Lap times across years say as much about the weather as the class. % of GT2 is each class's best lap as a share of GT2's on the same day, so the conditions drop out: 100% is level, less is quicker, and a move in it is the class getting faster or slower against the field.
Quickest here:GT2 1:25.405 Andrew Aquilante, Runoffs 2016 qualifying · SM 1:40.514 Justin Hille, Runoffs 2016 qualifying · T3 1:10.656 Mark Drennan, Runoffs 2018 qualifying
GT2SMT3solid race · dashed qualifying · slower is lower
GT2SMT3solid 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, less is quicker, so up the chart is quicker
2:09.634John Atwell · fastest of 18 · top 5 within 4.3s-2.173s (-1.65%)
2:10.650John Atwell · fastest of 18 · top 5 within 4.1s-2.797s (-2.10%)
163.0Jack Stanford-0.3 mph (-0.2%)
2:42.173Brett Kowalski · fastest of 34 · top 5 within 0.3s-0.938s (-0.58%)
2:42.725Francisco Barroso · fastest of 35 · top 5 within 0.2s-1.705s (-1.04%)
119.6Wyatt Couch+0.3 mph (+0.3%)
+32.075squal +32.539s
124.6%qual 125.1%
2:27.890Nic Hammann · fastest of 12 · top 5 within 4.0s-0.786s (-0.53%)
2:27.540Scotty B White · fastest of 12 · top 5 within 4.8s-2.358s (-1.57%)
138.4Nic Hammann+0.2 mph (+0.2%)
+16.890squal +18.256s
112.9%qual 114.1%
47 rule changes (GT2: 13, SM: 2, T3: 32)9 cars added · 8 weight · 7 tyres & wheels · 5 suspension & brakes · 2 induction · 2 removed · 1 aero · 5 wording · 8 other · SM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361. · GT2 Panoz Esperante GTS spec simplified to standard GT2 rules unless noted; detailed suspension, brake, aero specs removed. · TA2 shock absorbers rise to $1005, rear calipers to $585, brake pads to $330 per axle; wheels drop to $165. · GT2 Porsche 991.1 GT3 Cup now permits modifications from Grand Am, IMSA Cup, World Challenge rules; factory Lexan windows and ABS allowed. · GT2-ST Corvette C7 L76 minimum weight drops 100 lbs to 3000, restrictor rises to 83 mm FPR. · GT2 Porsche 997.2 GT3 Cup removes permission for Lexan front windows and clarifies ABS allowance status. · SM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. · Ginetta G56 GT4 (V8) added to GT2 with GM LS V8, 6.2L, 72mm restrictor, 3300 lbs. · GT3U class removed from GCR; GT3U cars now compete in STU. · GT2 Audi R8 GT4 removes requirement to carry GT4 rules at events, directs to GT2-ST header note. · GT2 Porsche 911 SC gains 4.0L air-cooled engine option at 2275 or 2350 lbs depending on valve count. · M3 E92 classified in GT2 with 3999cc V8, 35mm restrictor, 3300 lb minimum weight. · T2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously only spherical bearings permitted. · 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 Camaro/Mustang/Camry. · GT2 Mazda BP 1839cc DOHC classified with 2250 lbs minimum weight, 46mm restrictor, EFR6258 or EFR7163 turbo allowed. · T2, T3, T4 now allow under-dash electronics relocation for access after roll cage installation. · T4 Performance clarified: 1-piece alternative rotors permitted only at sizes listed in spec line; alternate brake kits may use matching 1-piece rotors. · T3 and T4 Mazda MX-5 Miata add permitted gearset kit PT#0000-02-6100 to Notes. · T4 MX-5 Miata 19-24 and 16-18, T3 MX-5 16-18 and Global Cup ND1/ND: discontinued DG Motorsports hardtop part #0000-07-5901 removed from permitted list.showhide
T3 Allow T3 Ford Mustang 4.6 to Use the Coyote MT-82 6 speed. #40190other
T3 Porsche 986S Boxster S (2000-2004) Minimum Weight #40196weight
GT2 Panoz Esperante GTS Letter ID Number: #38494 - Additional Info #38584wordingunclearGT2 Panoz Esperante GTS spec simplified to standard GT2 rules unless noted; detailed suspension, brake, aero specs removed.
GT2 Appendix L Update #39923otherotherTA2 shock absorbers rise to $1005, rear calipers to $585, brake pads to $330 per axle; wheels drop to $165.
GT2 GT2 Porsche 997.2 GT3 Cup EDIT #40125otheraddedGT2 Porsche 991.1 GT3 Cup now permits modifications from Grand Am, IMSA Cup, World Challenge rules; factory Lexan windows and ABS allowed.
T3 2019 Mustang 2.3L Ecoboost Request #39935weight -50 lbs
GT2 Corvette C7 (14-19) L76 Specline Errors/Missing Changes #39838weight -100 lbsfaster · weightGT2-ST Corvette C7 L76 minimum weight drops 100 lbs to 3000, restrictor rises to 83 mm FPR.
GT2 GT2 Porsche 997.2 GT3 Cup #39936wordingwordingGT2 Porsche 997.2 GT3 Cup removes permission for Lexan front windows and clarifies ABS allowance status.
SM Part Number Change Request #39914otherunclearSM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c.
GT2 Classification Request - Ginetta G56 GT4 (V8) #39625cars addedaddedGinetta G56 GT4 (V8) added to GT2 with GM LS V8, 6.2L, 72mm restrictor, 3300 lbs.
GT2 Remove GT3U from GCR as it is now in STU #39862cars addedremoved · cars addedGT3U class removed from GCR; GT3U cars now compete in STU.
GT2 Audi R8 GT4 remove spec line notes #39864wordingwordingGT2 Audi R8 GT4 removes requirement to carry GT4 rules at events, directs to GT2-ST header note.
GT2 Allow Larger Air Cooled Engines in Porsche 911 GT2 #39249cars addedaddedGT2 Porsche 911 SC gains 4.0L air-cooled engine option at 2275 or 2350 lbs depending on valve count.
GT2 Classify T1 BMW in GT2 #39408cars addedaddedM3 E92 classified in GT2 with 3999cc V8, 35mm restrictor, 3300 lb minimum weight.
T3 Please change 2011-2014 Mustang V6 Spec Line to 2005-2014 #39558other
T3 Nissan 350Z Weight Request #39598weight -25 lbs
T3 Allow Alt Bushing Material in Toe Links #39607suspension & brakesadded · suspension & brakesT2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously only spherical bearings permitted.
GT2 Additional Body Options to Replace Older Stock Car Bodies #39086cars addedaddedGT2 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 Camaro/Mustang/Camry.
GT2 GT3 Turbo to GT2? #39365cars addedaddedGT2 Mazda BP 1839cc DOHC classified with 2250 lbs minimum weight, 46mm restrictor, EFR6258 or EFR7163 turbo allowed.
GT2 Tech Bulletins for GT2 and GT2-ST #39537cars added -100 lbs
T3 Request to Allow Spec Mustang to Touring 3 in Appendix M Trim #39196weight -50 lbs
T3 Tire Help for Spec E9X in T3 #39222tyres & wheels
T3 Alternate Placement of Fuse Panel and Electronics Request #39370otheraddedT2, T3, T4 now allow under-dash electronics relocation for access after roll cage installation.
T3 Clarify T4 Brake Rotor Allowance #39503wordingwordingT4 Performance clarified: 1-piece alternative rotors permitted only at sizes listed in spec line; alternate brake kits may use matching 1-piece rotors.
T3 T3 Ecoboost Mustang clarification #39236suspension & brakes
T3 Make the S2000 Competitive Again #38470tyres & wheels
T3 ND Gearset Request for T4 #39166otheraddedT3 and T4 Mazda MX-5 Miata add permitted gearset kit PT#0000-02-6100 to Notes.
T3 ND Spec Lines Wrong PT#'s #39170removedremovedT4 MX-5 Miata 19-24 and 16-18, T3 MX-5 16-18 and Global Cup ND1/ND: discontinued DG Motorsports hardtop part #0000-07-5901 removed from permitted list.
2:11.807Brad McAllister · fastest of 16 · top 5 within 3.4s-0.053s (-0.04%)
2:13.447John Atwell · fastest of 13 · top 5 within 3.6s+0.136s (+0.10%)
163.3Charlie Peter-1.0 mph (-0.6%)
2:43.111Bobby Gossett · fastest of 32 · top 5 within 0.3s+2.005s (+1.24%)
2:44.430Kyle Greenhill · fastest of 28 · top 5 within 0.3s+2.944s (+1.82%)
119.3Francisco Barroso-0.6 mph (-0.5%)
+30.983squal +31.304s
123.2%qual 123.7%
2:28.676Nic Hammann · fastest of 19 · top 5 within 1.8s+3.226s (+2.22%)
2:29.898Marshall Mast · fastest of 19 · top 5 within 2.9s+0.707s (+0.47%)
138.2Marshall Mast-13.0 mph (-8.6%)
+16.451squal +16.869s
112.3%qual 112.8%
35 rule changes (GT2: 7, SM: 4, T3: 24)7 cars added · 4 induction · 4 weight · 2 aero · 2 tyres & wheels · 1 engine · 1 removed · 10 wording · 4 other · GT2 Porsche 911, 963, 994 may use 993 3.8 RSR rear deck lid or faithful aftermarket reproductions. · T2, T3, T4 spec table header changed from T2 to ET. · SMX drivers must submit data acquisition files on time or face suspension and $250 fine. · SMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines. · SM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only. · GT2 Pontiac Fiero drivetrain changed to RWD and hood bulge permitted for front engine relocation. · TA2 OEM wing height rule exemption removed; STO permits factory aero but bans it with aftermarket wings. · GT2 STO aftermarket ABS weight penalty reduced from 100 lbs to 50 lbs. · Ford SCCA Club Spec Mustang added to T3 at 3350 lbs; Mazda SCCA Club Spec MX-5 added to T4 at 2500 lbs. · GT2 Panoz Esperante GTS adds 2013-2016 Ford EcoBoost Twin Turbo V-6, 3496 cc, 2600 lbs, twin turbo induction. · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit. · GT2 Sunbeam Tiger gains Holly 650 cfm carburetors PN #80541-1 and PN #80541-2 as alternate options. · T2, T3, T4: nine, nine, and thirty-seven expired spec lines removed effective 2025-01-01. · SMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation. · T2, T3 Mustang spec lines remove redundant driveshaft allowance notes across six model year ranges. · T2, T3, T4 fuel cell installations may omit charcoal canisters, emissions valves, and sensors. · T2, T3, T4 brake specifications clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter. · T2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors. · Porsche Spec Boxster moves to T4, minimum weight 2750 lbs, ineligible for Runoffs until 3 Super Tour events. · T4 BMW 320i Spec Line: Turner Motorsports intercooler #024703TMS02 now allowed. · 2005 Cadillac CTS 3.6L 6-speed manual classified in T3 Spec.showhide
GT2 Rear Deck Lid for Older Air-Cooled Porsche #38506aeroadded · aeroGT2 Porsche 911, 963, 994 may use 993 3.8 RSR rear deck lid or faithful aftermarket reproductions.
T3 Incorrect Touring Heading #38451wordingwordingT2, T3, T4 spec table header changed from T2 to ET.
SM SMX Data Submission - Penalties #38248otheraddedSMX drivers must submit data acquisition files on time or face suspension and $250 fine.
SM Committee) SMX Penaly Clarification updated language #38337wordingwordingSMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines.
SM Clarify Tire Marking Regs #38005wordingwordingSM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only.
T3 Request to Classify Club Spec in Appropriate Touring Classes #37523cars addedaddedFord SCCA Club Spec Mustang added to T3 at 3350 lbs; Mazda SCCA Club Spec MX-5 added to T4 at 2500 lbs.
SM E&O SMX Regs 9.1.7.1.D.5.u-.w #37070wordingwordingSMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation.
T3 Redundant Verbiage Regarding Mustang Spec Lines for Driveshaft #36484wordingwordingT2, T3 Mustang spec lines remove redundant driveshaft allowance notes across six model year ranges.
T3 Fuel Emissions Components #37076otheraddedT2, T3, T4 fuel cell installations may omit charcoal canisters, emissions valves, and sensors.
T3 fix brake wording #37129wordingwordingT2, T3, T4 brake specifications clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter.
T3 Evaporative emissions systems #37130otheraddedT2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors.
T3 Allow Spec MX5 upgrade kit for 2009-11 RX8 S2 Transmision #37140other
T3 Move Spec Boxster to T4 #37158cars addedaddedPorsche Spec Boxster moves to T4, minimum weight 2750 lbs, ineligible for Runoffs until 3 Super Tour events.
T3 BMW 320i Spec Line #37204engineadded · engineT4 BMW 320i Spec Line: Turner Motorsports intercooler #024703TMS02 now allowed.
T3 Classification for a 2005 Cadillac CTS 3.6 liter 6 speed manual #37224cars addedadded2005 Cadillac CTS 3.6L 6-speed manual classified in T3 Spec.
2:11.860Charlie Peter · fastest of 23 · top 5 within 1.1s-0.438s (-0.33%)
2:13.311John Atwell · fastest of 23 · top 5 within 0.9s-0.968s (-0.72%)
164.3Jonathan Start+2.1 mph (+1.3%)
2:41.106Ethan Goulart · fastest of 49 · top 5 within 0.5s-1.103s (-0.68%)
2:41.486Brett Kowalski · fastest of 43 · top 5 within 0.3s-2.262s (-1.38%)
119.9Alex Bertagnoli-1.4 mph (-1.2%)
+28.175squal +29.246s
121.1%qual 122.2%
2:25.450Scotty B White · fastest of 22 · top 5 within 4.5s-4.307s (-2.88%)
2:29.191Marshall Mast · fastest of 21 · top 5 within 1.8s-2.497s (-1.65%)
151.2Scotty B White+13.1 mph (+9.5%)
+15.880squal +13.590s
111.9%qual 110.3%
58 rule changes (GT2: 13, SM: 4, T3: 41)11 cars added · 10 weight · 7 induction · 6 engine · 5 suspension & brakes · 2 tyres & wheels · 1 aero · 5 wording · 11 other · SMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification. · SM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01. · SMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only. · SM and SMX now allow an alternate shifter bushing at the bottom of the shift lever. · GT2-ST: aftermarket replacement differential housings permitted if exact equivalent. · GT4 cars now permitted in GT2-ST with factory power stick or Pro Series restrictor, 100-pound weight penalty for slicks. · T2 Mustang GT 5.0L 15-17 and 2018- now permit Track/Performance Package parts; T3 V6 15-17 clarified to allow Track/Performance package. · T2-T4 Ford Mustangs: remove 25 lb penalty for non-OEM driveshaft, clarify alternate driveshaft allowance. · Audi S4 (2000–2002) classified in T3 with 2671cc, 3400 lbs minimum weight, 38mm restrictor, allowing 800lb springs and intercooler. · GT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR. · GT2-ST Spec Corvette (14-19) LS2 restrictor increases from 78mm to 80mm flat plate. · T3 and T4 Mazda RX-8 may remove or disable factory oil injection system. · T2, T3, T4 driveshafts may use carbon fiber, aluminum, or steel; two-piece replaced with one-piece; non-OEM adds 25 lbs. · Chevrolet Corvette C8 (2020–) classified in GT2-ST: 6162 cc, 3300 lbs minimum, 71 mm restrictor, flat plate. · Mitjet ST 2015 added to GT2, must run per VTS specs with FIA form CdM008. · T2, T3, T4 Spec Lines remove wheelbase requirement, add Required Restrictor specification. · T2 and T3 Nissan 370Z front brake rotors increase to 355×32 mm, rears to 350×20 mm. · GT1-GTX rear blade spoiler: angle 50–75°, max 59.0 wide by 5.0 high inches; total area limit removed. · GT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment. · GT2 Chevrolet Corvette 7011 OEM 7-liter minimum weight reduces to 3125 lbs, down 150 lbs. · GT2 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E. · T2, T3, T4 battery replacement no longer allows alternate manufacturer batteries within 10% OEM weight. · T4 now allows C-Spec touring cars to compete, in addition to existing B-Spec eligibility. · T2, T3, T4 spec lines expire 12/31/24; submit to appeal or cars are removed from class. · GT2 Dodge Viper Gen 3 hybrid kit restrictor reduced from 50mm to 45mm flat plates in 8300 class. · T3 Nissan 370Z now includes model years 2009–2022 with Nismo editions. · GTL spec lines moved contiguous with GT2 and GT3; GTA category and specs renumbered behind GTL; P2 engine tables reorganised with restrictor and weight specifications clarified. · GT2-ST Dodge Viper including Comp Coupe, ACR/ACR-X adds VRL front fascia, 100 lbs weight reduction.showhide
SM SMX Camera Rule Correction #36496wordingwordingSMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification.
SM Committee) AIM ECU Protocol #36556engineadded · engineSM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01.
SM Committee) OE versus OEM Definitons #36608wordingwordingSMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only.
SM Committee) Shifter Bushing #36611otheraddedSM and SMX now allow an alternate shifter bushing at the bottom of the shift lever.
GT2 GT4 cars may run in GT2-ST #36235cars addedaddedGT4 cars now permitted in GT2-ST with factory power stick or Pro Series restrictor, 100-pound weight penalty for slicks.
T3 Mustang T2/T3 #35877cars addedaddedT2 Mustang GT 5.0L 15-17 and 2018- now permit Track/Performance Package parts; T3 V6 15-17 clarified to allow Track/Performance package.
T3 T2-T4 Driveshaft Mistake...? #36050weightfaster · weightT2-T4 Ford Mustangs: remove 25 lb penalty for non-OEM driveshaft, clarify alternate driveshaft allowance.
T3 E&O: #35174 (Derek Chan) 350Z Parity Request #36116induction
T3 B8/8.5 Audi S4 T3 and T2 #36195cars addedaddedAudi S4 (2000–2002) classified in T3 with 2671cc, 3400 lbs minimum weight, 38mm restrictor, allowing 800lb springs and intercooler.
GT2 Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslower · weightGT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR.
GT2 Request to Eliminate the FPR from the Corvette (-2013) with LS2 #35878enginefaster · engineGT2-ST Spec Corvette (14-19) LS2 restrictor increases from 78mm to 80mm flat plate.
T3 Allow T4 and T3 RX8 to Disable/Remove Factory Oil Inj. #35761engineadded · engineT3 and T4 Mazda RX-8 may remove or disable factory oil injection system.
T3 Driveshafts #35916weightslower · weightT2, T3, T4 driveshafts may use carbon fiber, aluminum, or steel; two-piece replaced with one-piece; non-OEM adds 25 lbs.
GT2 Classify Corvette C8 (2020- ) into GT2/ST #33759cars addedaddedChevrolet Corvette C8 (2020–) classified in GT2-ST: 6162 cc, 3300 lbs minimum, 71 mm restrictor, flat plate.
GT2 Requesting classification for a 2015 Mitjet ST in GT2 #35408cars addedaddedMitjet ST 2015 added to GT2, must run per VTS specs with FIA form CdM008.
T3 370Z Brake Rotor Size Correction #35487suspension & brakessuspension & brakesT2 and T3 Nissan 370Z front brake rotors increase to 355×32 mm, rears to 350×20 mm.
GT2 Rear Blade Spoiler Clarification #35261aeroaeroGT1-GTX rear blade spoiler: angle 50–75°, max 59.0 wide by 5.0 high inches; total area limit removed.
GT2 GT Direct Injection allowance and rules #35437engineadded · engineGT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment.
GT2 REDUCE C6 CORVETTE WEIGHT WITH OEM 7 LITER ENGINE REDUCE BY 150LB #35385weight -150 lbsfaster · weightGT2 Chevrolet Corvette 7011 OEM 7-liter minimum weight reduces to 3125 lbs, down 150 lbs.
GT2 GT2/3 remove Direction Injection not allowed in Spec line notes #35439engineadded · engineGT2 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E.
T3 15-18 Golf R Alignment with Existing GTI and R Speclines #35235tyres & wheels
T3 More Car Lightening Stuff #35319wordingremovedT2, T3, T4 battery replacement no longer allows alternate manufacturer batteries within 10% OEM weight.
T3 Open Strut Tower Brace Options for Ford Mustang V6 (11-14) #35322suspension & brakes
T3 Inclusion of B-C spec cars in T4 #35374cars addedaddedT4 now allows C-Spec touring cars to compete, in addition to existing B-Spec eligibility.
T3 T2-T4 Set expiration dates on spec lines #35378wordingremovedT2, T3, T4 spec lines expire 12/31/24; submit to appeal or cars are removed from class.
GT2 Dodge Viper Gen 3 hybrid Kit Update Request #35200engineslower · engineGT2 Dodge Viper Gen 3 hybrid kit restrictor reduced from 50mm to 45mm flat plates in 8300 class.
T3 Requested Update of Model Years of 370Z #35231cars addedaddedT3 Nissan 370Z now includes model years 2009–2022 with Nismo editions.
T3 Update Request for 2010 Mustang GT 4.6 #35234other
T3 SE46 Continued Parity/ Cold Air Intake request #35267induction -50 lbs
T3 Please help the Subaru STIs. #35278weight +100 lbs
GT2 Errors in GTCS Headings and Use of the Terms Category and ClassChange existing GTL and GTA Rules #34453wordingwordingGTL spec lines moved contiguous with GT2 and GT3; GTA category and specs renumbered behind GTL; P2 engine tables reorganised with restrictor and weight specifications clarified.
T3 Porsche Cayman Transmissions and Ratios #34891weight
T3 2006-10 Volkswagen GTI - Weight Reduction request and KO4 Turbo #34414weight
T3 Adding Model Years to T3 Golf R Spec Line #34612other
T3 Rear Camber Arms for T3 VW Golf R #34613suspension & brakes
T3 Classing Spec E90 Cars in SCCA #34791cars added
T3 TIR location requirement in VW Golf Spec lines #35048induction
GT2 Late E & O #34966weightfaster · weightGT2-ST Dodge Viper including Comp Coupe, ACR/ACR-X adds VRL front fascia, 100 lbs weight reduction.
1:52.004Barry Boes · fastest of 15 · top 5 within 1.6s+0.918s (+0.83%)
1:52.865Jared Odrick · fastest of 15 · top 5 within 1.0s-0.183s (-0.16%)
164.0Tom Patton-0.2 mph (-0.1%)
2:14.986Danny Steyn · fastest of 52 · top 5 within 0.1s+0.322s (+0.24%)
2:16.229Julian DaCosta · fastest of 46 · top 5 within 0.3s-2.878s (-2.07%)
120.3Jim Drago+1.1 mph (+0.9%)
+23.364squal +22.982s
120.7%qual 120.5%
2:04.520Steve Ott · fastest of 18 · top 5 within 1.9s+0.297s (+0.24%)
2:05.854Chris Hart · fastest of 18 · top 5 within 1.8s-21.772s (-14.75%)
139.1Jason Ott-1.1 mph (-0.8%)
+12.989squal +12.516s
111.5%qual 111.2%
48 rule changes (GT2: 19, SM: 1, T3: 28)10 weight · 9 cars added · 7 engine · 4 tyres & wheels · 3 induction · 2 aero · 2 suspension & brakes · 1 removed · 3 wording · 7 other · GT2 Mazda 20B rotary minimum weight reduced to 2280 lbs, with 100-lb penalty for Grand Am transaxle and independent rear suspension. · Mazda RX-8 T3 and T4 transmission and final drive pairing requirement removed; T4 gains Mazdaspeed radiator, spring kit, restrictor, spoiler, air dam. · T3 BMW 320i 14–15 gains aftermarket intercooler; T4 BMW 320i 14–15 loses it. · T3 and T2 Pontiac Solstice GXP 07-09 minimum ride height set to 3 inches. · GT2 BMW E46 M3, E36, Z3, 5000cc V8: 3.4L at 2575 lbs, 4.0L at 2900 lbs, 4.5L at 2950 lbs, 5.0L at 3000 lbs; S54 97mm stroke permitted at 2800 lbs. · GT2 Corvette C7 restrictor increases from 73mm to 77mm flat plate. · GT2 adds 2009-2012 Porsche Cayman S, 3.4L, RWD, no PDK transmission. · Fields Cardinal V8 added to GT1 with Ford V8 engine, 4.9L, 2100 lbs, fuel injection. · GT2 Ginetta G56 GTA may use Factory installed ProMap ECU Map. · GT2 Mazda 13B Street Port turbo changes from EFR 76/70 to BW7670 or Garrett G30-660 with 46mm TIR at 2280 lbs. · T2 and T3 Mustang 11-14 may remove upper grille fog lights, replace with mesh or screen. · GT2 Porsche SOHC 2478/2681/2992 turbos: EFR 76/70 compressor 42mm to 44mm, SIR to TIR designation. · GT2-ST Chevrolet Corvette 14-19 restrictor increases from 70 to 73 mm. · GT2 and GTL add Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines as permitted options. · GT2 Mazda 13B turbocharger part number changed from EFR 70/76 to 76/70, compressor 42mm to 46mm. · GT2-ST BMW E36/46 spec line adds MA Shaw carbon/composite door and body kit options to notes. · GT3 normally aspirated cars may now use chokes instead of SIRs, same size as listed SIR, one per carburetor barrel. · GT3 2.0L 4-valve non-turbo engines may run unrestricted at 2060 lbs minimum weight. · GT2 Porsche 991.1 TBR 70–72mm, 991.2 weight 3100–3000lbs TBR 65–67mm, all 991/997 models ABS now free; GT2-ST Corvette and others flat plate 75–78mm, 74–77mm, 71–74mm, 68–71mm, 65–68mm per engine; Viper weight 3275–3125lbs all displacement… · SM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. · T5 touring class added; T2-T5 cars may race one class up; T5 maximum tyre width 225 with minimum aspect ratio 45. · T2-T5 Touring front and rear suspension maximum negative camber clarified to 3.5 degrees. · GT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870. · GT2 Ginetta G56 GTA may now use optional 18" x 9" and 18" x 10" wheels. · GT2/ST BMW E36/E46 Z3 5000cc V8 now permits MAShaw body kit: wide body, M3 front bumper with splitter, fenders, rockers, flairs, rear bumper. · GT2 Chevrolet Corvette L76 5967 restrictor increases from 73 mm to 74 mm.showhide
GT2 GT2 Mazda 20B 3 rotor ENO #34765weight -220 lbsfaster · weightGT2 Mazda 20B rotary minimum weight reduced to 2280 lbs, with 100-lb penalty for Grand Am transaxle and independent rear suspension.
T3 2012-2013 Golf R - added to T3 #34413cars added
T3 Rules Clarification for Mazda RX8 Spec Line #34395wordingwordingMazda RX-8 T3 and T4 transmission and final drive pairing requirement removed; T4 gains Mazdaspeed radiator, spring kit, restrictor, spoiler, air dam.
T3 rule book corrections #34437otheraddedT3 BMW 320i 14–15 gains aftermarket intercooler; T4 BMW 320i 14–15 loses it.
T3 Allowing 255 Tire Width for Nissan 350z #34471tyres & wheels
T3 Ride Height Correction for the T3 Solstice. #34615suspension & brakessuspension & brakesT3 and T2 Pontiac Solstice GXP 07-09 minimum ride height set to 3 inches.
GT2 appendix letter #33635 #34206cars addedaddedGT2 BMW E46 M3, E36, Z3, 5000cc V8: 3.4L at 2575 lbs, 4.0L at 2900 lbs, 4.5L at 2950 lbs, 5.0L at 3000 lbs; S54 97mm stroke permitted at 2800 lbs.
GT2 Remove Weight and Restrictor Penalty for Corvette C7 Body #34342enginefaster · engineGT2 Corvette C7 restrictor increases from 73mm to 77mm flat plate.
T3 2016+ Camaro 1LE - Max Wheel Diameter #34003tyres & wheels
GT2 GT2 Mazda 13B Turbo #33729engineengineGT2 Mazda 13B Street Port turbo changes from EFR 76/70 to BW7670 or Garrett G30-660 with 46mm TIR at 2280 lbs.
T3 Request to classify 2014 Base Cayman #33159cars added
T3 Mustang OEM Grill Request #33333aeroadded · aeroT2 and T3 Mustang 11-14 may remove upper grille fog lights, replace with mesh or screen.
T3 Adjustable Rear Camber Arms for VW (All Generations) #33572suspension & brakes
GT2 Request Permission to Use a Substitute Turbo #33337engineengineGT2 Porsche SOHC 2478/2681/2992 turbos: EFR 76/70 compressor 42mm to 44mm, SIR to TIR designation.
GT2 Request to Reduce Restriction on C7 GT2 Corvette #33342enginefaster · engineGT2-ST Chevrolet Corvette 14-19 restrictor increases from 70 to 73 mm.
GT2 Toyota 4A-F and 4A-FE 1.6L DOHC 16V Engine Request #33415cars addedaddedGT2 and GTL add Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines as permitted options.
GT2 GT2 Mazda 13b turbocharger part # update #33437enginefaster · engineGT2 Mazda 13B turbocharger part number changed from EFR 70/76 to 76/70, compressor 42mm to 46mm.
GT2 GT2-ST BMW E36/46 spec line remove #33610otheraddedGT2-ST BMW E36/46 spec line adds MA Shaw carbon/composite door and body kit options to notes.
GT2 GT3 Choke option effective 1-01-2023 #33669inductionadded · inductionGT3 normally aspirated cars may now use chokes instead of SIRs, same size as listed SIR, one per carburetor barrel.
GT2 GT3 2.0L choke/weight option #33670otheraddedGT3 2.0L 4-valve non-turbo engines may run unrestricted at 2060 lbs minimum weight.
GT2 BOP adjustment for GT2 & GT2-ST #33681inductionfaster · inductionGT2 Porsche 991.1 TBR 70–72mm, 991.2 weight 3100–3000lbs TBR 65–67mm, all 991/997 models ABS now free; GT2-ST Corvette and others flat plate 75–78mm, 74–77mm, 71–74mm, 68–71mm, 65–68mm per engine; Viper weight 3275–3125lbs all displacement…
SM BOP for NB1 and NB2 #32309weightslower · weightSM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore.
T3 350z SPC Upper Control Arm Safety Concerns #33020weight
T3 Touring (T2-T5) Category #33617cars addedaddedT5 touring class added; T2-T5 cars may race one class up; T5 maximum tyre width 225 with minimum aspect ratio 45.
T3 ENO 9.1.9.2.D.1.e.1.a. #33651wordingwordingT2-T5 Touring front and rear suspension maximum negative camber clarified to 3.5 degrees.
GT2 GT2 (TA2)/GTA Part Number Update #33315wordingwordingGT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870.
GT2 Ginetta G56 GTA - Optional Wheels #33357tyres & wheelsadded · tyres & wheelsGT2 Ginetta G56 GTA may now use 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 #32447aeroadded · aeroGT2/ST BMW E36/E46 Z3 5000cc V8 now permits MAShaw body kit: wide body, M3 front bumper with splitter, fenders, rockers, flairs, rear bumper.
GT2 Request for C5/C6 Corvette Restrictor Size Review #32982enginefaster · engineGT2 Chevrolet Corvette L76 5967 restrictor increases from 73 mm to 74 mm.
T3 Another 2022 BRZ/86 T3 request #32945weight +225 lbs
1:51.086Andrew Aquilante · fastest of 23 · top 5 within 1.1s+0.904s (+0.82%)
1:53.048Daniel Bender · fastest of 17 · top 5 within 3.1s+0.573s (+0.51%)
164.2Scotty B White+1.4 mph (+0.9%)
2:14.664Danny Steyn · fastest of 60 · top 5 within 0.2s+0.112s (+0.08%)
2:19.107Travis Wiley · fastest of 58 · top 5 within 0.9s+2.648s (+1.94%)
119.2Jonathan Neudorf-0.6 mph (-0.5%)
+26.059squal +23.578s
123.1%qual 121.2%
2:04.223Jason Ott · fastest of 20 · top 5 within 2.1s-0.695s (-0.56%)
2:27.626Marshall Mast · fastest of 19 · top 5 within 4.1s+22.272s (+17.77%)
140.2Jason Ott+2.0 mph (+1.4%)
+34.578squal +13.137s
130.6%qual 111.8%
46 rule changes (GT2: 14, SM: 1, T3: 31)11 cars added · 10 weight · 5 engine · 2 aero · 2 induction · 1 suspension & brakes · 1 tyres & wheels · 7 wording · 7 other · GT1, GT2, GT3, GTL, GTX tail lights may now be original style or custom panel graphic with functioning red LED brake lamps. · Ginetta GTA G56 added to GT2 as spec car, 2600 lbs, 3.7L Ford V6 sealed, 6-speed Quaife sequential. · GT2 adds approved carbon roof suppliers and part numbers for BMW E36 and E46 models to Notes. · GT2 BMW E46 M3, E36, Z3, and 5000cc V8 may use 95mm S54 crankshaft at +150 lbs. · Audi R8 GT4 added to GT2 at 5.2L, 3000 lbs minimum weight, factory restrictor. · GT2 shock absorber attachment points clarified as movable; wording correction only. · GT2 Porsche 104.0 x 88.0 SOHC minimum weight increases to 2090 lbs; EFR 76/70 turbo allowances added for three Porsche engines at specific weights. · T2-T4 Touring cars with alternative springs now permitted to use performance top hats with spherical bearings on shocks and struts. · SM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation. · T2-T4 touring cars model year 2018+ may use aftermarket ECU with 75 lb weight penalty via spec line adjustment. · Ginetta G40 added to GT2 with Mazda MZR/L5-VE engine, 2488cc or 2399cc, 1950 lbs base weight. · Toyota Supra GT4 added to GT2-ST with 3000cc displacement, 3000 lb minimum weight, factory restrictor. · GT2 Porsche 944/924 may use ERC 76/70 Turbo instead of Jayco super 50. · T2-T4 grill opening removal for cooling permitted without 16 square inch limit; mesh shape must match factory. · GT2-ST Porsche Cayman 05-15 throttle body restrictor increased from 70mm to 75mm. · GT2 Porsche Cayman 05-15 4.0L and 4.2L swap flat plate restrictor for throttle body restrictor at 2700 lbs. · T2, T3, T4 clarify grill opening removal limited to 16 square inches for radiator cooling; mesh shape must be retained. · T2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted. · T2, T3, T4: clarified that 'permitted' or 'allowed' parts in spec lines are alternatives to category rule allowances, not replacements. · T4 adds 2014 VW Jetta 1.8T TSI to Spec Lines. · GT2 Mazda 13B street port gains EFR 70/76 turbocharger with 42mm inlet restrictor at 2280 lbs minimum. · GT3 Volkswagen Fun Cup Beetle EVO3 classified, sealed SOHC 1984cc engine, 2060 lbs minimum weight.showhide
GT2 Tail lights on all GT category race cars. #32799wordingwordingGT1, GT2, GT3, GTL, GTX tail lights may now be original style or custom panel graphic with functioning red LED brake lamps.
GT2 Addendum to letter #32514 Ginetta GTA G56 #33076cars addedaddedGinetta 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 #32682cars addedaddedGT2 adds approved carbon roof suppliers and part numbers for BMW E36 and E46 models to Notes.
GT2 Request to Allow the 95mm S54 BMW Crankshaft in GT2-ST #32698engineadded · engineGT2 BMW E46 M3, E36, Z3, and 5000cc V8 may use 95mm S54 crankshaft at +150 lbs.
GT2 Request to classify Audi R8 FIA GT4 to GT2 #32805cars addedaddedAudi R8 GT4 added to GT2 at 5.2L, 3000 lbs minimum weight, factory restrictor.
T3 Request Alternate Front & Rear Strut/Shock Top Hats #32452suspension & brakesadded · suspension & brakesT2-T4 Touring cars with alternative springs now permitted to use performance top hats with spherical bearings on shocks and struts.
T3 2022 Subaru BRZ and Toyota 86 twins #32483weight
SM Update GCR Section 9.1.7.3.A.1. #32217wordingwordingSM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation.
T3 Request to Allow the Use of Aftermarket ECU's in Touring #31067engineadded · engineT2-T4 touring cars model year 2018+ may use aftermarket ECU with 75 lb weight penalty via spec line adjustment.
GT2 Request to Classify Ginetta G40 in GT2 #31597cars addedaddedGinetta G40 added to GT2 with Mazda MZR/L5-VE engine, 2488cc or 2399cc, 1950 lbs base weight.
GT2 2021 Supra GR GT4 #31737cars addedaddedToyota Supra GT4 added to GT2-ST with 3000cc displacement, 3000 lb minimum weight, factory restrictor.
GT2 Proposed Technical Bulletin #31900otherunclearGT2 Porsche 944/924 may use ERC 76/70 Turbo instead of Jayco super 50.
T3 Touring 3 BOP adjustments for 2022 #31481weight +75 lbs
T3 BMW 330i Minimum Comp Weight #31606weight -60 lbs
T3 Reply to letter #31486/29879 T2-T4 Grill openings #31935aerofaster · aeroT2-T4 grill opening removal for cooling permitted without 16 square inch limit; mesh shape must match factory.
T3 Remove StopTech 4 piston BBK, allow any 4 Piston Kit - VW GTI #33082weight
GT2 GT2/ST Porsche Cayman #31451 correct TBR size error #31991enginefaster · engineGT2-ST Porsche Cayman 05-15 throttle body restrictor increased from 70mm to 75mm.
GT2 Restrictor Clarification for 2015 Cayman #31451otherunclearGT2 Porsche Cayman 05-15 4.0L and 4.2L swap flat plate restrictor for throttle body restrictor at 2700 lbs.
T3 Request FRS/BRZ/86 T3 Weight Reduction #30818weight -75 lbs
T3 Request to Classify 2022 Toyota 86 / Subaru in T3 & T4 #30931cars added
T3 Reply to letter 29879 T2-T4 Grill Openings #31486wordingwordingT2, T3, T4 clarify grill opening removal limited to 16 square inches for radiator cooling; mesh shape must be retained.
T3 Please Adjust Years Allowed for BMW 335i to 07-10, not 08-13 #31530other
T3 Please Adjust Years Allowed for BMW 135i to 08-10, not 08-13 #31531other
T3 Request to clarify radiator hoses #31682otheraddedT2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted.
T3 Clarify Permitted/Allowed #31743wordingwordingT2, T3, T4: clarified that 'permitted' or 'allowed' parts in spec lines are alternatives to category rule allowances, not replacements.
T3 Request to correct model years BMW Z4 M Coupe #31371wording
GT2 Turbo Request for 13B Engine #30656engineadded · engineGT2 Mazda 13B street port gains EFR 70/76 turbocharger with 42mm inlet restrictor at 2280 lbs minimum.
GT2 Request car classification #31032cars addedaddedGT3 Volkswagen Fun Cup Beetle EVO3 classified, sealed SOHC 1984cc engine, 2060 lbs minimum weight.
1:39.665Andrew Aquilante · fastest of 22 · top 5 within 1.8s-0.254s (-0.25%)
2:03.513Tim Kezman · fastest of 18 · top 5 within 9.6s+22.537s (+22.32%)
163.7Jonathan Start
1:57.695Brian Henderson · fastest of 90 · top 5 within 0.5s-0.611s (-0.52%)
1:58.837Brian Henderson · fastest of 88 · top 5 within 0.3s-0.263s (-0.22%)
119.8Kyle Greenhill
-4.676squal +18.030s
96.2%qual 118.1%
1:51.591Marshall Mast · fastest of 23 · top 5 within 0.9s-0.623s (-0.56%)
1:52.701Breton Williams · fastest of 22 · top 5 within 0.7s-0.585s (-0.52%)
136.4Jason Ott
-10.812squal +11.926s
91.2%qual 112.0%
36 rule changes (GT2: 16, SM: 1, T3: 19)10 cars added · 9 weight · 2 engine · 2 tyres & wheels · 1 aero · 1 induction · 6 wording · 5 other · GT2 Dodge Viper ACR/ACR-X8300 front fascia loses 100 lbs, to 3175 VRL. · GT2 adds 04-06 World Challenge Pontiac GTO, 6062 cc, 3000 lbs minimum, World Challenge rules. · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two locations and 6010 to 6014X in TA2 Appendix. · Grullon GT 2.0L Acura K20 moved from GTX to GT2-ST class at 2350 lbs unrestricted. · GT2-ST Porsche Cayman restrictor increases from 65mm to 75mm flat plate at 2700 lbs. · GT2 Dodge Viper VRL Spec minimum weight reduced 100 lbs to 3275. · TA2 cars may run prior generation rules or current Trans Am rules at 2930 lbs minimum weight with free tire make and size. · T3 Honda Civic Type-R 2020+ allowed brake rotor #45251-TGH-A01 with 25 lb penalty. · GT2 Sunbeam SBF engine firing order 1,3,7,2,6,5,4,8 now available for Boss 302 variants. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. · T2-T4 clutch discs and pressure plates must be at least 95% of factory OEM weight, bolted to unmodified stock flywheel. · GT2-ST Corvette (-2019) LS2 and L76 5967 gain 100 lbs minimum weight to 3100; 6162 and 7011 variants gain 50–100 lbs; L76 restrictor opens 70 to 73 mm. · GT2 rear engine opening position requirement removed. · GT2 Ford Mustang/Thunderbird Boss 302 firing order changes from unrestricted to optional later SBF 302 order 1,3,7,2,6,5,4,8. · GT2 allows ABS braking systems if shown on the individual Spec Line. · GT2 Corvette C6 and C7 spec lines split for clarification; C7 LS2, L76, LS3, LT1, LS7 weights raised 100–150 lbs effective 3/1/2021. · Toyota Supra 2020- added to T2 with 2998 cc engine, 3450 lbs minimum weight, 19×10 wheels, 295 tyres. · T2 Ford Mustang GT 5.0L 15-17 gear ratios changed to 3.66, 2.43, 1.69, 1.32, 1.00, 0.65 or 4.17, 2.34, 1.52, 1.14, 0.87, 0.69. · GT2 Ford Mustang/Thunderbird Boss 302 firing order becomes unrestricted. · GT2 BMW E46 M3 and E36, Z3, and 5000cc V8 minimum weight reduced to 2500 lbs. · T2 BMW M2 CS Cup 2020+ classified at 2979 cc, 3625 lbs, 295 tires, 10.5×18 wheels, 380/390 mm brakes. · T2 and T3 Nissan 350Z and 370Z permit 44011-RC350 rear caliper kit and SZ350 rotors; T2 350Z also permits Stillen 400338. · T4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, plus 25 lb penalty. · T3 Scion FR-S/Toyota 86 and Subaru BRZ capped to 2021 model year; T4 models capped to 2021. · GT2 Chrysler/Dodge/Plymouth DOHC 2429cc engine classified, 1950 lbs minimum weight. · T3 Alfa Romeo 4C Launch Edition variant now allowed.showhide
GT2 Correct letter 30565 GT2/ST #31088weightfaster · weightGT2 Dodge Viper ACR/ACR-X8300 front fascia loses 100 lbs, to 3175 VRL.
GT2 Request the 04-06 Pontiac GTO WC Car Be Added to the GT2/ST Chart #30339cars addedaddedGT2 adds 04-06 World Challenge Pontiac GTO, 6062 cc, 3000 lbs minimum, World Challenge rules.
GT2 Request to Update GTA Obsolete Part Numbers #30615wordingwordingGTA part numbers updated: 0-80541-1 to 0-80541-2 in two locations and 6010 to 6014X in TA2 Appendix.
GT2 GTX class correction to GT2/ST #30973cars addedaddedGrullon GT 2.0L Acura K20 moved from GTX to GT2-ST class at 2350 lbs unrestricted.
GT2 Porsche Cayman Engine Modification and Engine Request #30472enginefaster · engineGT2-ST Porsche Cayman restrictor increases from 65mm to 75mm flat plate at 2700 lbs.
GT2 Request weight clarification Viper CC #30565weightfaster · weightGT2 Dodge Viper VRL Spec minimum weight reduced 100 lbs to 3275.
GT2 Variance, 2021 TA2 Rules vs GCR Appendix L #30641cars addedaddedTA2 cars may run prior generation rules or current Trans Am rules at 2930 lbs minimum weight with free tire make and size.
T3 Follow-up to letter 29797-Porsche Spec Boxster in T3 Adjustment #30144weight -50 lbs
T3 07-09 and 10-13 Mazdaspeed 3 Fuel Pump #30154other
GT2 GT2 tiger firing order #30421wordingwordingGT2 Sunbeam SBF engine firing order 1,3,7,2,6,5,4,8 now available for Boss 302 variants.
SM Updates - Obsolete Parts & BOP Parts #30438wordingaddedSM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture.
T3 Request consistency review in GCR #30263wordingwordingT2-T4 clutch discs and pressure plates must be at least 95% of factory OEM weight, bolted to unmodified stock flywheel.
T3 Request to classify 2006-2008 Cayman #30315cars added
GT2 GT2-ST CORVETTE CHANGES #30029weight +100 lbsslower · weightGT2-ST Corvette (-2019) LS2 and L76 5967 gain 100 lbs minimum weight to 3100; 6162 and 7011 variants gain 50–100 lbs; L76 restrictor opens 70 to 73 mm.
GT2 29742 Change new wording to read as: #30329wordingwordingGT2 Ford Mustang/Thunderbird Boss 302 firing order changes from unrestricted to optional later SBF 302 order 1,3,7,2,6,5,4,8.
GT2 Request change to engine firing order rule #29742engineadded · engineGT2 Ford Mustang/Thunderbird Boss 302 firing order becomes unrestricted.
GT2 Request E-46 BMW M3 balance of performance #29833weight -100 lbsfaster · weightGT2 BMW E46 M3 and E36, Z3, and 5000cc V8 minimum weight reduced to 2500 lbs.
T3 Request to Classify BMW M2 CS #29523cars addedaddedT2 BMW M2 CS Cup 2020+ classified at 2979 cc, 3625 lbs, 295 tires, 10.5×18 wheels, 380/390 mm brakes.
T3 Allow the SpecMX-5 Update Kit Into Touring 4 for the MX-5 #29681other
T3 350Z Rear Caliper Replacement #29710cars addedaddedT2 and T3 Nissan 350Z and 370Z permit 44011-RC350 rear caliper kit and SZ350 rotors; T2 350Z also permits Stillen 400338.
T3 Request Mustang 8.8†rear axle replacement #29860cars addedaddedT4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, plus 25 lb penalty.
T3 Cap year range on all 86s #29908wordingwordingT3 Scion FR-S/Toyota 86 and Subaru BRZ capped to 2021 model year; T4 models capped to 2021.
GT2 Request for Bigger Engine in Plymouth Breeze #29380cars addedaddedGT2 Chrysler/Dodge/Plymouth DOHC 2429cc engine classified, 1950 lbs minimum weight.
T3 Alfa Romeo 4C Launch Edition #29531cars addedaddedT3 Alfa Romeo 4C Launch Edition variant now allowed.
2:12.298Andrew Aquilante · fastest of 20 · top 5 within 2.9s
2:14.279Andrew Aquilante · fastest of 19 · top 5 within 2.4s
162.2Scotty B White
2:42.209Kyle Greenhill · fastest of 77 · top 5 within 0.5s
2:43.748Preston Pardus · fastest of 75 · top 5 within 1.0s
121.3Kyle Greenhill
+29.469squal +29.911s
121.9%qual 122.6%
2:29.757Marshall Mast · fastest of 29 · top 5 within 2.1s
2:31.688Marshall Mast · fastest of 20 · top 5 within 1.8s
138.1Jason Ott
+17.409squal +17.459s
113.0%qual 113.2%
54 rule changes (GT2: 26, SM: 2, T3: 26)16 cars added · 11 weight · 6 engine · 3 tyres & wheels · 2 induction · 2 suspension & brakes · 1 aero · 10 wording · 3 other · GT2 stock car bodies removal rescinded; 1997-current year commercially available stock car bodywork allowed. · GT2 Appendix L section 4.8.4.2.10.3.6 renumbered, eliminating subsections .17–.19. · GT2 TA2 wing width maximum clarified to 65 -5/16 inches, including end plates. · SM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A. · GT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line. · Chevrolet Corvette (-2019) GT2-ST permitted LS1/LS6 alternate intake manifold, DORMAN part # 615-900. · GT2 997.2 GT3 Cup minimum weight reduced from 3000 to 2900 lbs. · GT2 BMW E46 M3, E36, Z3, and 5000cc V8 gain Trans Am SGT option: 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, ahead of windscreen. · SM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure. · TA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications. · STO rear wing rules clarify that wicker is called Gurney flap in two places; no performance change. · GT Gurney flap wording clarified: wickerbill and tab terminology replaced with Gurney flap throughout sections 9.1.2.F.7.b. · Request to add vehicle to T2, T3, T4 roster; refer to letter #27663 in June 2020 Fastrack for decision. · GT2 Dodge Viper 8.4 OEM minimum weight reduced to 3275 lbs. · GT2 Chevrolet Corvette -2019 OEM minimum weight reduced to 3275 lbs. · 2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine, 17-inch wheels, 245 tyres, EIBACH PN# 2563.140 springs allowed. · GT2 Corvette -2019 LS6 allowed to reduce weight by 50 lbs. · T3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs. · GT2 Panoz GT-S may use TA2 Choice Engine with any 5-speed H-shift transmission. · GT2-ST Corvette LS2 restrictor increases from 70mm to 75mm flat plate; LSX block option added. · GT2-ST Corvette L76 added: 5967cc displacement, 3000 lb minimum weight, 70mm flat plate restrictor. · GT2 Porsche 991.2 GT3 Cup Car engine displacement corrected to 4.0L from 3.8L. · GT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications. · GT2 Chevrolet SS replaces Dodge Charger; all stock car bodies removed from GT2 in 2021. · Pontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18x9.5, Sky weight drops to 3200 lbs. · Mazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01. · GTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo. · 991.2 GT3 Cup Car added to GT2 at 3100 lbs with 63mm throttle body restrictor. · GT2 Acura NSX minimum weight cut from 3000 lbs 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 drops to 2800 lbs. · GT2 Corvette -2019 restrictor reduced from 75 mm to 70 mm. · T2 must have fire system installed; T3 and T4 may have one per GCR 9.3. · T3 Ford Mustang EcoBoost gains three transmission gear ratio options. · T3 and T4 Mazda RX-8 Base/R3 (04-12) reclassified to include Sport and GT variants. · Toyota 86 GT variant (2017–) added to T3 and T4 spec lines.showhide
GT2 rescind GT2 stock car bodies removal #29219cars addedaddedGT2 stock car bodies removal rescinded; 1997-current year commercially available stock car bodywork allowed.
GT2 E&O Typos in Appendix L #29447wordingwordingGT2 Appendix L section 4.8.4.2.10.3.6 renumbered, eliminating subsections .17–.19.
GT2 GT2 wing width wording correction #29469wordingwordingGT2 TA2 wing width maximum clarified to 65 -5/16 inches, including end plates.
SM Radiator E&O Clarifications #29294wordingwordingSM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A.
T3 Request to Classify Honda Civic Type R in T3 #27840cars added
GT2 GT Category Wording #29193wordingaddedGT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line.
GT2 997.2 E&O link to 27915 #29373weightfaster · weightGT2 997.2 GT3 Cup minimum weight reduced from 3000 to 2900 lbs.
GT2 Request for allowance Trans Am SGT #28951cars addedaddedGT2 BMW E46 M3, E36, Z3, and 5000cc V8 gain Trans Am SGT option: regular shifter 3000 lbs., paddle shifter plus 150 lbs.
GT2 Omitted GT2 fender/hood openings #29171aeroadded · aeroGT2 allows up to four hood/fender louvered panels, max 600 sq inches total, min five slots each, ahead of windscreen.
SM Modifications to prevent failures of Rear Brake Caliper Pin #28953suspension & brakessuspension & brakesSM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure.
T3 Request to classify 2009 Honda Accord v6 manual #28913cars added
GT2 TA2 Gurney flap wicker clarification #28874wordingwordingTA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications.
GT2 STO Gurney flap wicker clarification #28883wordingwordingSTO rear wing rules clarify that wicker is called Gurney flap in two places; no performance change.
GT2 GT Gurney flap wicker clarification #28909wordingwordingGT Gurney flap wording clarified: wickerbill and tab terminology replaced with Gurney flap throughout sections 9.1.2.F.7.b.
T3 Request for competition adjustment for the MK5 GTI FSI engine #28802engine
T3 Request to Add a Vehicle to the Roster (contd.) #27698wordingunclearRequest to add vehicle to T2, T3, T4 roster; refer to letter #27663 in June 2020 Fastrack for decision.
GT2 Request to Adjust Weight of OEM 8.4 Viper #28739weight -50 lbsfaster · weightGT2 Dodge Viper 8.4 OEM minimum weight reduced to 3275 lbs.
GT2 Request to Adjust Weight of OEM Chevrolet Corvette #28896weight -50 lbsfaster · weightGT2 Chevrolet Corvette -2019 OEM minimum weight reduced to 3275 lbs.
T3 Request to Classify 2004 Mercedes Benz 320 CLK #27663cars addedadded2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine, 17-inch wheels, 245 tyres, EIBACH PN# 2563.140 springs allowed.
T3 Request Nissan 350Z Part Number change #28145induction
GT2 Request Corvette engine parity #28576weightfaster · weightGT2 Corvette -2019 LS6 allowed to reduce weight by 50 lbs.
T3 2015 + Ford EcoBoost Mustang Sway Bars #28398suspension & brakes
T3 Z3M Roadster Weight #28437weightfaster · weightT3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs.
GT2 Request to revisit Panoz GT-S BoP #28280cars addedaddedGT2 Panoz GT-S may use TA2 Choice Engine with any 5-speed H-shift transmission.
GT2 Request 991.2 Porsche engine displacement verify typo #28194enginefaster · engineGT2 Porsche 991.2 GT3 Cup Car engine displacement corrected to 4.0L from 3.8L.
T3 Clarify 05-10 V8 Mustang Spring Rates Wording/Adjust Restrictor #28238induction
T3 Correct Touring 3 05-10 Mustang final drive #28288wording
GT2 Windshield Clips #27323otheraddedGT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications.
GT2 Request to Add Chevrolet SS Body to Appendix L #27898cars addedremoved · cars addedGT2 Chevrolet SS replaces Dodge Charger; all stock car bodies removed from GT2 in 2021.
T3 2006 BMW E90 330i Sedan Classification #26663weight
T3 Please Switch the Solstice GXP as Specified in T2, to T3 #27413cars added -50 lbsfaster · cars addedPontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18x9.5, Sky weight drops to 3200 lbs.
T3 Request to Classify all Mazda RX8 Models in T3/T4 #27606cars addedaddedMazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01.
T3 Request for 2005 Subaru STI Changes #27658tyres & wheels +50 lbs
T3 Request to Classify 2017 Ford Fiesta ST #27700cars added
GT2 Request Factory Five Daytona coupe classification #26308cars addedaddedGTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo.
GT2 Porsche 991.2 GT3 Cup GT2 Classification #27701cars addedadded991.2 GT3 Cup Car added to GT2 at 3100 lbs with 63mm throttle body restrictor.
GT2 Request for Acura NSX Spec Line Changes #27755weightfaster · weightGT2 Acura NSX minimum weight cut from 3000 lbs to 2700 lbs.
GT2 GT2 991.1 restrictor size change #27914enginefaster · engineGT2 Porsche 991.1 GT3 Cup restrictor size increases from 67 mm to 70 mm.
GT2 GT2 996/997.1 weight change #27915weight -100 lbsfaster · weightGT2 Porsche 996/997.1 GT3 Cup minimum weight drops to 2800 lbs.
GT2 GT2/ST Corvette comp adjustment #27920engineslower · engineGT2 Corvette -2019 restrictor reduced from 75 mm to 70 mm.
T3 Clarification of On-Board Fire System for T2 #27183wordingwordingT2 must have fire system installed; T3 and T4 may have one per GCR 9.3.
T3 Mustang Ecoboost and GT Transmission #27439cars addedaddedT3 Ford Mustang EcoBoost gains three transmission gear ratio options.
1:50.182Andrew Aquilante · fastest of 24 · top 5 within 4.5s
1:52.475Andrew Aquilante · fastest of 19 · top 5 within 3.3s
162.8Tom Patton
2:14.552Todd Buras · fastest of 60 · top 5 within 0.2s
2:16.459Elivan Goulart · fastest of 56 · top 5 within 0.4s
119.8Jim Drago
+23.984squal +24.370s
121.3%qual 122.1%
2:04.918Marshall Mast · fastest of 20 · top 5 within 1.1s
2:05.354Broderick Bauguess · fastest of 20 · top 5 within 1.6s
138.2Scotty B White
+12.879squal +14.736s
111.5%qual 113.4%
54 rule changes (GT2: 21, SM: 4, T3: 29)18 cars added · 10 weight · 4 suspension & brakes · 2 aero · 2 engine · 2 tyres & wheels · 10 wording · 6 other · T2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove. · GT2 TA2 cars must meet 2930 lbs minimum weight per current Trans Am rules or Appendix L. · GT2-ST Toyota Supra 3SGTE added: 2.0L, 2900 lbs minimum weight, 43mm restrictor. · Acura NSX all years classified to GT2-ST: 3.5L turbocharged, 3000 lbs minimum, 43mm restrictor, specific aero and turbo required. · GT2 TA2 minimum weight increases 100 lbs to 2930 pounds. · GT2 BMW E36/E46 M3 and Z3: 4.5L V8 permitted at 2950 lbs, 5.0L V8 at 3000 lbs, plus Flossman body kit allowed. · GTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. · GTX adds Ligier JS2 R classification with restrictor and minimum weight. · GT2 Ford Mustang 5.2L classified at 3300 lbs minimum weight, 82mm single throttle body, carbon fiber body parts allowed. · GT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate. · GT2/ST Porsche Cayman eligible model years extended from 2005–2011 to 2005–2015. · GT2 Porsche Cayman adds 4.0L with 65mm flat plate restrictor at 2700 lbs minimum weight. · SM fuel pump and filter now permitted as Mazda or OEM equivalent part. · T1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017. · 2015+ Subaru WRX classified in T3 at 1998cc, 3275 lbs minimum, 245/18 tires, 35mm turbo inlet restrictor required. · T4 and T3 Mazda MX-5 hardtop rules clarified: any OEM or aftermarket top permitted if retaining OEM silhouette; specific part numbers listed. · T3 Mazda MX-5 NC 06-15 wheel width increases from 7 to 8 inches. · T3 Mazda MX-5 NC 06-15 now allows any aftermarket header. · T3 Saturn Sky intercooler intake diameter increases to 35mm TIR; new calipers and spring rate limits added. · T2, T3, T4 now allow any thermostat serving original equipment intent only. · T3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years. · SM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified. · SM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted. · SM tire tread protrusion language removed from GCR 9.1.7.C.5. · T3 Mazdaspeed 3 07-09 front brake disc grows to 320mm vented, rear to 300mm solid. · GT2 BMW E46 M3, E36, Z3, and 5000cc V8 may now use Flossman body kit. · GT2 TA2 clarifies rules; shock caps to $850, brake calipers to $550, pads to $250/axle, wheels to $175 each; allows carbon fiber rear wing; engine setback 21.75 inches max (A–F) or 24 inches (G); carbureted engine displacement 366 cubic in… · GT2 adds BMW 1 Series E82 2008–2012 with N52B30 engine, 2996 cc, 2140 lbs minimum weight. · GT2 Porsche Cayman 05-11 minimum weight drops to 2800 lbs; STO and X51 motor variants noted at 2950 and 2850 lbs. · GT2 Ford Mustang 05- with Ford Racing 5.2l Aluminator engine classified: 5200cc displacement, 3400 lbs minimum weight, 2×41mm flat plate restrictor. · GT2 Porsche 996/997.1 GT3 Cup: add 3.6L displacement and 2900 lbs minimum weight; remove aftermarket exhaust header allowance for 996. · GT2 Ford Mustang FP350S minimum weight reduced 100 lbs to 3400. · GT2 Ford Mustang 05- EcoBoost added: 3500 cc, 3200 lbs minimum, 41 mm restrictor. · GT2 Mazda RX7 Downing GTS body kit allowed without 75 lbs. weight penalty. · GTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs. · T4 Celica GT wheelbase 2600 and 15x7 wheels added; Forte years narrowed; Fiesta ST starts 2014; Fiat 124 years 16-18 added; battery rule clarified. · T3 BMW SpecE46 must conform to Version 2.6 Effective Jan 1, 2019; Appendix N removed from GCR. · T3 Nissan 350Z 03-08 and Spec Z permitted to use Nissan brake kit part number 41000-BRKIT. · T1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications. · T2–T4 subframe bushings now permitted to be replaced with non-spherical bushings of any material. · T3: 24 cars lose 50–75 lbs across multiple models, including Camaro, Mustang, Miata, WRX, 370Z, GTI, and others. · T3 Ford Mustang EcoBoost gains two alternate brake kit options: Ford Motorsports 6-piston M2300V 380mm with 100lb penalty, or Brembo 2-piece 355mm rotor with 100lb penalty. · T3 FR-S/86 and BRZ: wheels to 17×9, tyres to 255, weight to 2750 lbs, final drive 4.10 or 4.30. · T3 BMW SpecE46 gains alternate tire option: any DOT up to 225 width permitted.showhide
T3 Request Mazda NC MX-5 alternate transmission gear ratios #27155other
T3 Request spare tire/wheel clarification #27012wordingfasterT2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove.
T3 Request guidance for 2014-2017 MK7 Volkswagen GTI #26866weight
GT2 TA2 Weight Clarification #27077weightslower · weightGT2 TA2 cars must meet 2930 lbs minimum weight per current Trans Am rules or Appendix L.
T3 Request BMW e36 M3 sway bar and links #26885suspension & brakes
GT2 Request to classify Toyota Supra with 3SGTE engine #25185cars addedaddedGT2-ST Toyota Supra 3SGTE added: 2.0L, 2900 lbs minimum weight, 43mm restrictor.
GT2 Request to Classify Acura NSX from T1 to GT2? #26121cars addedaddedAcura NSX all years classified to GT2-ST: 3.5L turbocharged, 3000 lbs minimum, 43mm restrictor, specific aero and turbo required.
GT2 Request for TA2 BOP in GT2 #26509weightslower · weightGT2 TA2 minimum weight increases 100 lbs to 2930 pounds.
T3 Request to properly class base Porsche Cayman #26276weight
GT2 Request for e36/e46 bmw 4500 cc v8 at 2950lbs in GT2/ST #26106cars addedaddedGT2 BMW E36/E46 M3 and Z3: 4.5L V8 permitted at 2950 lbs, 5.0L V8 at 3000 lbs, plus Flossman body kit allowed.
GT2 Request GTX Fuel injection for previous GT-1 tube frame cars #26141engineadded · engineGTX tube frame cars now allowed fuel injection with maximum 90mm throttle body.
GT2 Request to Classify Ligier JS2 R #26535cars addedaddedGTX adds Ligier JS2 R classification with restrictor and minimum weight.
T3 Request to classify a 2019 Chevrolet Camaro LT-I4 Turbo 1LE #25731cars added
T3 Class Civic Si 2017+ w/ alternate cage #26449cars added
T3 Classify 2014-2017 MK7 Volkswagen GTI for T3 #26695cars added
GT2 Request Ford Perfomance 5.2L crate engine FPR clarification #26159cars addedaddedGT2 Ford Mustang 5.2L classified at 3300 lbs minimum weight, 82mm single throttle body, carbon fiber body parts allowed.
GT2 Request Ride Height Clarification #26600wordingfasterGT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate.
T3 Request to allow E36 M3 in T3 prepared to BMWCCA I sport #25195cars added
GT2 Request Porsche Cayman year classification #26241cars addedaddedGT2/ST Porsche Cayman eligible model years extended from 2005–2011 to 2005–2015.
SM Request to allow aftermarket fuel filters. #26370otheraddedSM fuel pump and filter now permitted as Mazda or OEM equivalent part.
T3 Request Mustang GT Limited Prep 2018 Classification #24431cars addedaddedT1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017.
T3 Classify 2015+ WRX #25832cars addedadded2015+ Subaru WRX classified in T3 at 1998cc, 3275 lbs minimum, 245/18 tires, 35mm turbo inlet restrictor required.
T3 Correct Mazda MX-5 Hard Top Notes #26137wordingwordingT4 and T3 Mazda MX-5 hardtop rules clarified: any OEM or aftermarket top permitted if retaining OEM silhouette; specific part numbers listed.
T3 Request to allow T3 06-15 Miata 17x8 wheels #26161tyres & wheelsfaster · tyres & wheelsT3 Mazda MX-5 NC 06-15 wheel width increases from 7 to 8 inches.
T3 Request T3 06-15 Miata header #26162otheraddedT3 Mazda MX-5 NC 06-15 now allows any aftermarket header.
T3 Request Pontiac GXP same allowances to Saturn Sky #26175aeroadded · aeroT3 Saturn Sky intercooler intake diameter increases to 35mm TIR; new calipers and spring rate limits added.
T3 Consider opening class rules to allow any thermostat #26187engineadded · engineT2, T3, T4 now allow any thermostat serving original equipment intent only.
T3 Cap 2016 Mazda Miata year at 2018 #26388cars addedremoved · cars addedT3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years.
SM Request 99-00 replacement Wire harnesses #25602otheraddedSM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified.
SM Organize and Clarify 9.1.7.C.1.o. #25913wordingwordingSM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted.
SM Strike Tire Tread Language #26123wordingremovedSM tire tread protrusion language removed from GCR 9.1.7.C.5.
T3 Request correction on brake sizes #26170suspension & brakessuspension & brakesT3 Mazdaspeed 3 07-09 front brake disc grows to 320mm vented, rear to 300mm solid.
GT2 ST/GT2 BMW Flossman Kit Clarification #22138aeroadded · aeroGT2 BMW E46 M3, E36, Z3, and 5000cc V8 may now use Flossman body kit.
GT2 Request Clarification/Revision of Appendix L (2013 TA2 Rules) #25110wordingwordingGT2 TA2 clarifies rules; shock caps to $850, brake calipers to $550, pads to $250/axle, wheels to $175 each; allows carbon fiber rear wing; engine setback 21.75 inches max (A–F) or 24 inches (G); carbureted engine displacement 366 cubic in…
GT2 Request to classify BMW E82 (1 series) into GT2 #25539cars addedaddedGT2 adds BMW 1 Series E82 2008–2012 with N52B30 engine, 2996 cc, 2140 lbs minimum weight.
GT2 2010 Cayman Street Tuner Into an STO Car,Addendum #25545weightfaster · weightGT2 Porsche Cayman 05-11 minimum weight drops to 2800 lbs; STO and X51 motor variants noted at 2950 and 2850 lbs.
GT2 Request - Classify Ford Performance 5.2l #25716cars addedaddedGT2 Ford Mustang 05- with Ford Racing 5.2l Aluminator engine classified: 5200cc displacement, 3400 lbs minimum weight, 2×41mm flat plate restrictor.
GT2 Request for Ford FP 350s Weight Reduction #25806weightfaster · weightGT2 Ford Mustang FP350S minimum weight reduced 100 lbs to 3400.
GT2 Request to Classify EcoBoost Mustang #25842cars addedaddedGT2 Ford Mustang 05- EcoBoost added: 3500 cc, 3200 lbs minimum, 41 mm restrictor.
GT2 Request to Remove Mazda RX 7 Body Work Penalty #26024weightfaster · weightGT2 Mazda RX7 Downing GTS body kit allowed without 75 lbs. weight penalty.
GT2 GTX Homologation table update #26034otherunclearGTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs.
T3 Errors, Omissions, and Updates (Various) #22414wordingwordingT4 Celica GT wheelbase 2600 and 15x7 wheels added; Forte years narrowed; Fiesta ST starts 2014; Fiat 124 years 16-18 added; battery rule clarified.
T3 Request to update SpecE46 Appendix N. with 2019 Rules #25722wordingunclearT3 BMW SpecE46 must conform to Version 2.6 Effective Jan 1, 2019; Appendix N removed from GCR.
T3 Request Alternative Nissan Brake Parts - 350Z #25747otheraddedT3 Nissan 350Z 03-08 and Spec Z permitted to use Nissan brake kit part number 41000-BRKIT.
T3 Add Clarification to Spec Car Classifications Vehicle Spec #25774wordingwordingT1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications.
T3 Clarify Subframe Bushings Permitted for T2-T4 #25800suspension & brakesadded · suspension & brakesT2–T4 subframe bushings now permitted to be replaced with non-spherical bushings of any material.
T3 Additional weight adjustments for T3 cars T3 weight loss #25803weightfaster · weightT3: 24 cars lose 50–75 lbs across multiple models, including Camaro, Mustang, Miata, WRX, 370Z, GTI, and others.
T3 Request for Alternate EcoBoost Mustang Brakes #25813suspension & brakesadded · suspension & brakesT3 Ford Mustang EcoBoost gains two alternate brake kit options: Ford Motorsports 6-piston M2300V 380mm with 100lb penalty, or Brembo 2-piece 355mm rotor with 100lb penalty.
T3 Request to Add the FR-S/86 and BRZ Spec Lines to T3 #25888weightfaster · weightT3 FR-S/86 and BRZ: wheels to 17×9, tyres to 255, weight to 2750 lbs, final drive 4.10 or 4.30.
T3 Request to Clarify BMW SpecE46 Tire Verbiage #26027tyres & wheelsadded · tyres & wheelsT3 BMW SpecE46 gains alternate tire option: any DOT up to 225 width permitted.
Every event the class ran, at any track, oldest to newest on the chart and newest first in the table. Each point is the class's best lap as a share of GT2's best on the same day: the weather, the track and its configuration cancel out, so one figure compares across tracks and years where lap times cannot. It still moves when the yardstick's own balance changes or its field thins, and an event the yardstick did not run has no point. A best from fewer than three cars is greyed. The rule changes that took effect between two events are folded between their rows.