. · GT2 Sunbeam SBF 302 engine firing order option now explicitly allows Boss 302 variant. · AS Mustang 4.6L/5spd loses 300 lbs; 5.0L/6spd gains 56mm restrictor requirement. · AS CTS-V LS6 and LS2 may now use Driveshaft Shop carbon fiber driveshaft for durability. · AS Chevrolet Camaro SS V8 6.2L model years extended from 10-13 to 10-15. · GT2-ST Corvette (-2019) LS2 and L76 5967cc gain 100 lbs minimum weight to 3100; 6162cc variants gain 50–100 lbs; 7011 gains 100–50 lbs; L76 restrictor opens 70 to 73 mm. · GT2 rear engine opening location requirement removed. · GT2 Ford Mustang/Thunderbird Boss 302 firing order now optional from later SBF 302 versions. · P2 adds new spec line for 2-cycle 3-cylinder engine up to 820cc with 10 front and 14-15 rear wheel width. · GT2 ABS braking systems now allowed if shown on individual Spec Line. · GT2 Corvette C6 and C7 spec lines clarified and split; C7 LS2/L76/LS3/LT1/LS7 weights increased 100–150 lbs effective 3/1/2021. · Ford Mustang GT 5.0L 15-17 Restricted Preparation classified in AS with 55mm flat plate restrictor required. · AS underhood bracing on stock hoods, trunks, and rear decks may be modified or removed. · AS Cadillac CTS-V 04-07 with 295 tire drops to 3450 lbs; Camaro SS V8 10-13 275 tire removed; Challenger 08-20 gains 315 tire option at 3600 lbs. · AS Camaro & Firebird (93-02) and Mustang GT (05-14) specifications restored with 200 lb weight reduction for permitted heads. · GT2 Ford Mustang/Thunderbird Boss 302 firing order becomes unrestricted. · GT2 BMW E46 M3 weight reduced from 2600 to 2500 lbs. · AS Dodge Challenger 08-20 gains 6.1L and 6.4L V8 options; 5.7L weight rises to 3500 lbs on 295 tyres, 3600 on 315 tyres. · AS Camaro/Firebird (93-02) and Mustang Coupe GT (05-14) consolidated into single specs with 100 lb and 300 lb weight reductions respectively. · GT2 Chrysler/Dodge/Plymouth 2429cc DOHC engine classified at 1950 lbs, unrestricted fuel induction. · P2 Honda K20A-FD2 intake restrictor reduced from 55mm to 50mm, making cars faster. · GT2 stock car bodies removal rescinded; 1997-current year commercially available stock car bodies remain allowed. · GT2 Appendix L renumbering eliminates sections .17 through .19 after 4.8.4.2.10.3.6. · GT2 TA2 wing width maximum set to 65 -5/16 inches, previously undefined. · GT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line. · GT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line. · GT2 Chevrolet Corvette -2019 LS1/LS6 allows DORMAN part # 615-900 alternate intake manifold. · GT2 Porsche 997.2 GT3 Cup minimum weight drops to 2900 lbs. · P2 rear wing requirements clarified: standard wing 6×12 inches, end plates 14-inch square; alternate 110cm width wing 9×18 inches, end plates 14×18 inches. · AS Dodge Challenger 5.7L V8 gets iron block requirement, 10.5:1 compression max, intake valve 12.7 mm, exhaust 12.3 mm, intake duration 188°, exhaust duration 205°. · AS Dodge Challenger 08-14 rear spoiler part number changes from 1GL20RXF to 1GL20TZZAB. · GT1 adds Trans Am spec engines: Chevrolet R07, Ford FR9, Dodge R7, each with 50 lbs. weight penalty. · GT2 BMW E46 M3, E36, Z3, and 5000cc V8 gain Trans Am SGT spec allowance: regular shifter 3000 lbs., paddle shifter plus 150 lbs. · GT2 allows up to four hood/fender louvered panels, max 600 sq inches total, min five slots each, mounted in front of windscreen. · AS class pursues specified list of eligible tires; details of tire changes not provided in letter. · AS class pursuing specified list of eligible tires; details pending further communication. · No restrictor plate change implemented; 2021 AS Mustang Coyote under evaluation. · AS 2005-2009 Restricted Prep 4.6 3V now permits conversion to 2 valve configuration. · AS Ford Mustang Coupe GT 4.6L 3V Restricted Prep now permits Ford Performance camshaft kit P/N-M-6550-3V. · 2010-2014 Camaro reclassified to AS; full preparation classification approved effective 2020-07-01. · AS class cylinder head replacement options under review; implementation planned for 2021 season. · AS Mustang, Camaro, Firebird, Capri max brake rotor diameter increases from 12.2 to 13.1 inches. · AS rotor diameter increase approved; see Fastrack letter #28748 for details. · TA2 Gurney flap wording clarified: terminology standardized to 'Gurney flap', height limits and thickness specifications remain 0.50 inch / 0.625 inch or 0.375 inch / 0.0625 inch depending on configuration. · STO rear wing wording clarified: 'wicker' changed to 'Gurney flap' in maximum chord and mounting height rules. · GT1 Gurney flap wicker clarification: terminology standardized from lips/tabs/wicker to flaps throughout specifications. · GT classes clarify Gurney flap wording, replacing wickerbill/tab terminology with flap; specifications unchanged. · TA2 Gurney flap wording clarified: terminology standardized to 'Gurney flap', height limits and thickness specifications remain 0.50 inch / 0.625 inch or 0.375 inch / 0.0625 inch depending on configuration. · STO rear wing wording clarified: 'wicker' changed to 'Gurney flap' in maximum chord and mounting height rules. · GT classes clarify Gurney flap wording, replacing wickerbill/tab terminology with flap; specifications unchanged. · GT2 Dodge Viper 8400 OEM minimum weight drops 50 lbs to 3275. · GT2 Chevrolet Corvette -2019 OEM minimum weight cut 50 lbs to 3275. · Elan NP01 classified in P2 Table 1 as Spec Line car with 2000cc displacement and P2 Engine Table restrictor. · AS Chevrolet/Pontiac Camaro & Firebird (82-92) loses 50 lbs, to 3500. · GT2 Corvette LS6 may reduce weight by 50 lbs. · P2 Enterprises Sports Racer adds 55mm flat plate intake restrictor Part # WM303013 as alternative to SIR. · GT2 Panoz GT-S now allowed to use TA2 Choice Engine with any 5-speed H-pattern transmission. · GT2-ST Corvette LS2 restrictor increases from 70mm to 75mm flat plate. · GT2-ST Corvette L76 added: 5967cc, 3000 lbs minimum, 70mm flat plate restrictor. · P2 Enterprise Sports Racer 2.3L engine now requires SIR or Flat Plate restrictor sized in 0.5mm increments. · GT2 Porsche 991.2 GT3 Cup Car engine displacement increases from 3.8L to 4.0L. · P2 fly-by-wire throttle control wording clarified: stock ECUs with drive-by-wire must activate original throttle shaft mechanism. · AS rear trailing arms may be replaced with tubular arms maintaining stock length and axle location purpose only. · AS Ford and GM full-prep cars get 200 lb weight reduction, up from 150 lb. · 05-10 Ford Mustang Coupe GT 4.6L OHC classified AS with 3200 lbs minimum weight, HR cam restricted prep. · AS 10-15 Chevrolet Camaro Full Prep classified with 3400 lbs base weight, over 313 CID engine 3700 lbs maximum. · GT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications. · GT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications. · GT2 Chevrolet SS replaces Dodge Charger; all stock car bodies removed from GT2 in 2021. · GT2/ST Ford 5.0L Coyote 3rd Gen OEM added at 3200 lbs with Boss intake manifold permitted. · Factory Five Type 65 Coupe R with Ford 302/351 or 5.0/5.2L NA added to GTX-MISC at 2600 lbs. · GT1 sequential shifting transmission weight penalty reduced from 75 to 50 lbs. · GT1 non-18-inch-wheel cars now get 18-inch wheels with 50 lb penalty, down from 100 lb. · GT1 Spec Lines allows 5 Star NASCAR Camaro 2018+ body for General Motors Corporation. · Factory Five Type 65 Coupe R with Ford 302/351 or 5.0/5.2L NA added to GTX-MISC at 2600 lbs. · 991.2 GT3 Cup Car classified in GT2 at 3100 lbs with 63mm throttle body restrictor. · GT2 Acura NSX minimum weight reduced from 3000 to 2700 lbs. · GT2 Porsche 991.1 GT3 Cup restrictor size increases from 67 mm to 70 mm. · GT2 Porsche 996/997.1 GT3 Cup minimum weight reduced 100 lbs, to 2800. · GT2/ST Corvette -2019 5967cc restrictor reduced from 75 mm to 70 mm. · P2 adds BMW to motorcycle-based engine options in 4-cycle line alongside Kawasaki, Suzuki, Yamaha, Honda. · AS Spec Mustang (SMG) added as Restricted Prep class. · P2 Honda K20A-FD2 non-composite chassis must use 55mm flat plate intake restrictor at 1500 lbs minimum weight. · GT1 Porsche 944/968 classified: 2981cc twin turbo, 2585 lbs minimum weight. · P2 motorcycle engines: Stock restrictor 36.5mm to 35mm, modified 37.5mm to 34mm; B.5 restrictor 37.5mm to 33mm. All weights increase 25 lbs. · AS class minimum ride height clarified to 5 inches measured at rocker panel, excluding seams and cladding. · GT1 allows Trans Am rear wing, 12" chord, 72" span, 1/2" wicker, 100 sq in endplates, no weight penalty. · GT2 TA2 cars must weigh minimum 2930 lbs per current Trans Am rules or prior Appendix L. · P2 cars limited to power application on maximum two wheels, effective 2019-07-01. · P2 Enterprise minimum weight increases to 1375 lbs; peak horsepower of sealed ESR engine reduced per CRB specification. · AS Ford Mustang (79-93) 313 CID and under loses 100 lbs to 3150; over 313 CID loses 100 lbs to 3450. · GT2 Toyota Supra 3SGTE newly classified at 2900 lbs minimum weight, 43mm restrictor. · Acura NSX All Years classified to GT2-ST: 3.5L turbo, 3000 lbs minimum, 43mm restrictor. · GT2 TA2 minimum weight increases from 2830 to 2930 pounds. · GTX tube frame cars gain fuel injection with 90mm maximum throttle body size. · Ligier JS2 R classified in GTX, no performance parameters specified in filing. · GT2 BMW E36/E46 4.5L V8 classified at 2950 lbs minimum weight. · GTX tube frame cars gain fuel injection with 90mm maximum throttle body size. · Ligier JS2 R classified in GTX, no performance parameters specified in filing. · GT1 and GT2/GT3/LITE ride height requirements removed from GCR sections 9.1.2.D.5.a.1 and 9.1.2.F.7.b. · GT2 Ford Mustang 5.2L classified at 3300 lbs minimum with 82mm single throttle body restrictor. · GT1 and GT2/GT3/LITE ride height requirements removed from GCR sections 9.1.2.D.5.a.1 and 9.1.2.F.7.b. · GT2 Porsche Cayman model years change from 05-11 to 05-15. · GT2 Porsche Cayman adds 4.0L engine with 65mm flat plate restrictor at 2700 lbs minimum weight. · P2 stock engine restrictor shrinks to 35.0mm and weight rises to 1025 lbs; modified engine restrictor to 34.0mm, weight to 1125 lbs; line B.5 restrictor to 33.0mm, weight to 1185 lbs. · P2 Line A.1 restrictor reduced from 40mm to 38mm. · AS Spec Mustang (SMG) newly classified with 107.1 wheelbase, 3.73 gears, 355mm front brakes, 300mm rear. · GTX FIA GT3: Audi R8 40mm restrictor 2900 lbs, BMW Z4 70mm 2800 lbs, Ferrari 488 35mm restrictor 3025 lbs classified. · GT2 BMW E46 M3, E36, Z3, and 5000cc V8 now permit Flossman body kit. · GT2 TA2 cars: wheels cost cap drops to $175 each, carbon fiber allowed on rear wing, engine setback maximum 21.75 inches (A-F) or 24 inches (G), various nomenclature and clarification updates. · BMW 1 Series E82 classified into GT2 with N52B30 engine, 2996 cc, 2140 lbs minimum weight. · GT2 Porsche Cayman 05-11 base weight drops 75 lbs to 2800; adds STO/X51 motor notes. · GT2 Ford Mustang 05- with 5.2L Aluminator engine classified: 3400 lbs minimum weight, 2×41mm flat plate restrictor. · GT2 Porsche 996/997.1 GT3 Cup adds 3.6L displacement and 2900 lbs minimum weight; removes aftermarket exhaust header allowance for 996. · GT2 Ford Mustang FP350S minimum weight reduced 100 lbs, to 3400. · GT2 Ford Mustang 05- EcoBoost classified: 3500cc, 3200 lbs minimum, 41mm restrictor. · GT2 Mazda RX7 Downing GTS body kit allowed without 75 lbs. weight penalty. · GTX FIA GT3: Audi R8 40mm restrictor 2900 lbs, BMW Z4 70mm 2800 lbs, Ferrari 488 35mm restrictor 3025 lbs classified. · P2 Spec Line cars now allow 1345cc Hayabusa stock engines at 1050 lbs with 30mm restrictor. · P2 Group CN Honda K20A-FD2 55mm restrictor implementation delayed from 1/1/2019 to 3/1/2019. · P2 Honda K20A-FD2 in CN chassis must use stock intake manifold with 64mm throttle body and 55mm restrictor at 1500 lbs minimum weight.showhide
GT1 Sequential Transmission Weight Penalty #33503weightfasterGT1 sequential transmission weight penalty reduced from 50 to 25 lbs.
GT1 GT1 Porsche 992 #33730cars addedneutralGT1-ST Porsche 992 GT3 Cup classified with 3997cc displacement, 2950 lbs minimum weight.
GT2 GT2 Mazda 13B Turbo #33729engineunclearGT2 Mazda 13B Street Port turbo changes from EFR 76/70 to BW7670 or Garrett G30-660 with 46mm TIR at 2280 lbs.
GT2 Request Permission to Use a Substitute Turbo #33337inductionfasterGT2 Porsche SOHC 2478/2681/2992 turbo sizes increase from 42mm to 44mm SIR to TIR.
GT2 Request to Reduce Restriction on C7 GT2 Corvette #33342inductionfasterGT2-ST Chevrolet Corvette 14-19 L76 5967 restrictor increases from 70 to 73 mm.
GT2 Toyota 4A-F and 4A-FE 1.6L DOHC 16V Engine Request #33415cars addedneutralGT2 Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines newly classified in spec line.
GT2 GT2 Mazda 13b turbocharger part # update #33437enginefasterGT2 Mazda 13B Street/Bridge Port turbocharger changes from EFR 70/76 to 76/70, compressor from 42mm to 46mm.
GT2 GT2-ST BMW E36/46 spec line remove #33610wordingneutralGT2-ST BMW E36/46 spec line adds MA Shaw carbon/composite door offerings to Notes.
GT2 GT3 Choke option effective 1-01-2023 #33669inductionneutralGT3 normally aspirated cars may use intake chokes instead of SIRs, fitted to each carburetor barrel, same size as required SIR.
GT2 GT3 2.0L choke/weight option #33670inductionfasterGT3 2.0L 4-valve non-turbo engines may run unrestricted at 2060 lbs instead of with a choke restriction.
P2 Request to Classify Sebeco NP01 #33378cars addedneutralSebeco NP01-EVO and Elan NP01 Mazda 2.0L MZR added to P2, 1600 lb minimum, no restrictor required.
P2 Radical spec line clarifications #33485wordingneutralP2 Radical SR3/SR4/Cup/Club Sport/Pro-Sport/PR6 removes assisted shifting requirement across all spec lines.
P2 E&O original class intent #33519wordingneutralP2 chassis rules clarified to allow composite materials in non-fully-composite construction; anti-intrusion panel attachment standardized; Stohr and converted F600 cars added with specific allowances.
P2 Update Engine Table Spec Line B.1 #33608engineunclearUnable to summarize: the change to P2 Engine Table Spec Line B.1 is not detailed in the provided text.
GT1 GT2 (TA2)/GTA Part Number Update #33315wordingneutralGT2 TA2 and GTA throttle body part numbers updated to GM 90mm electronic #12570790 or Edelbrock 90mm mechanical #33869 or #3870.
GT1 Request to Reduce Trans Am Bodywork Weight Penalty #33331weightfasterGT1 Trans Am bodywork weight penalty reduced from 100 lbs to 75 lbs.
GT1 Request for Reduction in FR9 Weight Penalty #33332weightfasterGT1 Chevrolet RO7, Ford FR9, and Dodge R7 weight penalties reduced from 50 to 25 lbs.
GT2 GT2 (TA2)/GTA Part Number Update #33315wordingneutralGT2 TA2 and GTA throttle body part numbers updated to GM 90mm electronic #12570790 or Edelbrock 90mm mechanical #33869 or #3870.
GT2 Ginetta G56 GTA - Optional Wheels #33357tyres & wheelsneutralGT2 Ginetta G56 GTA gains optional 18" x 9" and 18" x 10" wheels.
GT2 Allow the MAShaw Body Kit on the GT2/ST Spec Line for BMW E36/E46 #32447aerofasterGT2/ST BMW E36/E46 now allows MAShaw body kit parts: wide body, bumpers, fenders, rockers, flairs.
GT2 Request for C5/C6 Corvette Restrictor Size Review #32982inductionfasterGT2 Chevrolet Corvette L76 5967 restrictor increases from 73mm to 74mm.
AS Request to add Hoosier W2 #33031tyres & wheelsneutralAS allows Hoosier W2 tyre option in addition to R7, R6, WET/H20.
AS correction of Dodge Challenger specification line #33151wordingneutralAS Dodge Challenger 08-20 adds two transmission ratio options: 2.97, 2.10, 1.45, 1.00, 0.74, 0.50 or 2.26, 1.58, 1.19, 1.00, 0.77, 0.63.
GT1 Tail lights on all GT category race cars. #32799wordingneutralGT taillights may now be original style or a panel graphic with functioning red LED brake lamps; wording change only.
GT2 Tail lights on all GT category race cars. #32799wordingneutralGT taillights may now be original style or a panel graphic with functioning red LED brake lamps; wording change only.
GT2 Addendum to letter #32514 Ginetta GTA G56 #33076cars addedneutralGinetta GTA G56 added to GT2 as spec car: 2600 lbs, 3.7L Ford V6 sealed, 6-speed Quaife sequential.
GT2 Information requested for carbon roofs on BMW E36/E46 cars in GT2 #32682wordingneutralGT2 BMW E36/E46 carbon roof and door suppliers added to notes: Lang Racing, 2M Automotive, Flossmann, MA Shaw.
GT2 Request to Allow the 95mm S54 BMW Crankshaft in GT2-ST #32698weightslowerGT2-ST BMW E46 M3, E36, Z3, 5000cc V8 can use 95mm S54 crankshaft at +150 lbs.
GT2 Request to classify Audi R8 FIA GT4 to GT2 #32805cars addedneutralAudi R8 GT4 classified to GT2 with 5.2L displacement, 3000 lbs minimum weight, per factory specs restrictor.
AS Request CTS-V Spec Line Error Correction #30242weightfasterAS Cadillac CTS-V 6.0L V8 removes 50 lbs weight penalty for 295 tire size.
GT2 Typo in rules for shocks #32308wordingneutralGT2 shock absorber attachment points clarified as moveable; wording correction only.
GT2 additional response to letters #31898 & 32083 #32424weight +140 lbsslowerGT2 Porsche 104.0 x 88.0 engine weight increases from 1950 to 2090 lbs; 2V variants may use Borg Warner EFR 76/70 42mm turbo.
P2 E&O Clarification of Chassis Construction Requirements #32469wordingneutralP2 chassis construction rules clarified: fully composite or partially composite requiring composite for mobility allowed; partial composite must roll without composite parts.
P2 Clean up P2 wording #32525wordingneutralP2 classification wording cleaned up in GCR section 9.1.8.C and Contents.
P2 After Market to Aftermarket #32373wordingneutralP2 Oldsmobile cam rules clarify aftermarket manufacturer requirements; wording only.
GT1 Mercedes Benz AMG GT3 in GT1 #31883cars addedneutralMercedes Benz AMG GT3 classified in GT1 at 3050 lbs with 40mm restrictors, prepared per FIA GT3 homologation.
GT1 Wheel Widths #32205tyres & wheelsfasterGT1 wheels: 18-inch tyres get wider rear allowance, from 13 to 14 MAX inches.
GT2 Request to Classify Ginetta G40 in GT2 #31597cars addedneutralGinetta G40 classified in GT2 with Mazda MZR/L5-VE engine, 2488cc or 2399cc, 1950 lbs base weight.
GT2 2021 Supra GR GT4 #31737cars addedneutralToyota Supra GT4 added to GT2-ST: 3000cc, 3000 lbs minimum, factory restrictor.
GT2 Proposed Technical Bulletin #31900wordingunclearGT2 Porsche 944/924 may use ERC 76/70 Turbo instead of Jayco super 50.
P2 Add spec line for Beasley B2 #32147cars addedneutralP2 adds Beasley B2 spec line with 1350 lbs, Mazda 12A, 40.5mm venturi, 16.5in wing.
P2 E&O Table 1 spec line wing terminology #32148wordingneutralP2 wing specs correct terminology from 'cord' to 'chord' for 16.5in single or dual element wings.
P2 E&O class name #32196wordingneutralP2 Converted F5 cars reclassified as Converted F500 cars; suspension must comply with F500 requirements, minimum width 55 inches.
GT1 Wheel Widths #31844tyres & wheelsslowerGT1 allows 17-inch wheels newly; 18-inch wheels require 50 lb penalty; maximum widths 12 front/13 rear, or 13/14 for 18-inch.
GT2 GT2/ST Porsche Cayman #31451 correct TBR size error #31991enginefasterGT2 Porsche Cayman 05-15 turbo restrictor increases from 70mm to 75mm.
P2 E&O Engine section #31969enginefasterP2 motorcycle engines increase to 1505cc max, two-stroke to 1205cc max; automotive engines gain 50 lbs minimum weight to 1350.
AS Proposed Revisions to SCCA GCR 2021 Appendix M, Part 3 #30295wordingneutralSMG long tube headers: Borla PN 17237 discontinued, Kooks PN 11312000 and American Racing PN MT3-05134300LSNC approved alternatives.
AS specification line consolidation and correction #31846wordingneutralAS Mercury Capri (79-86) removed as individual spec line, merged into Ford Mustang (79-93) spec line.
AS correction of SMG specification line #31847wordingunclearAS Spec Mustang SMG loses 3.73 gear ratio and 355/300 mm brake specification.
AS Alternate cylinder heads for full prep engine builds - Evaluation #31851engineunclearAS Chevrolet, Pontiac, Ford full prep engines now permit alternate cylinder heads with restrictor plate ALL26180 and 1.250 inserts ALL26186 for regional competition.
GT2 Restrictor Clarification for 2015 Cayman #31451wordingunclearGT2 Porsche Cayman 05-15 uses Throttle Body Restrictor instead of Flat Plate Restrictor at 2700 lbs.
P2 E&O letter #31539 – Control Area definition #31783aeroslowerP2 Control Area definition narrowed; aerodynamic attachments and vertical structures like turning vanes now prohibited.
P2 BoP adjustment effective 1-1-22 #31538wordingunclearP2 Engine Table Spec Line B.1 changed effective 1-1-22, details not provided in excerpt.
P2 E&O clarification of "Control Area" definition #31539wordingneutralP2 Control Area definition clarified: floor extensions and aerodynamic attachments on bottom or top side now explicitly included.
AS Request for adjustable Front Upper Control Arms on 4th Gen F-Body #30457suspension & brakesneutralAS Chevrolet/Pontiac Camaro & Firebird 93-02 now allow BMR AA004 or UMI 2310 adjustable front upper control arms.
AS Request Pontiac GTO tire size change #30881weightslowerAS Pontiac GTO 04-06 LS1 to 3300 lbs, LS2 to 3350 lbs on 295 tire.
GT1 Request car classification #31032cars addedneutralGT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight.
GT2 Turbo Request for 13B Engine #30656engineunclearGT2 Mazda 13B street port adds EFR 70/76 turbo with 42mm restrictor at 2280 lbs.
GT2 Request car classification #31032cars addedneutralGT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight.
GT2 Correct letter 30565 GT2/ST #31088weightfasterGT2 Dodge Viper Comp Coupe ACR/ACR-X loses 100 lbs minimum weight to 3275.
P2 P2 CN Engine Rebuild Clarification #31000wordingneutralP2 CN Honda K20A-FD2 engine rebuild rules clarified: machining prohibition replaced with specific restrictions on balancing, porting, polishing, valve jobs, cylinder honing.
GT1 Request to Update GTA Obsolete Part Numbers #30615wordingneutralGTA part numbers updated: 0-80541-1 to 0-80541-2 in two sections and 6010 to 6014X in TA2 Appendix.
GT2 Request the 04-06 Pontiac GTO WC Car Be Added to the GT2/ST Chart #30339cars addedneutral04-06 World Challenge Pontiac GTO added to GT2-ST: 6062 cc, 3000 lbs minimum, unrestricted.
GT2 Request to Update GTA Obsolete Part Numbers #30615wordingneutralGTA part numbers updated: 0-80541-1 to 0-80541-2 in two sections and 6010 to 6014X in TA2 Appendix.
GT2 GTX class correction to GT2/ST #30973cars addedneutralGrullon GT with 2.0L K20 moved from GTX to GT2-ST, minimum weight 2350 lbs, unrestricted.
P2 F5 P2 Conversion #30856aerofasterConverted F5 cars in P2 minimum width reduced to 55 inches from F5 spec.
P2 Clarify minimum body width requirement #30859wordingneutralP2 clarifies minimum body width requirement between front and rear wheels for Ralt RT40, RT41, Swift 008, 014.
GT2 Porsche Cayman Engine Modification and Engine Request #30472inductionfasterGT2-ST Porsche Cayman restrictor increases from 65mm to 75mm flat plate at 2700 lbs.
GT2 Request weight clarification Viper CC #30565weightfasterGT2 Dodge Viper including Comp Coupe, ACR/ACR-X minimum weight reduced 100 lbs to 3275 in VRL Spec.
GT2 Variance, 2021 TA2 Rules vs GCR Appendix L #30641wordingneutralTA2 minimum weight set to 2930 lbs with free tire make and size.
AS Request CTS-V Spec Line Error Correction #30242weightfasterAS Cadillac CTS-V 6.0L V8 removes 50 lbs tire size penalty, making it lighter.
AS Request to consolidate SN95 Mustang '94-'04 Mustang spec lines #30428wordingneutralAS consolidates seven SN95 Mustang spec lines into three: 94-04 including Cobra, 94-95 5.0/5.8, and 96-04 4.6L two/four valve.
AS American Sedan Transmission Rule Change Request #30595enginefasterAS Camaro/Firebird LT1/LS1 transmission code changes to 6362; Mustang GT 4.6L/5spd changes to 5.0L/6spd with 300 lbs weight reduction.
AS Correction to specifications inadvertently deleted #30691wordingneutralAS Camaro/Firebird and Mustang GT gear ratio specifications restored with alternate sets permitted.
AS weight adjustments #30700weight +50 lbsslowerAS Chevrolet Camaro & Firebird, Ford Mustang variants, Mercury Capri minimum weights increase 50 lbs across all model years.
P2 E&O tonneau cover provision in cockpit opening section #30459wordingneutralP2 tonneau covers now allowed to meet minimum dimensions; equipment attachment requirements clarified.
P2 Remove effective dates in Table 1 #30468wordingneutralP2 multiple chassis models remove effective dates from Table 1 specifications.
P2 E&O Maximum Valves Per Cylinder #30560engineneutralP2 engines limited to 4 valves per cylinder maximum across all three spec lines.
GT2 GT2 tiger firing order #30421wordingneutralGT2 Sunbeam SBF 302 engine firing order option now explicitly allows Boss 302 variant.
AS AS Mustang LP 4.6 3V Classification Transmission Request #29886weightfasterAS Mustang 4.6L/5spd loses 300 lbs; 5.0L/6spd gains 56mm restrictor requirement.
AS Request CF driveshaft on CTS-V for durability improvement #30117otherneutralAS CTS-V LS6 and LS2 may now use Driveshaft Shop carbon fiber driveshaft for durability.
AS Adjustment to model years of 5th generation RP Camaro #30348wordingneutralAS Chevrolet Camaro SS V8 6.2L model years extended from 10-13 to 10-15.
GT2 GT2-ST CORVETTE CHANGES #30029weight +100 lbsslowerGT2-ST Corvette (-2019) LS2 and L76 5967cc gain 100 lbs minimum weight to 3100; 6162cc variants gain 50–100 lbs; 7011 gains 100–50 lbs; L76 restrictor opens 70 to 73 mm.
GT2 29742 Change new wording to read as: #30329wordingneutralGT2 Ford Mustang/Thunderbird Boss 302 firing order now optional from later SBF 302 versions.
P2 Add a new spec line for a 2-cycle, 3-cylinder engine up to 820cc #30272cars addedneutralP2 adds new spec line for 2-cycle 3-cylinder engine up to 820cc with 10 front and 14-15 rear wheel width.
GT2 ABS Restrictions #30064wordingneutralGT2 ABS braking systems now allowed if shown on individual Spec Line.
AS Request for 2015 -2017 Ford Mustang Spec Line #29514cars addedneutralFord Mustang GT 5.0L 15-17 Restricted Preparation classified in AS with 55mm flat plate restrictor required.
AS Request Trunk lid / Rear Hatch clarification #29591wordingneutralAS underhood bracing on stock hoods, trunks, and rear decks may be modified or removed.
AS Common Weight for CTS-V Tire #29759weightfasterAS Cadillac CTS-V 04-07 with 295 tire drops to 3450 lbs; Camaro SS V8 10-13 275 tire removed; Challenger 08-20 gains 315 tire option at 3600 lbs.
AS Correction to specifications inadvertently deleted #30041weightfasterAS Camaro & Firebird (93-02) and Mustang GT (05-14) specifications restored with 200 lb weight reduction for permitted heads.
GT2 Request change to engine firing order rule #29742engineunclearGT2 Ford Mustang/Thunderbird Boss 302 firing order becomes unrestricted.
GT2 Request E-46 BMW M3 balance of performance #29833weight -100 lbsfasterGT2 BMW E46 M3 weight reduced from 2600 to 2500 lbs.
AS Request Additional Engine Options for Dodge Challenger Spec Line #29543engineslowerAS Dodge Challenger 08-20 gains 6.1L and 6.4L V8 options; 5.7L weight rises to 3500 lbs on 295 tyres, 3600 on 315 tyres.
AS Rule simplification spec line communization #29824wordingfasterAS Camaro/Firebird (93-02) and Mustang Coupe GT (05-14) consolidated into single specs with 100 lb and 300 lb weight reductions respectively.
GT2 Request for Bigger Engine in Plymouth Breeze #29380cars addedneutralGT2 Chrysler/Dodge/Plymouth 2429cc DOHC engine classified at 1950 lbs, unrestricted fuel induction.
P2 Balance of Performance adjustments effective 01-01-2021 #29822inductionfasterP2 Honda K20A-FD2 intake restrictor reduced from 55mm to 50mm, making cars faster.
GT2 rescind GT2 stock car bodies removal #29219cars addedfasterGT2 stock car bodies removal rescinded; 1997-current year commercially available stock car bodies remain allowed.
GT2 E&O Typos in Appendix L #29447wordingneutralGT2 Appendix L renumbering eliminates sections .17 through .19 after 4.8.4.2.10.3.6.
GT2 GT2 wing width wording correction #29469wordingneutralGT2 TA2 wing width maximum set to 65 -5/16 inches, previously undefined.
GT1 GT Category Wording #29193wordingunclearGT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line.
GT2 GT Category Wording #29193wordingunclearGT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line.
GT2 Corvette GT2-ST intake manifold #29221wordingneutralGT2 Chevrolet Corvette -2019 LS1/LS6 allows DORMAN part # 615-900 alternate intake manifold.
GT2 997.2 E&O link to 27915 #29373weightfasterGT2 Porsche 997.2 GT3 Cup minimum weight drops to 2900 lbs.
P2 E&O clarification of P2 rear wing requirements #29205aeroneutralP2 rear wing requirements clarified: standard wing 6×12 inches, end plates 14-inch square; alternate 110cm width wing 9×18 inches, end plates 14×18 inches.
AS Dodge Challenger AS Spec Line Clarification #28698engineslowerAS Dodge Challenger 5.7L V8 gets iron block requirement, 10.5:1 compression max, intake valve 12.7 mm, exhaust 12.3 mm, intake duration 188°, exhaust duration 205°.
AS Dodge Challenger AS Spec Line Clarification #2 #28699wordingneutralAS Dodge Challenger 08-14 rear spoiler part number changes from 1GL20RXF to 1GL20TZZAB.
GT1 Request to Allow New Trans Am Legal Engines in GT1 #29002engineslowerGT1 adds Trans Am spec engines: Chevrolet R07, Ford FR9, Dodge R7, each with 50 lbs. weight penalty.
GT2 Request for allowance Trans Am SGT #28951wordingneutralGT2 BMW E46 M3, E36, Z3, and 5000cc V8 gain Trans Am SGT spec allowance: regular shifter 3000 lbs., paddle shifter plus 150 lbs.
GT2 Omitted GT2 fender/hood openings #29171aeroneutralGT2 allows up to four hood/fender louvered panels, max 600 sq inches total, min five slots each, mounted in front of windscreen.
AS Support for R-Type Specification Tires #27450tyres & wheelsunclearAS class pursues specified list of eligible tires; details of tire changes not provided in letter.
AS Spec Tire Request #27519tyres & wheelsunclearAS class pursuing specified list of eligible tires; details pending further communication.
AS Restrictor Plate Change for RP 2011+ Mustang with Coyote Engine #27675wordingunclearNo restrictor plate change implemented; 2021 AS Mustang Coyote under evaluation.
AS 2005-2009 Restricted Prep 4.6 3V #27908engineunclearAS 2005-2009 Restricted Prep 4.6 3V now permits conversion to 2 valve configuration.
AS Request for 2005-2009 Restricted Prep 4.6 3V Parts #27909wordingunclearAS Ford Mustang Coupe GT 4.6L 3V Restricted Prep now permits Ford Performance camshaft kit P/N-M-6550-3V.
AS Request for Full Preparation Classification for 2010-2014 Camaro #28030cars addedunclear2010-2014 Camaro reclassified to AS; full preparation classification approved effective 2020-07-01.
AS Cylinder Heads #28696wordingunclearAS class cylinder head replacement options under review; implementation planned for 2021 season.
AS Request for Max Rotor Diameter Change #28748suspension & brakesfasterAS Mustang, Camaro, Firebird, Capri max brake rotor diameter increases from 12.2 to 13.1 inches.
AS Request increase rotor diameter #28797suspension & brakesneutralAS rotor diameter increase approved; see Fastrack letter #28748 for details.
GT1 TA2 Gurney flap wicker clarification #28874wordingneutralTA2 Gurney flap wording clarified: terminology standardized to 'Gurney flap', height limits and thickness specifications remain 0.50 inch / 0.625 inch or 0.375 inch / 0.0625 inch depending on configuration.
GT1 STO Gurney flap wicker clarification #28883wordingneutralSTO rear wing wording clarified: 'wicker' changed to 'Gurney flap' in maximum chord and mounting height rules.
GT1 GT1 Gurney flap wicker clarification #28886wordingneutralGT1 Gurney flap wicker clarification: terminology standardized from lips/tabs/wicker to flaps throughout specifications.
GT2 TA2 Gurney flap wicker clarification #28874wordingneutralTA2 Gurney flap wording clarified: terminology standardized to 'Gurney flap', height limits and thickness specifications remain 0.50 inch / 0.625 inch or 0.375 inch / 0.0625 inch depending on configuration.
GT2 STO Gurney flap wicker clarification #28883wordingneutralSTO rear wing wording clarified: 'wicker' changed to 'Gurney flap' in maximum chord and mounting height rules.
GT2 Request to Adjust Weight of OEM 8.4 Viper #28739weight -50 lbsfasterGT2 Dodge Viper 8400 OEM minimum weight drops 50 lbs to 3275.
GT2 Request to Adjust Weight of OEM Chevrolet Corvette #28896weight -50 lbsfasterGT2 Chevrolet Corvette -2019 OEM minimum weight cut 50 lbs to 3275.
P2 Classify Elan NP01 in P2 Table 1 #28812cars addedneutralElan NP01 classified in P2 Table 1 as Spec Line car with 2000cc displacement and P2 Engine Table restrictor.
AS weight adjustments for 2020 season #28785weight -50 lbsfasterAS Chevrolet/Pontiac Camaro & Firebird (82-92) loses 50 lbs, to 3500.
GT2 Request Corvette engine parity #28576weightfasterGT2 Corvette LS6 may reduce weight by 50 lbs.
P2 SCCA Enterprises ESR / P2 engine restrictor testing #28669engineneutralP2 Enterprises Sports Racer adds 55mm flat plate intake restrictor Part # WM303013 as alternative to SIR.
GT2 Request to revisit Panoz GT-S BoP #28280wordingunclearGT2 Panoz GT-S now allowed to use TA2 Choice Engine with any 5-speed H-pattern transmission.
GT2 GT2-ST Corvette LS2 & L76 #28583inductionfasterGT2-ST Corvette LS2 restrictor increases from 70mm to 75mm flat plate.
P2 Add ESR inlet restrictor #27869inductionslowerP2 Enterprise Sports Racer 2.3L engine now requires SIR or Flat Plate restrictor sized in 0.5mm increments.
GT2 Request 991.2 Porsche engine displacement verify typo #28194enginefasterGT2 Porsche 991.2 GT3 Cup Car engine displacement increases from 3.8L to 4.0L.
P2 Request for Fly by Wire Rule Wording Change #28247wordingneutralP2 fly-by-wire throttle control wording clarified: stock ECUs with drive-by-wire must activate original throttle shaft mechanism.
AS Rear Trailing Arms #28007suspension & brakesneutralAS rear trailing arms may be replaced with tubular arms maintaining stock length and axle location purpose only.
AS Weight reduction for cars running iron heads #28010weightfasterAS Ford and GM full-prep cars get 200 lb weight reduction, up from 150 lb.
AS 05-10 Mustang with HR cam classification #28226cars addedneutral05-10 Ford Mustang Coupe GT 4.6L OHC classified AS with 3200 lbs minimum weight, HR cam restricted prep.
AS 10-15 Camaro Full Prep classification #28227cars addedneutralAS 10-15 Chevrolet Camaro Full Prep classified with 3400 lbs base weight, over 313 CID engine 3700 lbs maximum.
GT1 Windshield Clips #27323wordingneutralGT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications.
GT2 Windshield Clips #27323wordingneutralGT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications.
GT2 Request to Add Chevrolet SS Body to Appendix L #27898cars addedneutralGT2 Chevrolet SS replaces Dodge Charger; all stock car bodies removed from GT2 in 2021.
GT1 Request to classify the Ford Coyote 3rd Gen OEM #27146cars addedneutralGT2/ST Ford 5.0L Coyote 3rd Gen OEM added at 3200 lbs with Boss intake manifold permitted.
GT1 Request Factory Five Daytona coupe classification #26308cars addedneutralFactory Five Type 65 Coupe R with Ford 302/351 or 5.0/5.2L NA added to GTX-MISC at 2600 lbs.
GT1 Request to Adjust Transmission Penalty #27750weightfasterGT1 sequential shifting transmission weight penalty reduced from 75 to 50 lbs.
GT1 Request to Reduce Additional Weight for 18 #27751weightfasterGT1 non-18-inch-wheel cars now get 18-inch wheels with 50 lb penalty, down from 100 lb.
GT1 Request for Five Star Nascar Compliant Bodywork #27756cars addedneutralGT1 Spec Lines allows 5 Star NASCAR Camaro 2018+ body for General Motors Corporation.
GT2 Request Factory Five Daytona coupe classification #26308cars addedneutralFactory Five Type 65 Coupe R with Ford 302/351 or 5.0/5.2L NA added to GTX-MISC at 2600 lbs.
GT2 Porsche 991.2 GT3 Cup GT2 Classification #27701cars addedneutral991.2 GT3 Cup Car classified in GT2 at 3100 lbs with 63mm throttle body restrictor.
GT2 Request for Acura NSX Spec Line Changes #27755weightfasterGT2 Acura NSX minimum weight reduced from 3000 to 2700 lbs.
GT2 GT2 991.1 restrictor size change #27914inductionfasterGT2 Porsche 991.1 GT3 Cup restrictor size increases from 67 mm to 70 mm.
GT2 GT2 996/997.1 weight change #27915weight -100 lbsfasterGT2 Porsche 996/997.1 GT3 Cup minimum weight reduced 100 lbs, to 2800.
GT2 GT2/ST Corvette comp adjustment #27920inductionslowerGT2/ST Corvette -2019 5967cc restrictor reduced from 75 mm to 70 mm.
P2 Request for addition of BMW Engine in P2 Engine Table #27821cars addedneutralP2 adds BMW to motorcycle-based engine options in 4-cycle line alongside Kawasaki, Suzuki, Yamaha, Honda.
AS Request to add SMG to 9.1.6.B.1 AS Intent #27140cars addedneutralAS Spec Mustang (SMG) added as Restricted Prep class.
P2 Update Engine Table Line E notes #27414inductionslowerP2 Honda K20A-FD2 non-composite chassis must use 55mm flat plate intake restrictor at 1500 lbs minimum weight.
P2 Update P2 Engine Table spec lines to reflect 3/1/2019 #27254inductionslowerP2 motorcycle engines: Stock restrictor 36.5mm to 35mm, modified 37.5mm to 34mm; B.5 restrictor 37.5mm to 33mm. All weights increase 25 lbs.
AS Request Ride Height Clarification #26598wordingneutralAS class minimum ride height clarified to 5 inches measured at rocker panel, excluding seams and cladding.
GT1 Clarify Trans Am Legal Bodywork and Wing #26953aerofasterGT1 allows Trans Am rear wing, 12" chord, 72" span, 1/2" wicker, 100 sq in endplates, no weight penalty.
GT2 TA2 Weight Clarification #27077weightslowerGT2 TA2 cars must weigh minimum 2930 lbs per current Trans Am rules or prior Appendix L.
P2 E&O Transmissions #27006otherslowerP2 cars limited to power application on maximum two wheels, effective 2019-07-01.
P2 Request to restrict all cars #26246weightslowerP2 Enterprise minimum weight increases to 1375 lbs; peak horsepower of sealed ESR engine reduced per CRB specification.
AS Request to Revert to 2017 Weights #25885weightfasterAS Ford Mustang (79-93) 313 CID and under loses 100 lbs to 3150; over 313 CID loses 100 lbs to 3450.
GT2 Request to classify Toyota Supra with 3SGTE engine #25185cars addedneutralGT2 Toyota Supra 3SGTE newly classified at 2900 lbs minimum weight, 43mm restrictor.
GT2 Request to Classify Acura NSX from T1 to GT2? #26121cars addedneutralAcura NSX All Years classified to GT2-ST: 3.5L turbo, 3000 lbs minimum, 43mm restrictor.
GT2 Request for TA2 BOP in GT2 #26509weightslowerGT2 TA2 minimum weight increases from 2830 to 2930 pounds.
GT1 Request GTX Fuel injection for previous GT-1 tube frame cars #26141inductionfasterGTX tube frame cars gain fuel injection with 90mm maximum throttle body size.
GT1 Request to Classify Ligier JS2 R #26535cars addedneutralLigier JS2 R classified in GTX, no performance parameters specified in filing.
GT2 Request for e36/e46 bmw 4500 cc v8 at 2950lbs in GT2/ST #26106cars addedneutralGT2 BMW E36/E46 4.5L V8 classified at 2950 lbs minimum weight.
GT2 Request GTX Fuel injection for previous GT-1 tube frame cars #26141inductionfasterGTX tube frame cars gain fuel injection with 90mm maximum throttle body size.
GT2 Request to Classify Ligier JS2 R #26535cars addedneutralLigier JS2 R classified in GTX, no performance parameters specified in filing.
GT1 Request Ride Height Clarification #26600wordingneutralGT1 and GT2/GT3/LITE ride height requirements removed from GCR sections 9.1.2.D.5.a.1 and 9.1.2.F.7.b.
GT2 Request Ford Perfomance 5.2L crate engine FPR clarification #26159cars addedneutralGT2 Ford Mustang 5.2L classified at 3300 lbs minimum with 82mm single throttle body restrictor.
GT2 Request Ride Height Clarification #26600wordingneutralGT1 and GT2/GT3/LITE ride height requirements removed from GCR sections 9.1.2.D.5.a.1 and 9.1.2.F.7.b.
GT2 Request Porsche Cayman year classification #26241wordingneutralGT2 Porsche Cayman model years change from 05-11 to 05-15.
P2 Change Engine Table Lines B.1 & B.5 #25777inductionslowerP2 stock engine restrictor shrinks to 35.0mm and weight rises to 1025 lbs; modified engine restrictor to 34.0mm, weight to 1125 lbs; line B.5 restrictor to 33.0mm, weight to 1185 lbs.
P2 Change Line A.1 restrictor size #26429inductionslowerP2 Line A.1 restrictor reduced from 40mm to 38mm.
AS SMG Mustang eligibility in American sedan #26224cars addedneutralAS Spec Mustang (SMG) newly classified with 107.1 wheelbase, 3.73 gears, 355mm front brakes, 300mm rear.
GT1 GTX Homologation table update #26034cars addedneutralGTX FIA GT3: Audi R8 40mm restrictor 2900 lbs, BMW Z4 70mm 2800 lbs, Ferrari 488 35mm restrictor 3025 lbs classified.
GT2 ST/GT2 BMW Flossman Kit Clarification #22138wordingunclearGT2 BMW E46 M3, E36, Z3, and 5000cc V8 now permit Flossman body kit.
GT2 Request Clarification/Revision of Appendix L (2013 TA2 Rules) #25110otherfasterGT2 TA2 cars: wheels cost cap drops to $175 each, carbon fiber allowed on rear wing, engine setback maximum 21.75 inches (A-F) or 24 inches (G), various nomenclature and clarification updates.
GT2 Request to classify BMW E82 (1 series) into GT2 #25539cars addedneutralBMW 1 Series E82 classified into GT2 with N52B30 engine, 2996 cc, 2140 lbs minimum weight.
GT2 2010 Cayman Street Tuner Into an STO Car,Addendum #25545weightfasterGT2 Porsche Cayman 05-11 base weight drops 75 lbs to 2800; adds STO/X51 motor notes.
GT2 Request - Classify Ford Performance 5.2l #25716cars addedneutralGT2 Ford Mustang 05- with 5.2L Aluminator engine classified: 3400 lbs minimum weight, 2×41mm flat plate restrictor.
GT2 Add missing displacement, minimum weight. Remove #25765wordingneutralGT2 Porsche 996/997.1 GT3 Cup adds 3.6L displacement and 2900 lbs minimum weight; removes aftermarket exhaust header allowance for 996.
GT2 Request for Ford FP 350s Weight Reduction #25806weightfasterGT2 Ford Mustang FP350S minimum weight reduced 100 lbs, to 3400.
GT2 Request to Classify EcoBoost Mustang #25842cars addedneutralGT2 Ford Mustang 05- EcoBoost classified: 3500cc, 3200 lbs minimum, 41mm restrictor.
GT2 Request to Remove Mazda RX 7 Body Work Penalty #26024weightfasterGT2 Mazda RX7 Downing GTS body kit allowed without 75 lbs. weight penalty.
GT2 GTX Homologation table update #26034cars addedneutralGTX FIA GT3: Audi R8 40mm restrictor 2900 lbs, BMW Z4 70mm 2800 lbs, Ferrari 488 35mm restrictor 3025 lbs classified.
P2 Request to Allow 1345cc Hayabusa Engines for Spec Line P2 Cars #25595enginefasterP2 Spec Line cars now allow 1345cc Hayabusa stock engines at 1050 lbs with 30mm restrictor.
P2 Change CN inlet restrictor implementation date #25816wordingneutralP2 Group CN Honda K20A-FD2 55mm restrictor implementation delayed from 1/1/2019 to 3/1/2019.
P2 Clarify Honda K20A-FD2 parts requirement #25950inductionslowerP2 Honda K20A-FD2 in CN chassis must use stock intake manifold with 64mm throttle body and 55mm restrictor at 1500 lbs minimum weight.
Best is the class's fastest lap in that event's qualifying or race sessions, with the driver who set it, how many cars set a time that session and how close the top five were; a best from fewer than three cars is greyed. With two or more classes, "vs" is the gap of each class's best to the first class's at the same event. "% of GT2" is the class's best as a share of GT2's best at the same event (100% is level, less is quicker): weather and track condition move every class together, so this compares across years where the raw times do not. It still breaks when GT2's own field changes or one session was wet and another dry. Newest event first. The coloured figure under each value is the change from the previous event that has one (green is quicker, red slower). Whole laps only, so events with different sector layouts still compare. Weather and track condition are not accounted for.