Quickest here:T2 1:33.964 Chip Herr, Great Lakes Champions 2026 qualifying · GT3 1:38.003 Michael Lewis, Great Lakes Champions 2024 qualifying
T2GT3solid race · dashed qualifying · slower is lower
T2GT3solid race · dashed qualifying · each class's best lap as a share of T2's at the same event (the reference class, changeable above); 100% is level, higher is quicker
Event
T2
GT3
Qual best
Race best
Trap
Qual best
Race best
Trap
vs T2
% of T2
Great Lakes Champions 2026 GREALA262026-05-15
1:33.964Chip Herr · fastest of 6 · top 5 within 3.9s-2.596s (-2.69%)
1:35.081Chip Herr · fastest of 6 · top 5 within 3.1s-0.740s (-0.77%)
136.4Chip Herr-1.5 mph (-1.1%)
28 rule changes (T2: 25, GT3: 3)6 weight · 5 suspension & brakes · 4 cars added · 3 engine · 2 induction · 1 aero · 7 wording · T2 BMW 435i brakes increased from 340/330mm to 370/345mm front and rear. · T2 Porsche Cayman S year ranges and engine specs adjusted for 2026; multiple model years and displacements updated. · T2 TCR adds 2024 WSC TCR Technical Regulations conformance requirement, clarifies ballast fastening, limits wheels to 10x18 inches and tyres to 275 max width. · GT3U class removed from GCR; GT3U cars now run in STU with 3.0" main frame and 2" front spoiler minimum ride height. · T2 BMW M235iR pre-2016 alternative tune permitted note removed. · BMW 435i (2014-2017) added to T2 with 40mm restrictor, 3400 lbs minimum weight. · Nissan Z including Nismo added to T2 with 38mm restrictor, 3600 lbs base and 3650 lbs Nismo. · T2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously prohibited except in specified examples. · T2-TCR adds Link & Co 03 TCR and MG6 TCR, both 3000 lbs, 90% power, 275 max tire width. · GT3U cars must maintain 3.0" minimum ride height on frame rails and 2" minimum on front spoiler and splitter. · T2, T3, T4 cars may relocate under-dash electronics and fuse boxes for access after roll cage installation. · T2 Cadillac CT4-V Blackwing minimum weight drops 50 lbs to 3750. · T2 C6 Corvette LS2 restrictor increases from 67mm to 80mm FPR. · T2 Dodge Viper SRT10 coupe weight reduced from 3675 lbs to 3650 lbs. · T2 Ford Mustang GT 5.0L 15-23 permits Ford Track/Performance Package aero parts M-16600-FP and M-16601-MPP. · T4 Performance now permits 1-piece alternative rotors matching spec line sizes; alternate brake kits allowed same. · T2 Ford Mustang Boss 302 restrictor opens 56mm to 63mm; Mustang GT 5.0L 60mm to 65mm. · T2 Chevrolet Camaro SS/1LE (10-15) minimum weight reduced to 3575 lbs. · T2 Ford Mustang Challenge Dark Horse R (2024-) weight increases to 3825 lbs, displacement grows to 5038cc, tire width expands to 315. · T3 and T4 Mazda MX-5 Miata models add approved gear kit PT#-0000-02-6100 to notes. · T4 Mazda MX-5 Miata/Club/RF (19-24) and (16-18) remove discontinued hardtop part #0000-07-5901; T3 MX-5 Miata (16-18) and Global Cup ND (16-21) same. · T2 Spec Corvette to 3200 lbs; Mustang 11-14 restrictor 60→62mm; Mustang 2015-23 tyre 295→315; 996 weights down to 3050/3000 lbs; 997.2 models restrictor 60→65mm, weights reduced 50 lbs. · T2 Spec Corvette rev limit set to 7100 rpm. · GT3U cars with 15×7" wheels add 225 lbs to GT3 weight; wider wheels allowed with weight penalties up to 3.0%. · T2, T3, T4 Spec Lines table header changed from T2 to ET. · BMW M2 CS Cup 2020 must run Red power stick part #8324085, not Purple #8324089. · T2 Chevrolet Corvette C5 Z06 and C6 brake allowances clarified; stock calipers and rotors only for C5, specific sizes for C6. · T2 Chevrolet Corvette C5 LS1 restrictor reduced from 59mm to 58mm FPR.showhide
T2 14-17 BMW 435i Brake Approval Request #39910suspension & brakesfasterT2 BMW 435i brakes increased from 340/330mm to 370/345mm front and rear.
T2 Porsche Cayman S Spec Lines Needed for Atlanta HST #39947wordingneutralT2 Porsche Cayman S year ranges and engine specs adjusted for 2026; multiple model years and displacements updated.
T2 Please address loopholes in T2 TCR #40002wordingneutralT2 TCR adds 2024 WSC TCR Technical Regulations conformance requirement, clarifies ballast fastening, limits wheels to 10x18 inches and tyres to 275 max width.
GT3 Remove GT3U from GCR as it is now in STU #39862cars addedneutralGT3U class removed from GCR; GT3U cars now run in STU with 3.0" main frame and 2" front spoiler minimum ride height.
T2 BMW 240i Permitted Tune #39861wordingunclearT2 BMW M235iR pre-2016 alternative tune permitted note removed.
T2 Request to Add 2014-2017 435i to T2 #38991cars addedneutralBMW 435i (2014-2017) added to T2 with 40mm restrictor, 3400 lbs minimum weight.
T2 Consideration for Nissan Z & NISMO Z to Touring 2 Class #39296cars addedneutralNissan Z including Nismo added to T2 with 38mm restrictor, 3600 lbs base and 3650 lbs Nismo.
T2 Allow Alt Bushing Material in Toe Links #39607suspension & brakesfasterT2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously prohibited except in specified examples.
T2 Request for Classification of MG6 TCR in T2-TCR Class #39702cars addedneutralT2-TCR adds Link & Co 03 TCR and MG6 TCR, both 3000 lbs, 90% power, 275 max tire width.
GT3 GT3U Ride Height #39637suspension & brakesneutralGT3U cars must maintain 3.0" minimum ride height on frame rails and 2" minimum on front spoiler and splitter.
T2 Alternate Placement of Fuse Panel and Electronics Request #39370wordingneutralT2, T3, T4 cars may relocate under-dash electronics and fuse boxes for access after roll cage installation.
T2 Rebalance Blackwing Cadillac T2 for 2026 #39426weight -50 lbsfasterT2 Cadillac CT4-V Blackwing minimum weight drops 50 lbs to 3750.
T2 C6 LS2 Corvette Parity Request #39472inductionfasterT2 C6 Corvette LS2 restrictor increases from 67mm to 80mm FPR.
T2 T2 Tire Sizing #39490weight -25 lbsfasterT2 Dodge Viper SRT10 coupe weight reduced from 3675 lbs to 3650 lbs.
T2 Rear Spoiler for Mustang GT S550 (15-23) #39499aerounclearT2 Ford Mustang GT 5.0L 15-23 permits Ford Track/Performance Package aero parts M-16600-FP and M-16601-MPP.
T2 Clarify T4 Brake Rotor Allowance #39503suspension & brakesneutralT4 Performance now permits 1-piece alternative rotors matching spec line sizes; alternate brake kits allowed same.
T2 Help the 2011-2014 s197Mustang GT and Boss302 Less Restriction #38523inductionfasterT2 Ford Mustang Boss 302 restrictor opens 56mm to 63mm; Mustang GT 5.0L 60mm to 65mm.
T2 Improving Competitiveness of Gen 5 Camaro SS #39021weight -50 lbsfasterT2 Chevrolet Camaro SS/1LE (10-15) minimum weight reduced to 3575 lbs.
T2 Adjust T2 Darkhorse R #39346weightslowerT2 Ford Mustang Challenge Dark Horse R (2024-) weight increases to 3825 lbs, displacement grows to 5038cc, tire width expands to 315.
T2 ND Gearset Request for T4 #39166wordingneutralT3 and T4 Mazda MX-5 Miata models add approved gear kit PT#-0000-02-6100 to notes.
T2 ND Spec Lines Wrong PT#'s #39170wordingneutralT4 Mazda MX-5 Miata/Club/RF (19-24) and (16-18) remove discontinued hardtop part #0000-07-5901; T3 MX-5 Miata (16-18) and Global Cup ND (16-21) same.
T2 Touring 2 Post-Runoffs BOP Adjustments and Changes #39274weight -50 lbsfasterT2 Spec Corvette to 3200 lbs; Mustang 11-14 restrictor 60→62mm; Mustang 2015-23 tyre 295→315; 996 weights down to 3050/3000 lbs; 997.2 models restrictor 60→65mm, weights reduced 50 lbs.
T2 Adjust rev limit on Spec Corvette in T2 #39282engineslowerT2 Spec Corvette rev limit set to 7100 rpm.
GT3 Declassify TCR Cars from GT3/GT3U #38569weightslowerGT3U cars with 15×7" wheels add 225 lbs to GT3 weight; wider wheels allowed with weight penalties up to 3.0%.
T2 Incorrect Touring Heading #38451wordingneutralT2, T3, T4 Spec Lines table header changed from T2 to ET.
T2 Clarifications needed to BMW M2 CS cup line #38536engineunclearBMW M2 CS Cup 2020 must run Red power stick part #8324085, not Purple #8324089.
T2 Fix brake allowance supersessions. #38554suspension & brakesslowerT2 Chevrolet Corvette C5 Z06 and C6 brake allowances clarified; stock calipers and rotors only for C5, specific sizes for C6.
T2 C5 Corvette correction #38782engineslowerT2 Chevrolet Corvette C5 LS1 restrictor reduced from 59mm to 58mm FPR.
Ohio Valley Great Lakes Champions 2025 OHIOVA252025-05-16
1:36.560Aaron Kaplan · fastest of 3 · top 3 within 0.3s
1:35.821Basam Abdallah · fastest of 3 · top 3 within 1.6s-0.966s (-1.00%)
137.9Scotty B White
48 rule changes (T2: 33, GT3: 15)13 weight · 8 cars added · 4 induction · 3 tyres & wheels · 2 engine · 2 removed · 2 suspension & brakes · 11 wording · 3 other · GT3U with 15x7 wheels and 225 tires gains 75 lbs to 225 lbs over GT3 weight; wheel weight penalties clarified. · T2 C6 Corvette LS2 restrictor increases from 63mm to 67mm FPR. · T2 Nissan 370Z max wheel size increases to 19 x 10.5 inches; mid link replacement for true coil overs now permitted. · T2 Cadillac CT4-V Blackwing maximum tire size increases from 295 to 315. · Ford Mustang Challenge Darkhorse R newly classified in T2 with 58 mm restrictor, 3775 lbs minimum weight. · T2 350Z (03-08) removes detailed OEM part numbers and consolidates permitted modifications into simplified allowance list. · T2 BMW M2 CS Cup requires Red power stick #8324085 instead of Purple #8324089; Corvette C5 Z06 restrictor reduces to 58mm from 59mm. · T2 Mustang GT 5.0L combines 2015-17 and 2018-23 with different restrictors: 63mm for Gen 2, 60mm for Gen 3. · T2 Chevrolet Camaro 1LE gains 100 lbs to 3600, restrictor increases to 62mm FPR. · T2 BMW M235iR (-2016) now permits oil cooler, radiator per touring rules, and silicone charge pipe. · Ford SCCA Club Spec Mustang classified T3 at 3350 lbs with driver; Mazda SCCA Club Spec MX-5 classified T4 at 2500 lbs with driver. · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof requirement. · GT3 VW Fun Cup Beetle Sealed exempt from 150 lbs consolidation add-on weight. · T2, T3, T4 remove nine, nine, and thirty-six expired spec lines respectively, effective 2025-01-01. · T2 Ford Mustang GT 5.0L (11-14) weight reduced from 3575 to 3525 lbs. · T2 Spec Corvette clarifies braking, tires, cooling, suspension, and Spec+ upgrades; SC-3200, SC+-3300 lbs. · GT3 Pontiac LE5 Ecotech minimum weight drops 150 lbs to 2195. · T2 and T3 Mustang spec lines remove redundant driveshaft alternate/aluminum allowance wording. · T2 Chevrolet Corvette C6 LS3 restrictor increases from 53mm to 56mm flat plate. · T2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors. · T2, T3, T4 brake component wording clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter. · T2, T3, T4 fuel cell cars may remove charcoal canisters, emissions valves, and sensors. · Porsche Spec Boxster moves to T4, minimum weight 2750 lbs, requires 3 Super Tour events before Runoffs eligibility. · T2 Chevrolet Corvette C6 Coupe/Grand Sport wheels widened to 18×11 or 19×13. · T4 BMW 320i 14-15 Spec Line expires 12/31/24 removed; Turner Motorsports intercooler #024703TMS02 allowed. · Cadillac CTS 02-07 3.6L classified in T3. · T2 Corvette C5 Z06 restrictor split by engine: LS1 59mm, LS2 63mm, LS3 56mm FPR. · T2 Chevrolet Corvette Z06 (06-12) Spec Line deleted entirely. · GT3 Mazda 13B Bridgeport and Peripheral Port both drop to 2275 lbs minimum weight. · GT3 Nissan MR20DE DOHC engine classified with 1997cc displacement, 32mm restrictor, 2060 lbs minimum weight. · GT3 Mazda 13B minimum weight drops 175 lbs to 2175 lbs. · GT3 Mazda 12A peripheral port minimum weight reduced to 2100 lbs. · T2 Spec Corvette now allows 295 R compound DOT tires as alternative to Nankang NS-2R. · GT3 Mazda 3TC classified in TCR with 2950 lbs minimum weight, effective 11/1/2024. · GT3 adds Datsun 1200 B110 (70–73), 90.6 in wheelbase, engine per GT3 spec or alternate Nissan request. · GT3-TCR Honda Civic Type R, Audi RS3 LMS, Hyundai I30N, Volkswagen GTI weights adjusted; Hyundai down 100 lbs to 3154, VW down 100 lbs to 3077. · T2 Corvette C6 LS2 restrictor increases to 63mm; Camaro 1LE weight drops to 3500 lbs, restrictor tightens to 58mm FRP. · T2 Subaru Impreza WRX STi (03-07) and (08-11) expiration notes removed. · T2 Ford Mustang 5.0L gets 100 lb weight reduction with 4-piston Brembo brakes and 355mm rotors; EcoBoost brake note removed. · GT3 Pontiac Sunfire GT weight reduction corrected from 150 lbs to 75 lbs. · GT3 Mazda MZR removes second DOHC option, fuel induction now unrestricted. · Ford Mustang GT 5.0L and V6 now permit Track/Performance Package parts in T2 and T3. · T2 Ford Mustang S550 5.0 Gen2/Gen3 gains 100 lbs with stock or Brembo 355mm brakes. · T2-T4 Ford Mustangs: remove 25 lbs penalty for non-OEM driveshaft, clarify alternate driveshaft allowances. · T2 Corvette C5, Camaro SS, Firebird, Solstice GXP, C6 allow four or six piston front calipers. · Audi S4 (2000-2002) moves to T3 with 3400 lbs minimum weight, 38mm turbo inlet restrictor required. · GT3 cars may run +1mm SIR above spec with 175 lb weight penalty added. · GT3 turbocharged 1401-1850cc four-valve engine with 35mm restrictor reduced to 34mm, weight to 2250 lbs.showhide
GT3 Clarification of GT3U #38266weightslowerGT3U with 15x7 wheels and 225 tires gains 75 lbs to 225 lbs over GT3 weight; wheel weight penalties clarified.
T2 C6 T-2 Corvette 6 Liter Engine Restrictor #37490inductionfasterT2 C6 Corvette LS2 restrictor increases from 63mm to 67mm FPR.
T2 370Z Mid link Replacement for True Coil Overs and OEM Wheel Size #38014suspension & brakesfasterT2 Nissan 370Z max wheel size increases to 19 x 10.5 inches; mid link replacement for true coil overs now permitted.
T2 T2 Cadillac tire #38210tyres & wheelsfasterT2 Cadillac CT4-V Blackwing maximum tire size increases from 295 to 315.
T2 Please class the Darkhorse R in T2 #37295cars addedneutralFord Mustang Challenge Darkhorse R newly classified in T2 with 58 mm restrictor, 3775 lbs minimum weight.
T2 T2 350Z Spec Line Cleanup #37603wordingneutralT2 350Z (03-08) removes detailed OEM part numbers and consolidates permitted modifications into simplified allowance list.
T2 T2 BOP #37312otherslowerT2 BMW M2 CS Cup requires Red power stick #8324085 instead of Purple #8324089; Corvette C5 Z06 restrictor reduces to 58mm from 59mm.
T2 Mustang Update backdate #37275inductionunclearT2 Mustang GT 5.0L combines 2015-17 and 2018-23 with different restrictors: 63mm for Gen 2, 60mm for Gen 3.
T2 BOP Adjustment for 2016 - Camaro SS/1LE #37434weight +100 lbsslowerT2 Chevrolet Camaro 1LE gains 100 lbs to 3600, restrictor increases to 62mm FPR.
T2 BMW M235iR TCS CHANGE REQUEST #37470wordingneutralT2 BMW M235iR (-2016) now permits oil cooler, radiator per touring rules, and silicone charge pipe.
T2 Request to Classify Club Spec in Appropriate Touring Classes #37523cars addedneutralFord SCCA Club Spec Mustang classified T3 at 3350 lbs with driver; Mazda SCCA Club Spec MX-5 classified T4 at 2500 lbs with driver.
GT3 Correct language regarding OEM Areo Devices #37137wordingneutralTA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof requirement.
GT3 VW Funcap weight #37217weightfasterGT3 VW Fun Cup Beetle Sealed exempt from 150 lbs consolidation add-on weight.
T2 Remove spec lines that have expired #37269removedneutralT2, T3, T4 remove nine, nine, and thirty-six expired spec lines respectively, effective 2025-01-01.
T2 BoP for the Various Mustangs #37185weight -50 lbsfasterT2 Ford Mustang GT 5.0L (11-14) weight reduced from 3575 to 3525 lbs.
T2 Spec Corvette Line Clarification. #37441wordingneutralT2 Spec Corvette clarifies braking, tires, cooling, suspension, and Spec+ upgrades; SC-3200, SC+-3300 lbs.
GT3 Pontiac Weight and Chassis Adjustment Request #36938weight -150 lbsfasterGT3 Pontiac LE5 Ecotech minimum weight drops 150 lbs to 2195.
T2 Redundant Verbiage Regarding Mustang Spec Lines for Driveshaft #36484wordingneutralT2 and T3 Mustang spec lines remove redundant driveshaft alternate/aluminum allowance wording.
T2 Request Less Restriction for Ls-3 Engined C6 Corvette #36810inductionfasterT2 Chevrolet Corvette C6 LS3 restrictor increases from 53mm to 56mm flat plate.
T2 Fuel Emissions Components #37076wordingneutralT2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors.
T2 fix brake wording #37129wordingneutralT2, T3, T4 brake component wording clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter.
T2 Evaporative emissions systems #37130wordingneutralT2, T3, T4 fuel cell cars may remove charcoal canisters, emissions valves, and sensors.
T2 Move Spec Boxster to T4 #37158cars addedneutralPorsche Spec Boxster moves to T4, minimum weight 2750 lbs, requires 3 Super Tour events before Runoffs eligibility.
T2 Corvette Wheels #37169tyres & wheelsfasterT2 Chevrolet Corvette C6 Coupe/Grand Sport wheels widened to 18×11 or 19×13.
T2 BMW 320i Spec Line #37204wordingneutralT4 BMW 320i 14-15 Spec Line expires 12/31/24 removed; Turner Motorsports intercooler #024703TMS02 allowed.
T2 Classification for a 2005 Cadillac CTS 3.6 liter 6 speed manual #37224cars addedneutralCadillac CTS 02-07 3.6L classified in T3.
T2 Please Consider Allowing Update to the C5 Corvette #37298engineunclearT2 Corvette C5 Z06 restrictor split by engine: LS1 59mm, LS2 63mm, LS3 56mm FPR.
T2 Major error in lane, but nobody ran it. #37302removedneutralT2 Chevrolet Corvette Z06 (06-12) Spec Line deleted entirely.
GT3 GCR GT3 Disfranchised GT2 #36291weight -75 lbsfasterGT3 Mazda 13B Bridgeport and Peripheral Port both drop to 2275 lbs minimum weight.
GT3 GT3 Mazda12A PP Correction #37058weight -200 lbsfasterGT3 Mazda 12A peripheral port minimum weight reduced to 2100 lbs.
T2 Spec Corvette Change for T2 #37127tyres & wheelsneutralT2 Spec Corvette now allows 295 R compound DOT tires as alternative to Nankang NS-2R.
GT3 2024 Mazda 3 TC request for GT3 #36517cars addedneutralGT3 Mazda 3TC classified in TCR with 2950 lbs minimum weight, effective 11/1/2024.
GT3 Adding Datsun B110 to List of Approved Cars #36198cars addedneutralGT3 adds Datsun 1200 B110 (70–73), 90.6 in wheelbase, engine per GT3 spec or alternate Nissan request.
GT3 Honda Civic Type R TCR Weight Reduction Request #36550weightfasterGT3-TCR Honda Civic Type R, Audi RS3 LMS, Hyundai I30N, Volkswagen GTI weights adjusted; Hyundai down 100 lbs to 3154, VW down 100 lbs to 3077.
T2 Errors #36214other -75 lbsunclearT2 Corvette C6 LS2 restrictor increases to 63mm; Camaro 1LE weight drops to 3500 lbs, restrictor tightens to 58mm FRP.
T2 Subaru Appeal #36258wordingneutralT2 Subaru Impreza WRX STi (03-07) and (08-11) expiration notes removed.
T2 S550 Brakes #36571otherfasterT2 Ford Mustang 5.0L gets 100 lb weight reduction with 4-piston Brembo brakes and 355mm rotors; EcoBoost brake note removed.
GT3 Correct missed Disenfranchised weight reduction #36237weightfasterGT3 Pontiac Sunfire GT weight reduction corrected from 150 lbs to 75 lbs.
GT3 errors & omissions on GT3 Mazda MZR spec lines #36241enginefasterGT3 Mazda MZR removes second DOHC option, fuel induction now unrestricted.
T2 Mustang T2/T3 #35877wordingunclearFord Mustang GT 5.0L and V6 now permit Track/Performance Package parts in T2 and T3.
T2 S550 Brakes #35926weightslowerT2 Ford Mustang S550 5.0 Gen2/Gen3 gains 100 lbs with stock or Brembo 355mm brakes.
T2 T2-T4 Driveshaft Mistake...? #36050weightfasterT2-T4 Ford Mustangs: remove 25 lbs penalty for non-OEM driveshaft, clarify alternate driveshaft allowances.
T2 request for allowance of 6 piston calipers for T2 C5 corvettes #36126suspension & brakesfasterT2 Corvette C5, Camaro SS, Firebird, Solstice GXP, C6 allow four or six piston front calipers.
T2 B8/8.5 Audi S4 T3 and T2 #36195cars addedneutralAudi S4 (2000-2002) moves to T3 with 3400 lbs minimum weight, 38mm turbo inlet restrictor required.
GT3 GT3 +1mm SIR add 175lbs. In #36098weightslowerGT3 cars may run +1mm SIR above spec with 175 lb weight penalty added.
GT3 Revised GT3 Built Turbocharged chart #36100inductionslowerGT3 turbocharged 1401-1850cc four-valve engine with 35mm restrictor reduced to 34mm, weight to 2250 lbs.
Great Lakes Champions 2024 GREALA242024-05-17
1:36.787John Heinricy · fastest of 2
1:38.003Michael Lewis · fastest of 4 · top 4 within 9.0s
1:38.834Armen Megregian · fastest of 4 · top 4 within 0.9s
+2.047s
102.1%
224 earlier rule changes on record, in force before Great Lakes Champions 2024 (from 2019)48 cars added · 36 weight · 23 suspension & brakes · 22 induction · 10 aero · 10 tyres & wheels · 9 engine · 1 removed · 59 wording · 6 other · GT2-ST Acura NSX minimum weight raised to 3000 lbs, restrictor increased to 45mm TIR. · GT3 Ford Duratech now allows hood bulge with no openings. · GT3 Acura K20A RSX body disenfranchised from GT2 adds 75 lbs weight penalty. · GT3 Toyota 4Y engine classified at 2030 lbs with unrestricted fuel induction. · GT3 Toyota model designation changes from DR86 to GR86. · GT3 Honda spec lines change engine family designation from bore/displacement to K20C1 and K24 model numbers. · GT3 Mazda spec line numbering changed from 4 to Model, unrestricted to 323, and 2195 to 626. · T3 and T4 Mazda RX-8 may remove or disable factory oil injection system. · T2 BMW M3 01-06 max wheel size increases from 18 x 9 to 18 x 10 inch. · T2, T3, T4 driveshafts may use alternative materials or one-piece units; non-OEM adds 25 lbs. · T2 Porsche Cayman S 06-09 allows StopTech ST60/ST40 brake kit with 50 lb penalty. · GT3 Miata Turbo restrictor increases to 35 mm, minimum weight rises to 2350 lbs. · T2-T4 Spec Lines remove wheelbase requirement, replace with Required Restrictor specification. · T2 and T3 Nissan 370Z brake rotors enlarged: front 320x28 to 355x32mm, rear 320x16 to 350x20mm vented. · T2 Mustang GT 5.0L 2018+ now permits BMR rear upper control arm camber links part #UTCA064. · 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. · GT3 Toyota FA24D engine classified: 2387cc DOHC, 2195 lbs, 32mm SIR, direct injection permitted. · GT2/3 Nissan, Mazda, Mitsubishi 4G93, QR25DE/DD, QE25DE/DD Direct Injection now permitted per 9.1.2.F.7.5.E. · GT3 Nissan QR25DE/DD spec line edit; text unreadable due to formatting corruption. · T2 Mustang GT 5.0L 15-17 now permits BMR rear upper control arm camber links part #UTCA064. · T2 Chevrolet Camaro SS, 1LE, Corvette C5/C6, Z06, and Pontiac Firebird, Solstice GXP now allow four or six piston front calipers. · T2 Cadillac CT4-V Blackwing Runoffs qualification requirement removed. · T2, T3, T4 battery replacement wording simplified; OEM weight tolerance requirement removed. · T4 now permits C-Spec cars to compete alongside B-Spec cars. · T2-T4 spec lines for 46 cars expire 12/31/24; appeal required to continue. · T2 Chevrolet Camaro 1LE minimum weight increases to 3575 lbs, restrictor plate widens to 60mm. · GT3 Mazda RX7 12A, 13B Bridgeport, 13B Peripheral Port: disenfranchised GT2 adds 75 lbs. · GT3 Mazda BP4W turbocharged OEM engine weight reduced from 2060 to 1960 lbs. · GT3 Mazda 13B peripheral port weight reduced to 2100 lbs. · GT3 adds Toyota GR 86 (DR86) 2021–2024, 2-door RWD, 101.3 in wheelbase. · GT3 Toyota 3S bore increases to 86.0mm, stroke decreases to 86.0mm. · T2 Cadillac CT4-V Blackwing rear wheels widen from 18 x 10 to 18 x 11. · T2 BMW M2 CS Cup drops 50 lbs to 3550; M235iR drops 50 lbs to 3300. · T2 Spec Corvette minimum weight drops 175 lbs to 3200, tire rules tighten to Nankang NS-2R only. · T2 Dodge Viper SRT-10 rear tyre narrowed from 345/30 to 335/30. · T2 Ford Mustang GT 5.0L three generations gain 50-75 lbs minimum weight; restrictors increase to 58-60mm. · T2 Chevrolet Camaro 1LE minimum weight drops 50 lbs to 3500, restrictor opens to 58mm flat plate. · T2 C5 Z06 removes restrictor note from weight; C5/C6 Corvettes increase restrictors to 59mm, 63mm LS2, 53mm LS3. · T3 Nissan 370Z model years expanded to include NISMO Edition through 2022. · GT3 Toyota 3S DOHC engine classified at 1998 cc, 1960 lbs minimum weight, unrestricted fuel induction. · GT3 2.0L SIR cars lose 32mm unrestricted option, now require restrictor at 2195lbs minimum. · GTL spec lines moved to contiguous position with GT2 and GT3; GTA category and spec lines renumbered and moved behind GTL. · T2 BMW M2 CS Cup 2020- permitted to add hood vents conforming to 9.1.9.2.D.8.a.7. · GT3-TCR Audi RS3 LMS, Honda Civic Type R, Hyundai i30 N, VW Golf GTi must use 200 tread wear tires only. · GT3 Honda B20 engine newly classified for use in CRX, 1973cc displacement, aluminum head, DOHC. · GT3 cars using 15" American Racer 23.5-10.0-15 bias ply tires avoid weight penalty. · T2 Chevrolet Corvette C6 LS2 restrictor plate increases from 58mm to 60mm flat plate. · T2 Cadillac CT4-V Blackwing permitted to use Radium fuel surge tank behind fireproof bulkhead. · T3 Mazda RX-8 removes transmission/final drive pairing requirement; T4 removes same requirement, adds Mazdaspeed radiator and coil spring kit. · T3 BMW 320i (14-15) gains aftermarket intercooler permission; T4 loses it. · T3 Pontiac Solstice GXP minimum ride height set to 3 inches. · T2 Nissan 370Z allows NISMO suspension alternatives to SPL parts; rear toe arms removed from permitted list. · T2 Porsche Cayman S model year range extended from 06-08 to 06-09. · Fields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight. · T2 Chevrolet Corvette C5 Z06 restrictor increases from 53mm to 56mm; 58mm option removed. · T2 upper and lower control arm bushings can now use polyurethane, delrin, or alternate synthetic materials. · T2 Cadillac CT4-V Blackwing now permits adjustable sway bar end links. · T2 Honda Civic Type-R tire size increases from 275 to 295. · T2 C5 Corvette permitted GM Motorsports T1 suspension package and SpecCorvette SCT-1 swaybars. · T2/T3 Mustang GT 5.0L and V6 (11-14) may remove upper grille fog lights, replace with mesh or screen. · GT3 Nissan VG30 engine removed from class entirely. · 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. · T2 BMW M235iR weight reduced 50 lbs to 3350, aftermarket shocks now allowed. · T5 class added as regional-only; T5 tyres maximum width 225, minimum aspect ratio 45. · T2-T5 Touring front and rear suspension maximum negative camber changed to 3.5 degrees. · GT3 Mazda BP4W Turbocharged OEM engine added at 2060 lbs with 34mm TIR and IHI RHF5 VJ35 turbocharger. · GT2 TA2 and GTA throttle body part numbers updated to GM 90mm electronic #12570790 or Edelbrock 90mm mechanical #33869 or #3870. · GT3 Nissan SR20VET turbo changes to GT2860RS and allows open ECU instead of OEM stock. · T2 Dodge Viper SRT-10 wheel size 18x11 rear, weight to 3675 lbs, throttle restrictor hole 44mm convertible or 42mm hardtop. · GT3 adds 84-87 Civic 3dr FWD, hood bulge allowed, no openings. · GT3 Turbo maximum displacement increases from 1800 cc to 1850 cc. · GT taillights may now be original style or a panel graphic with functioning red LED brake lamps; wording change only. · GT3 Nissan SR20VET Limited Prep-Turbocharged OEM engine classified, 1998cc DOHC with Garrett GT2560LS turbo, 2060 lbs. · GT3 Fiat 124 Spider model name corrected from Pininfarina to Pininfarina Spider. · GT3 Fiat 124 Spider Pininfarina reclassified by model year, body style, drivetrain, and wheelbase. · T2 BMW M235iR/M240iR: 240iR/Evo package now permitted without 50 lb penalty; Evo package clarified to 75 lbs. · T2 BMW E92 M3 (08-14) permitted to use Fall Line Suspension arms from G8X/F8x/E9x M3, E9x M3/E82 1M. · GT3 cars can use up to 18" wheels with 12.0" tire cross section and 26.0" diameter at 5% weight penalty, down from 8%. · T2-T4 Touring cars with alternative springs may use performance top hats with spherical bearings on shocks and struts. · T2 BMW E92 M3 (08-14) note reference changed from 77 to 78. · Cadillac CT4-V Blackwing (2022+) classified in T2 at 3800 lbs with 94 x 85.6mm engine. · GT3-TCR: Audi RS3 LMS SEQ power to 90%, weight to 3177 lbs; RS3 LMS DSG power to 90%; Honda Civic Type R power to 90%, weight to 3210 lbs; Hyundai i30N power to 90%, weight to 3254 lbs; VW Golf GTI SEQ power to 90%, weight to 3177 lbs; Gol… · T2-T4 cars model year 2018+ may use non-OEM ECU with 75 lb weight penalty via spec line adjustment. · BMW M2 CS Cup 2020- now permits specific exhaust part #18302459928 and hot country package cooling parts. · 2022+ Cadillac CT4-V Blackwing classified in T2 at 3564cc, 3800 lbs, 18×10/11 wheels, 295 MT tires. · GT3 Ginetta G40 classified with Mazda MZR 1999cc at 2060 lbs or Ford Duratec 2260cc at 2195 lbs. · GT3 Mazda MZR DOHC 1999cc classified with 2195 lbs minimum weight, unrestricted fuel induction. · Volvo S60 2000-2009 classified in GT3. · GT3 2.0L 4V engines now unrestricted at 2195 lbs minimum weight across all makes. · GT3 wing wording corrected: single element airfoil scaled changed to up to maximum chord 10.75 inches. · T2-T4 grill openings may remove non-metallic webbed false sections; 16 square inch limit removed. · T2 Chevrolet Corvette C6 LS2 restrictor increases from 56mm to 58mm. · GT3 adds Fiat Spider 2000, Years 79-81, RWD, 89.76" wheelbase. · GT3 adds Fiat X-19, years 72-89. · T2 BMW Z4M 06-08 weight reduced from 3150 to 3100 lbs. · T2 Dodge Viper SRT-10 loses 50 lbs to 3550; throttle restrictor hole shrinks from 43mm to 41mm. · T2-T4 clarified: grill opening area may increase max 16 sq in for radiator cooling only, retaining factory mesh shape. · T2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted. · T2, T3, T4 clarify that spec lines listing permitted or allowed parts are alternatives to category rules, not replacements. · T2 Spec Mustang model designation changed to Ford Spec Mustang. · GT3 Fun Cup Beetle Sealed weight reduced 210 lbs, to 1850. · GT3-TCR class added: Audi RS3 LMS, Honda Civic Type R, Hyundai i30N, VW Golf GTI at 3100–3200 lbs with 200 tread wear tires. · T2 BMW M2 CS Cup 2020 rear brake rotor reduced from 390 mm to 380 mm. · GT3 Ford Cortina GT 1964-1968 newly classified for competition. · T4 Volkswagen Passat, Jetta 1.8T adds 2014 model year to eligible years. · BMW M2 (2017+) added to T2 with 2979cc engine, 10.5x18 wheels, 295 tires, 3650 lbs weight. · Porsche 911 997.2 GTS (09-12) classified in T2 at 3400 lbs with 60mm flat plate restrictor required. · GT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight. · T2 BMW M2 CS Cup 2020- must run Purple power stick, part #8324089 instead of #TBD. · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two sections and 6010 to 6014X in TA2 Appendix. · T2 Porsche 911/997.1 (06-08) now allows alternate Cargraphics CARP97DFIFKR exhaust manifold. · GT3 now permits current FP spec line cars to compete while maintaining their full FP rule set. · T2 BMW M2 CS Cup 2020- weight increases from 3625 to 3600 lbs; mandatory Purple power stick added. · T3 Honda Civic Type-R 2020+ allows brake rotor 45251-TGH-A01 with 25 lb penalty. · T2 Ford Mustang GT 5.0L 15-17 restrictor grows 55mm to 58mm; 2018- grows 53mm to 55mm. · T2 BMW Z4M 06-08 weight increases from 3100 to 3150 lbs. · T2 BMW E92M3 08-14 weight drops 50 lbs to 3425, intake restrictor reduces 3mm to 77mm. · GT3 Mazda MZR 2.0L fuel induction restrictor increases from 31 to 32 mm. · GT3 Mazda Renesis and 13B Bridgeport choke reduced from 44mm to 42mm. · T2 C5 and C6 Corvettes permit specific dry sump kits and minor air dam trimming up to 3.9 cm depth. · T2 Chevrolet Camaro 1LE auto trans gets new gear ratios and 2.77 final drive ratio. · T2 BMW M3 01-06 minimum competition weight drops 100 lbs to 3000. · T2 Chevrolet Camaro SS/1LE model years expanded from 2010–2014 to 2010–2015. · T2-T4 clutch disc and pressure plate must be at least 95% of factory OEM weight. · Spec Corvette newly classified in T2 at 3375 lbs with 53mm restrictor and 3.75" minimum ride height required. · T2 BMW E92 M3 front and rear springs increased to 1000 lbs/in from 800. · T2 Toyota Supra 2020- spring rates limited to 800# front and 1000# rear maximum. · T2 BMW M2 CS Cup 2020- permitted to remove door glass and mechanism. · T2 BMW M235iR allows 240iR/Evo package with 50 lb penalty, must run DOT tires. · Toyota Supra 2020- newly classified in T2 at 3450 lbs minimum weight with 295 tire and 19-inch wheels. · T2 Honda Civic Type-R gains allowance for PRL cold air intake #PRL PRL-HCR-INT-HVI. · T2 Porsche Carrera S 997.2 (06-08) weight reduced 50 lbs to 3225. · T2 Ford Mustang GT 5.0L (15-17) gear ratios corrected 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. · T2 BMW Z4M 06-08 maximum wheel size increases from 18x9 to 18x10 inches. · T2 BMW M2 CS Cup 2020- and M235iR clarify homologation notes for DOT tires and BMW Motorsports components. · BMW M2 CS Cup 2020+ classified in T2 at 3625 lbs with 2979cc engine, 10.5x18 wheels, 295 tires. · T2 and T3 Nissan 350Z and 370Z permit 44011-RC350 rear caliper kit and SZ350 rotors. · T4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, adds 25 lb penalty. · T3 and T4 FR-S, 86, and BRZ year ranges capped: T3 at 2021, T4 at 2017-2021. · GT3 Mazda MZR and MZR/L5-VE fuel induction sizing changes from 31 to 32. · GT3 Honda Prelude 1992-1997 classified, 2dr FWD, 104 inch wheelbase. · T2 BMW E92 M3 (08-14) weight reduced 50 lbs to 3475, with detailed brake, spring, sway bar, and restrictor specs. · T2 Corvette C5 Z06 restrictor sizes increase to 53mm and 58mm; C6 LS2 to 56mm, LS3 to 50mm; Camaro SS/1LE weight drops 75 lbs to 3625; 2016+ Camaro restrictor to 56mm; Mustang GT 11-14 to 58mm, 15-17 to 55mm, 2018+ to 53mm; Viper SRT-10 th… · T3 Alfa Romeo 4C Launch Edition now allowed in Spec Lines. · T2 Ford Mustang GT 5.0L and Ecoboost 2.3 sway bar part numbers added to notes. · GT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line. · T2 brake rotors expand from ferrous metal only to 2-piece ferrous disks with aluminum hats, within 5% OE diameter. · T2 Corvette C-5 Z06 loses 50 lbs to 3425; Camaro SS/1LE loses 50 lbs to 3650; Mustang GT and Boss 302 gain 275 to 295 tyres. · T2 Porsche Cayman S, Spyder (10-12) allows 800#/in front and 1000#/in rear springs, cooler ducting, rotor ducting, and specific Porsche and StopTech brake items. · T2 Ford Mustang EcoBoost and GT 5.0L gain three optional gear ratio sets for competition use. · GT3 Mazda 12A Peripheral Port added to rule set, 2300 cc, 2292 lbs. · 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. · GT3 4v SIR 4-cylinder engines across multiple brands increase fuel induction from 31 to 32. · GT3 and STU add Borg-Warner EFR6258 to approved turbocharger list. · Cannot read: letter references external document #27663 not provided. · T2 Porsche Cayman S, Spyder (10-12) gains brake, suspension, and drivetrain upgrades: StopTech calipers, 800#/in front and 1000#/in rear springs, Porsche control arms, PDK allowed. · GT3 Nissan KA24E loses permission to use 32mm chokes at 2280 lbs for 2011-2012 only. · 2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine and Eibach PN# 2563.140 springs allowed. · T1 and T2 Corvettes may convert leaf spring suspension to coilover with 800 lb max spring rate allowed. · T2 BMW E92 M3 08-14 gains approved AP Racing brake kit part numbers 13.01.10038 front, 13.01.10053 rear. · T2 Chevrolet Corvette C5 Z06 loses 50 lbs with 45mm restrictor, to 3175; 50 lbs with 55mm restrictor, to 3350. · T3 BMW Z3 M & Coupe 1998-1999 weight reduced from 3350 to 3150 lbs. · T2 Porsche 911 997.2 allows GT3 Cup front fascia with 75 lb penalty; OEM rear deck lid and GT3 Cup splitter now required or prohibited. · T2 Ford Mustang GT 5.0L 15-17 transmission gear ratios corrected to two allowed options. · GT3 Mazda MZR L5-VE gets 31mm SIR restrictor, weight up from 1950 to 2195 lbs, direct injection banned. · T2 Porsche 911/997 (06-08, 09-12, Carrera S 06-08) aero rules relaxed; 997.2 adds 60mm restrictor and PDK +100lbs option. · GT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications. · Pontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18 x 9.5 inches, Sky weight drops to 3200 lbs. · T2 cars now allowed to use ferrous metal 2-piece brake rotors within 5% of OE diameter. · Mazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01. · T2 Nissan 370Z gains alternative Stoptech brake kit option with 50 lb weight penalty. · T2 Ford Mustang Ecoboost 2.3 loses 100 lbs to 3400, wheels widen to 19 x 11, intercooler TIR increases to 50mm. · T2 Mustang GT5.0L gets 19x11 wheels instead of 18x11, Brembro BBK weight penalty removed. · Factory Five Type 65 Coupe R with Ford 302/351 or 5.0/5.2L NA added to GTX-MISC at 2600 lbs. · GT3 Mazda 13B Bridgeport restrictor reduced from 44mm to 42mm. · GT3 Alfa Romeo 4C classified with 1742cc engine, 33mm TIR restrictor, 2325 lbs minimum weight. · GT3 Mazda MZR/L5-VE gets unrestricted induction, drops 245 lbs to 1950, limited to GT2 prep. · GT3 Honda K20C1 turbocharged engine added with 33 mm TIR restrictor, 2350 lbs minimum weight. · GT3 wing end plates change from 11.00 by 4.00 inches rectangle to maximum 64 square inches. · T2 requires onboard fire system; T3 and T4 may have one per GCR 9.3. · T3 Ford Mustang EcoBoost 2015- gains three transmission gear ratio options. · T2 Chevrolet Camaro SS/1LE (10-14) adds Dailey Engineering dry sump P/N 20-02-0666-ASSY and other approved parts. · T2 Camaro SS 1LE gains approval for half shafts Drive Shaft Shop RA-5424 and RA-5425. · T2 Ford Mustang Boss 302 restrictor 54mm to 56mm; GT 5.0L 11-14 restrictor 52mm to 54mm; GT 5.0L 15-17 restrictor 50mm to 52mm; C5 Z06 weight 3525 to 3475 lbs; C6 weight 3450 to 3400 lbs; Porsche 911 997.2 restrictor 60mm to 57mm. · T2 Chevrolet Camaro 1LE 2016- weight reduced from 3600 to 3550 lbs. · T2 Honda Civic Type-R (2017-) weight reduced from 3050 to 3000 lbs; tire TIR requirement increased from 50mm to 51mm. · Mazda RX-8 Base/R3 (04-12) reclassified in T3 and T4 to include Sport and GT variants. · Toyota 86 GT (2017-) added to T3 and T4 Spec Line. · GT3 Nissan adds SR16VE engine, 1596cc, 1690 lbs, unrestricted induction. · GT3 Mazda 12A Bridgeport gains optional 42mm choke at 2010 lbs minimum weight. · T2-T4 spare tire/wheel rules clarified: removable covers can be removed with hardware and bracketry. · T2 Cadillac CTS-V classification expanded from 06-07 to include 04-05 model years. · T2 Cadillac CTS-V 06-07 allowed to use Hotchkiss sway bars up to 36mm front, 25mm rear. · T2 Cadillac CTS-V 06-07 requires 57mm flat plate restrictor. · T2 Ford Mustang GT 5.0L tire size reduced from 315 to 295. · T2 2018+ Audi TT RS gains suspension and intercooler allowances: 30mm front sway bar, 28mm rear, 1200lb/in springs, aftermarket intercooler. · T2 Honda Civic Type-R 2017- weight rises 2900 to 3050 lbs, TIR increases 38mm to 50mm. · 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. · GT3 Mazda 13B and Renesis engines reclassified with new weight specs ranging 2080–2350 lbs. · 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. · T2 Mustang GT anti-roll bars may now be removed or disconnected, previously required as manufactured. · GT3 13B and Renesis rotaries gain 200 lbs minimum weight; 13B Peripheral Port to 2400, Bridge Port to 2400, Renesis Peripheral Port to 2450, Bridge Port to 2450. · GT3 adds Mitsubishi 4G69 SOHC 2378cc engine, 2195 lbs minimum weight, 31mm SIR. · T1-LP Ford Mustang GT 5.0L 2018+ classified at 3400 lbs with 65mm flat plate restrictor. · T2 Audi TT RS (2018-) newly classified at 3400 lbs minimum weight with 19-inch wheels and 275 tire size. · T2 2017 Civic Type R allows any sway bar front/rear up to 30mm, front springs to 800lb, rear to 2000lb. · T4 Mazda MX-5 Club (06-15) and (2016-), T3 MX-5 Cup and Miata (2016-) hardtop rules clarified; wording changes to permitted parts and specifications. · T2, T3, T4 now allow any thermostat serving only OE intent, previously restricted. · T2 Ford Mustang Boss 302 (12-13) weight drops 50 lbs to 3500. · T2 Corvette C6 Coupe/Grand Sport removes 3.0 degrees MAX front camber restriction. · T2 Pontiac Firebird and Chevrolet Camaro SS (98-02) permitted spring relocation to shock. · T3 and T4 Mazda MX-5 Miata eligibility capped at 2018 model year, effective 2019-03-01. · Ford Mustang GT 5.0L 2018+ classified in T2 at 3600 lbs with 50mm restrictor, 19x11 wheels, 315 tyres. · GTX FIA GT3: Audi R8 40mm restrictor 2900 lbs, BMW Z4 70mm 2800 lbs, Ferrari 488 35mm restrictor 3025 lbs classified. · T4 Ford Fiesta ST years corrected to 14-; T4 Fiat 124/Abarth Edition years added 16-18; battery rule clarified. · T2 Porsche Cayman S/GTS model years expanded from 13-14 to 13-15, now includes GTS variant. · T2 Honda Civic Type-R 2017- allows Cuztom Tuning FG-CIV16-V3-TR-BK alternate grill. · T1-T3 spec cars receive clarifications on permitted modifications, documentation requirements, and rule conformance; no performance changes. · T2-T4 subframe bushings may now be replaced with non-spherical bushings of any material.showhide
GT3 Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslowerGT2-ST Acura NSX minimum weight raised to 3000 lbs, restrictor increased to 45mm TIR.
GT3 Mazda MZR Engines #35753aeroneutralGT3 Ford Duratech now allows hood bulge with no openings.
GT3 Disenfranchised GT2 Acura RSX to Run GT3 #35773weightslowerGT3 Acura K20A RSX body disenfranchised from GT2 adds 75 lbs weight penalty.
GT3 Toyota 4Y Engine Request #35885cars addedneutralGT3 Toyota 4Y engine classified at 2030 lbs with unrestricted fuel induction.
GT3 GT3 spec lines clean-up #36008wordingneutralGT3 Toyota model designation changes from DR86 to GR86.
GT3 GT3 Honda spec line clean-up x 2 #36009wordingneutralGT3 Honda spec lines change engine family designation from bore/displacement to K20C1 and K24 model numbers.
GT3 GT3 Mazda spec line clean-up x2 #36010wordingneutralGT3 Mazda spec line numbering changed from 4 to Model, unrestricted to 323, and 2195 to 626.
T2 Allow T4 and T3 RX8 to Disable/Remove Factory Oil Inj. #35761engineunclearT3 and T4 Mazda RX-8 may remove or disable factory oil injection system.
T2 Competition Adjustment Request/Wheel Size of E46 #35895tyres & wheelsfasterT2 BMW M3 01-06 max wheel size increases from 18 x 9 to 18 x 10 inch.
T2 Driveshafts #35916weightslowerT2, T3, T4 driveshafts may use alternative materials or one-piece units; non-OEM adds 25 lbs.
T2 Brake Request for 2009 Porsche Cayman #35723suspension & brakesslowerT2 Porsche Cayman S 06-09 allows StopTech ST60/ST40 brake kit with 50 lb penalty.
GT3 Miata Turbo Clarification #35386weight +100 lbsslowerGT3 Miata Turbo restrictor increases to 35 mm, minimum weight rises to 2350 lbs.
T2 370Z Brake Rotor Size Correction #35487suspension & brakesneutralT2 and T3 Nissan 370Z brake rotors enlarged: front 320x28 to 355x32mm, rear 320x16 to 350x20mm vented.
T2 Letter #35154 2018+ Mustang GT Expansion #35488suspension & brakesneutralT2 Mustang GT 5.0L 2018+ now permits BMR rear upper control arm camber links part #UTCA064.
GT3 Rear Blade Spoiler Clarification #35261aerofasterGT1, GT2, GT3, GTL, GTX rear spoiler maximum surface area limit of 295.0 square inches removed.
GT3 GT Direct Injection allowance and rules #35437enginefasterGT1/GT2/GT3/GTL/GTX Direct Injection now permitted if OE, using only OE pump, hoses, injectors.
GT3 Request to Include Toyota FA24D Engine for use in GT3 #35199cars addedneutralGT3 Toyota FA24D engine classified: 2387cc DOHC, 2195 lbs, 32mm SIR, direct injection permitted.
GT3 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.
GT3 Edit GT3 Nissan QR25DE/DD spec line #35442wordingunclearGT3 Nissan QR25DE/DD spec line edit; text unreadable due to formatting corruption.
T2 2015+ Mustang Sway Bar and A-Arm Request #35154suspension & brakesneutralT2 Mustang GT 5.0L 15-17 now permits BMR rear upper control arm camber links part #UTCA064.
T2 Brake Kits #35245otherneutralT2 Chevrolet Camaro SS, 1LE, Corvette C5/C6, Z06, and Pontiac Firebird, Solstice GXP now allow four or six piston front calipers.
T2 Runoffs wording on Caddy in T2 #35377wordingneutralT2 Cadillac CT4-V Blackwing Runoffs qualification requirement removed.
T2 More Car Lightening Stuff #35319weightfasterT2, T3, T4 battery replacement wording simplified; OEM weight tolerance requirement removed.
T2 Inclusion of B-C spec cars in T4 #35374cars addedneutralT4 now permits C-Spec cars to compete alongside B-Spec cars.
T2 T2-T4 Set expiration dates on spec lines #35378wordingneutralT2-T4 spec lines for 46 cars expire 12/31/24; appeal required to continue.
T2 Reply to letter #35161 and #31661 #35384weight +75 lbsslowerT2 Chevrolet Camaro 1LE minimum weight increases to 3575 lbs, restrictor plate widens to 60mm.
GT3 Turbo Help #35042weight -100 lbsfasterGT3 Mazda BP4W turbocharged OEM engine weight reduced from 2060 to 1960 lbs.
GT3 Competition Adjustment Request for 13B Peripheral Port #35100weight -100 lbsfasterGT3 Mazda 13B peripheral port weight reduced to 2100 lbs.
GT3 Request to Include Toyota GR 86 in GT3 #35197cars addedneutralGT3 adds Toyota GR 86 (DR86) 2021–2024, 2-door RWD, 101.3 in wheelbase.
GT3 Fastrack Toyota 3S Correction #35258engineunclearGT3 Toyota 3S bore increases to 86.0mm, stroke decreases to 86.0mm.
T2 Rebalance Blackwing Cadillac T2 #35079tyres & wheelsfasterT2 Cadillac CT4-V Blackwing rear wheels widen from 18 x 10 to 18 x 11.
T2 M2 CS RACING #35130weight -50 lbsfasterT2 BMW M2 CS Cup drops 50 lbs to 3550; M235iR drops 50 lbs to 3300.
T2 Spec Corvette in T2 #35139weight -175 lbsfasterT2 Spec Corvette minimum weight drops 175 lbs to 3200, tire rules tighten to Nankang NS-2R only.
T2 T2 Viper BoP #35155tyres & wheelsslowerT2 Dodge Viper SRT-10 rear tyre narrowed from 345/30 to 335/30.
T2 BOP Adjustment for 5.0L Mustangs #35156weight +75 lbsslowerT2 Ford Mustang GT 5.0L three generations gain 50-75 lbs minimum weight; restrictors increase to 58-60mm.
T2 Take at Look at T-2 BOP #35161weight -50 lbsfasterT2 Chevrolet Camaro 1LE minimum weight drops 50 lbs to 3500, restrictor opens to 58mm flat plate.
T2 C5 Corvette Spec Line Oversight #35169inductionfasterT2 C5 Z06 removes restrictor note from weight; C5/C6 Corvettes increase restrictors to 59mm, 63mm LS2, 53mm LS3.
T2 Requested Update of Model Years of 370Z #35231wordingneutralT3 Nissan 370Z model years expanded to include NISMO Edition through 2022.
GT3 Toyota Engine Classification Request #35019engineneutralGT3 Toyota 3S DOHC engine classified at 1998 cc, 1960 lbs minimum weight, unrestricted fuel induction.
GT3 GT3 2.0L SIR & weight #35171inductionslowerGT3 2.0L SIR cars lose 32mm unrestricted option, now require restrictor at 2195lbs minimum.
GT3 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.
T2 M2 CS RACING #35122aeroneutralT2 BMW M2 CS Cup 2020- permitted to add hood vents conforming to 9.1.9.2.D.8.a.7.
GT3 GT3 TCR 200 TW tires #34993tyres & wheelsslowerGT3-TCR Audi RS3 LMS, Honda Civic Type R, Hyundai i30 N, VW Golf GTi must use 200 tread wear tires only.
GT3 Classify Honda B20 engine in GT3 CRX #34781cars addedneutralGT3 Honda B20 engine newly classified for use in CRX, 1973cc displacement, aluminum head, DOHC.
GT3 Addendum to letter 33913, GT3 DOT tires. #34627tyres & wheelsfasterGT3 cars using 15" American Racer 23.5-10.0-15 bias ply tires avoid weight penalty.
T2 Corvette LS2 Restrictor Plate Adjustment #34456inductionfasterT2 Chevrolet Corvette C6 LS2 restrictor plate increases from 58mm to 60mm flat plate.
T2 Blacking Cadillac Fuel Capacity #34624wordingneutralT2 Cadillac CT4-V Blackwing permitted to use Radium fuel surge tank behind fireproof bulkhead.
T2 Rules Clarification for Mazda RX8 Spec Line #34395wordingneutralT3 Mazda RX-8 removes transmission/final drive pairing requirement; T4 removes same requirement, adds Mazdaspeed radiator and coil spring kit.
T2 rule book corrections #34437otherfasterT3 BMW 320i (14-15) gains aftermarket intercooler permission; T4 loses it.
T2 Ride Height Correction for the T3 Solstice. #34615wordingneutralT3 Pontiac Solstice GXP minimum ride height set to 3 inches.
T2 370Z Obsolete Parts & NISMO Alternatives to SPL Parts #34297wordingneutralT2 Nissan 370Z allows NISMO suspension alternatives to SPL parts; rear toe arms removed from permitted list.
T2 2009 Porsche Cayman Classing Request #34147wordingneutralT2 Porsche Cayman S model year range extended from 06-08 to 06-09.
GT3 Please classify Fields Cardinal V8 #33784cars addedneutralFields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight.
T2 C5 Z06 Straight Line Speed #33575inductionslowerT2 Chevrolet Corvette C5 Z06 restrictor increases from 53mm to 56mm; 58mm option removed.
T2 Allowance of any nonmetallic bushing material in T2 #33833suspension & brakesneutralT2 upper and lower control arm bushings can now use polyurethane, delrin, or alternate synthetic materials.
T2 Allow Adjustable stabilizer bar links #33861suspension & brakesneutralT2 Cadillac CT4-V Blackwing now permits adjustable sway bar end links.
T2 Honda Civic Type R Tire Size Increase #33672tyres & wheelsfasterT2 Honda Civic Type-R tire size increases from 275 to 295.
T2 Mustang OEM Grill Request #33333aeroneutralT2/T3 Mustang GT 5.0L and V6 (11-14) may remove upper grille fog lights, replace with mesh or screen.
GT3 Remove Nissan VG30 engine from GT3 #33609removedneutralGT3 Nissan VG30 engine removed from class entirely.
GT3 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.
GT3 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.
T2 BMW M235iR/M240iR Aftermarket 2WNR Shocks Allowed - Touring 2 #33464weight -50 lbsfasterT2 BMW M235iR weight reduced 50 lbs to 3350, aftermarket shocks now allowed.
T2 Touring (T2-T5) Category #33617cars addedneutralT5 class added as regional-only; T5 tyres maximum width 225, minimum aspect ratio 45.
T2 ENO 9.1.9.2.D.1.e.1.a. #33651suspension & brakesneutralT2-T5 Touring front and rear suspension maximum negative camber changed to 3.5 degrees.
GT3 Turbocharged Engine Rules #33145cars addedneutralGT3 Mazda BP4W Turbocharged OEM engine added at 2060 lbs with 34mm TIR and IHI RHF5 VJ35 turbocharger.
GT3 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.
GT3 GT3 Nissian SR20VET unrestricted ECU change #33432enginefasterGT3 Nissan SR20VET turbo changes to GT2860RS and allows open ECU instead of OEM stock.
T2 Heavy Cars #33345weight +125 lbsslowerT2 Dodge Viper SRT-10 wheel size 18x11 rear, weight to 3675 lbs, throttle restrictor hole 44mm convertible or 42mm hardtop.
GT3 GT3 Turbo Displacement Clarification #32952enginefasterGT3 Turbo maximum displacement increases from 1800 cc to 1850 cc.
GT3 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.
GT3 Correct Model GT3 - Fiat #32776wordingneutralGT3 Fiat 124 Spider model name corrected from Pininfarina to Pininfarina Spider.
GT3 Correct Fiat Spider Years #32149wordingneutralGT3 Fiat 124 Spider Pininfarina reclassified by model year, body style, drivetrain, and wheelbase.
T2 BMW M235iR/M240iR Min Weight Clarification #32430wordingfasterT2 BMW M235iR/M240iR: 240iR/Evo package now permitted without 50 lb penalty; Evo package clarified to 75 lbs.
T2 Follow up to Letter 30888 #32477suspension & brakesfasterT2 BMW E92 M3 (08-14) permitted to use Fall Line Suspension arms from G8X/F8x/E9x M3, E9x M3/E82 1M.
GT3 wheel size addition #32247tyres & wheelsfasterGT3 cars can use up to 18" wheels with 12.0" tire cross section and 26.0" diameter at 5% weight penalty, down from 8%.
T2 Request Alternate Front & Rear Strut/Shock Top Hats #32452suspension & brakesneutralT2-T4 Touring cars with alternative springs may use performance top hats with spherical bearings on shocks and struts.
T2 Request BoP E92 torque #32456wordingneutralT2 BMW E92 M3 (08-14) note reference changed from 77 to 78.
T2 Classify Cadillac Blackwing #32535cars addedneutralCadillac CT4-V Blackwing (2022+) classified in T2 at 3800 lbs with 94 x 85.6mm engine.
GT3 GT3 TCR Car Feedback #31677engine +2 lbsslowerGT3-TCR: Audi RS3 LMS SEQ power to 90%, weight to 3177 lbs; RS3 LMS DSG power to 90%; Honda Civic Type R power to 90%, weight to 3210 lbs; Hyundai i30N power to 90%, weight to 3254 lbs; VW Golf GTI SEQ power to 90%, weight to 3177 lbs; Gol…
T2 Request to Allow the Use of Aftermarket ECU's in Touring #31067weightslowerT2-T4 cars model year 2018+ may use non-OEM ECU with 75 lb weight penalty via spec line adjustment.
T2 BMW M2 CS Cup 2020- Exhaust #32243wordingunclearBMW M2 CS Cup 2020- now permits specific exhaust part #18302459928 and hot country package cooling parts.
GT3 Request to Classify Ginetta G40 in GT3 #31598cars addedneutralGT3 Ginetta G40 classified with Mazda MZR 1999cc at 2060 lbs or Ford Duratec 2260cc at 2195 lbs.
GT3 Volvo S60 in GT3 #31970cars addedneutralVolvo S60 2000-2009 classified in GT3.
GT3 GT3 2.0L 4V engines now unrestricted. #32190enginefasterGT3 2.0L 4V engines now unrestricted at 2195 lbs minimum weight across all makes.
GT3 TB correction to wing wording #32191wordingneutralGT3 wing wording corrected: single element airfoil scaled changed to up to maximum chord 10.75 inches.
T2 Reply to letter #31486/29879 T2-T4 Grill openings #31935aerofasterT2-T4 grill openings may remove non-metallic webbed false sections; 16 square inch limit removed.
T2 C6 Restrictor Help #31995inductionfasterT2 Chevrolet Corvette C6 LS2 restrictor increases from 56mm to 58mm.
GT3 Request to add Fiat to GT3 CARS #31803cars addedneutralGT3 adds Fiat Spider 2000, Years 79-81, RWD, 89.76" wheelbase.
GT3 Request to add Fiat to GT3 CARS #31804cars addedneutralGT3 adds Fiat X-19, years 72-89.
T2 BMW Z4M Adjustment #31885weight -50 lbsfasterT2 BMW Z4M 06-08 weight reduced from 3150 to 3100 lbs.
T2 Touring 2 BOP adjustments for 2022 #31480weight -50 lbsfasterT2 Dodge Viper SRT-10 loses 50 lbs to 3550; throttle restrictor hole shrinks from 43mm to 41mm.
T2 Reply to letter 29879 T2-T4 Grill Openings #31486aerofasterT2-T4 clarified: grill opening area may increase max 16 sq in for radiator cooling only, retaining factory mesh shape.
T2 Request to clarify radiator hoses #31682wordingneutralT2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted.
T2 Clarify Permitted/Allowed #31743wordingneutralT2, T3, T4 clarify that spec lines listing permitted or allowed parts are alternatives to category rules, not replacements.
T2 SMG #31837wordingneutralT2 Spec Mustang model designation changed to Ford Spec Mustang.
GT3 31032 correction to weight #31525weight -210 lbsfasterGT3 Fun Cup Beetle Sealed weight reduced 210 lbs, to 1850.
GT3 Add TCR cars to GT3 #31540cars addedneutralGT3-TCR class added: Audi RS3 LMS, Honda Civic Type R, Hyundai i30N, VW Golf GTI at 3100–3200 lbs with 200 tread wear tires.
T2 Typo for BMW M2 CS Cup 2020 #31173suspension & brakesslowerT2 BMW M2 CS Cup 2020 rear brake rotor reduced from 390 mm to 380 mm.
GT3 Please approve 1964-1968 Ford Cortina GT for competition in GT# #30941cars addedneutralGT3 Ford Cortina GT 1964-1968 newly classified for competition.
T2 Request to Classify 2014 VW Jetta 1.8t TSI #30436cars addedneutralT4 Volkswagen Passat, Jetta 1.8T adds 2014 model year to eligible years.
T2 Request new car 2017 BMW M2 #30486cars addedneutralBMW M2 (2017+) added to T2 with 2979cc engine, 10.5x18 wheels, 295 tires, 3650 lbs weight.
T2 Request to Classify Porsche 997.2 GTS in T2 (body not = to C2S) #30686cars addedneutralPorsche 911 997.2 GTS (09-12) classified in T2 at 3400 lbs with 60mm flat plate restrictor required.
GT3 Request car classification #31032cars addedneutralGT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight.
T2 BMW M2 CS Power Stick Part Number #31087wordingneutralT2 BMW M2 CS Cup 2020- must run Purple power stick, part #8324089 instead of #TBD.
GT3 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.
T2 997.1 EO #30933wordingneutralT2 Porsche 911/997.1 (06-08) now allows alternate Cargraphics CARP97DFIFKR exhaust manifold.
GT3 Request to Permit FP cars in GT3 #30611cars addedneutralGT3 now permits current FP spec line cars to compete while maintaining their full FP rule set.
T2 Request #30406weightfasterT2 BMW M2 CS Cup 2020- weight increases from 3625 to 3600 lbs; mandatory Purple power stick added.
T2 Civic Type R Brake Rotors #29817weightslowerT3 Honda Civic Type-R 2020+ allows brake rotor 45251-TGH-A01 with 25 lb penalty.
T2 Mustang S550 Parity in T2 #29925inductionfasterT2 Ford Mustang GT 5.0L 15-17 restrictor grows 55mm to 58mm; 2018- grows 53mm to 55mm.
T2 Request BOP on BMW Z4 T2 car #30597weight +50 lbsslowerT2 BMW Z4M 06-08 weight increases from 3100 to 3150 lbs.
T2 E92 #30639weight -50 lbsfasterT2 BMW E92M3 08-14 weight drops 50 lbs to 3425, intake restrictor reduces 3mm to 77mm.
GT3 Mazda MZR 2.0L Engine #30455inductionfasterGT3 Mazda MZR 2.0L fuel induction restrictor increases from 31 to 32 mm.
GT3 Disfranchised GT3 Mazda, correct choke size #30570inductionslowerGT3 Mazda Renesis and 13B Bridgeport choke reduced from 44mm to 42mm.
T2 C5/6 Corvette in T1, T1-LP and T2 Dry Sump Standardization #29046wordingneutralT2 C5 and C6 Corvettes permit specific dry sump kits and minor air dam trimming up to 3.9 cm depth.
T2 Request for Chevrolet Camaro 1LE (2016-) Auto Trans #29067wordingunclearT2 Chevrolet Camaro 1LE auto trans gets new gear ratios and 2.77 final drive ratio.
T2 Request to add 2015 to Chevrolet Camaro SS/1LE 2010-2014 #29736cars addedneutralT2 Chevrolet Camaro SS/1LE model years expanded from 2010–2014 to 2010–2015.
T2 Request consistency review in GCR #30263wordingslowerT2-T4 clutch disc and pressure plate must be at least 95% of factory OEM weight.
T2 Class Spec Corvette in T2? #30297cars addedneutralSpec Corvette newly classified in T2 at 3375 lbs with 53mm restrictor and 3.75" minimum ride height required.
T2 E92 BMW Spring Rate Request #30391suspension & brakesfasterT2 BMW E92 M3 front and rear springs increased to 1000 lbs/in from 800.
T2 Please correct recent T2 Spec Line #30401suspension & brakesneutralT2 Toyota Supra 2020- spring rates limited to 800# front and 1000# rear maximum.
T2 Request BMW M2CS door glass removal #30254aerofasterT2 BMW M2 CS Cup 2020- permitted to remove door glass and mechanism.
T2 Request Addition of BMW M240iR #29503cars addedslowerT2 BMW M235iR allows 240iR/Evo package with 50 lb penalty, must run DOT tires.
T2 2021 Toyota Supra #29567cars addedneutralToyota Supra 2020- newly classified in T2 at 3450 lbs minimum weight with 295 tire and 19-inch wheels.
T2 Request Cold Air Intake for Honda Civic Type R #29942wordingneutralT2 Honda Civic Type-R gains allowance for PRL cold air intake #PRL PRL-HCR-INT-HVI.
T2 Adjust T2 spec line that was missed in T2 BOP #30055weight -50 lbsfasterT2 Porsche Carrera S 997.2 (06-08) weight reduced 50 lbs to 3225.
T2 Fix T2 Mustang spec line #30106wordingneutralT2 Ford Mustang GT 5.0L (15-17) gear ratios corrected 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.
T2 Z4 Wheel Size #30113tyres & wheelsfasterT2 BMW Z4M 06-08 maximum wheel size increases from 18x9 to 18x10 inches.
T2 Clarify T2 Spec lines #30194wordingneutralT2 BMW M2 CS Cup 2020- and M235iR clarify homologation notes for DOT tires and BMW Motorsports components.
T2 Request to Classify BMW M2 CS #29523cars addedneutralBMW M2 CS Cup 2020+ classified in T2 at 3625 lbs with 2979cc engine, 10.5x18 wheels, 295 tires.
T2 350Z Rear Caliper Replacement #29710wordingneutralT2 and T3 Nissan 350Z and 370Z permit 44011-RC350 rear caliper kit and SZ350 rotors.
T2 Request Mustang 8.8†rear axle replacement #29860weightslowerT4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, adds 25 lb penalty.
T2 Cap year range on all 86s #29908wordingneutralT3 and T4 FR-S, 86, and BRZ year ranges capped: T3 at 2021, T4 at 2017-2021.
GT3 Mazda MZR SIR Sizing #29555inductionfasterGT3 Mazda MZR and MZR/L5-VE fuel induction sizing changes from 31 to 32.
GT3 Request to Classify 1992-1997 Honda Prelude #29687cars addedneutralGT3 Honda Prelude 1992-1997 classified, 2dr FWD, 104 inch wheelbase.
T2 Request to Reevaluate T2 Spec Line for E92 M3 #28266weight -50 lbsfasterT2 BMW E92 M3 (08-14) weight reduced 50 lbs to 3475, with detailed brake, spring, sway bar, and restrictor specs.
T2 Request for Parity Among Vehicles Including S550 Mustang #29486induction -75 lbsfasterT2 Corvette C5 Z06 restrictor sizes increase to 53mm and 58mm; C6 LS2 to 56mm, LS3 to 50mm; Camaro SS/1LE weight drops 75 lbs to 3625; 2016+ Camaro restrictor to 56mm; Mustang GT 11-14 to 58mm, 15-17 to 55mm, 2018+ to 53mm; Viper SRT-10 th…
T2 Alfa Romeo 4C Launch Edition #29531wordingneutralT3 Alfa Romeo 4C Launch Edition now allowed in Spec Lines.
T2 Request 2018+ mustang swaybar update #28659wordingneutralT2 Ford Mustang GT 5.0L and Ecoboost 2.3 sway bar part numbers added to notes.
GT3 GT Category Wording #29193wordingunclearGT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line.
T2 Request to Clarify New 2-piece Brake Rotor Rule #29106wordingneutralT2 brake rotors expand from ferrous metal only to 2-piece ferrous disks with aluminum hats, within 5% OE diameter.
T2 please consider BoP for the following cars in T2 #29266weight -50 lbsfasterT2 Corvette C-5 Z06 loses 50 lbs to 3425; Camaro SS/1LE loses 50 lbs to 3650; Mustang GT and Boss 302 gain 275 to 295 tyres.
T2 Request clarification on most recent approval by the Board #29284wordingneutralT2 Porsche Cayman S, Spyder (10-12) allows 800#/in front and 1000#/in rear springs, cooler ducting, rotor ducting, and specific Porsche and StopTech brake items.
T2 Request to correct GCR for 2018+ FORD Mustang GT & Ecoboost #28803wordingneutralT2 Ford Mustang EcoBoost and GT 5.0L gain three optional gear ratio sets for competition use.
GT3 Request to add Mazda 12A Peripheral Port to GT3 rule set #28842cars addedneutralGT3 Mazda 12A Peripheral Port added to rule set, 2300 cc, 2292 lbs.
GT3 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.
GT3 STO Gurney flap wicker clarification #28883wordingneutralSTO rear wing wording clarified: 'wicker' changed to 'Gurney flap' in maximum chord and mounting height rules.
GT3 GT3 4v SIR size increase. #28931inductionfasterGT3 4v SIR 4-cylinder engines across multiple brands increase fuel induction from 31 to 32.
GT3 Request for Addition to GT3 Approved Turbo List #27576wordingneutralGT3 and STU add Borg-Warner EFR6258 to approved turbocharger list.
T2 Request to Add a Vehicle to the Roster (contd.) #27698cars addedunclearCannot read: letter references external document #27663 not provided.
T2 Request brake upgrade and electric power steering pump #28946suspension & brakesfasterT2 Porsche Cayman S, Spyder (10-12) gains brake, suspension, and drivetrain upgrades: StopTech calipers, 800#/in front and 1000#/in rear springs, Porsche control arms, PDK allowed.
GT3 Request Nissan KA24E specifications #28808inductionslowerGT3 Nissan KA24E loses permission to use 32mm chokes at 2280 lbs for 2011-2012 only.
T2 Request to Classify 2004 Mercedes Benz 320 CLK #27663cars addedneutral2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine and Eibach PN# 2563.140 springs allowed.
T2 Consider coil spring conversion Corvette in T2 #28824suspension & brakesneutralT1 and T2 Corvettes may convert leaf spring suspension to coilover with 800 lb max spring rate allowed.
T2 Please Add the Following BBK to Allowed List for E92 M3 #28421suspension & brakesneutralT2 BMW E92 M3 08-14 gains approved AP Racing brake kit part numbers 13.01.10038 front, 13.01.10053 rear.
T2 C5 Weight Adjustment #28433weight -50 lbsfasterT2 Chevrolet Corvette C5 Z06 loses 50 lbs with 45mm restrictor, to 3175; 50 lbs with 55mm restrictor, to 3350.
T2 Z3M Roadster Weight #28437weightfasterT3 BMW Z3 M & Coupe 1998-1999 weight reduced from 3350 to 3150 lbs.
T2 Limit Changes to the 997.2 Porsche #28242aeroslowerT2 Porsche 911 997.2 allows GT3 Cup front fascia with 75 lb penalty; OEM rear deck lid and GT3 Cup splitter now required or prohibited.
T2 Correct T2 Mustang Transmission #28732wordingunclearT2 Ford Mustang GT 5.0L 15-17 transmission gear ratios corrected to two allowed options.
GT3 Error Regarding Mazda Engine Listing #28119induction +245 lbsslowerGT3 Mazda MZR L5-VE gets 31mm SIR restrictor, weight up from 1950 to 2195 lbs, direct injection banned.
T2 Request to Readjust the T2 Porsches #27746aeroslowerT2 Porsche 911/997 (06-08, 09-12, Carrera S 06-08) aero rules relaxed; 997.2 adds 60mm restrictor and PDK +100lbs option.
GT3 Windshield Clips #27323wordingneutralGT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications.
T2 Please Switch the Solstice GXP as Specified in T2, to T3 #27413cars added -50 lbsfasterPontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18 x 9.5 inches, Sky weight drops to 3200 lbs.
T2 Request for Two Piece Stop Tech Brake Rotors #27582otherneutralT2 cars now allowed to use ferrous metal 2-piece brake rotors within 5% of OE diameter.
T2 Request to Classify all Mazda RX8 Models in T3/T4 #27606cars addedneutralMazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01.
T2 Request for Alternative Brake Kit on Nissan 370Z #27912suspension & brakesslowerT2 Nissan 370Z gains alternative Stoptech brake kit option with 50 lb weight penalty.
T2 2015- Current Ecoboost Mustang #27971weight -100 lbsfasterT2 Ford Mustang Ecoboost 2.3 loses 100 lbs to 3400, wheels widen to 19 x 11, intercooler TIR increases to 50mm.
GT3 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.
GT3 Request restrictor size change request #26958inductionslowerGT3 Mazda 13B Bridgeport restrictor reduced from 44mm to 42mm.
GT3 Request to Classify Alfa Romeo 4C #27322cars addedneutralGT3 Alfa Romeo 4C classified with 1742cc engine, 33mm TIR restrictor, 2325 lbs minimum weight.
GT3 Request for Mazda 2.5l MZR/L5-VE #27570induction -245 lbsfasterGT3 Mazda MZR/L5-VE gets unrestricted induction, drops 245 lbs to 1950, limited to GT2 prep.
GT3 GT3 turbo engines add Honda #28033cars addedneutralGT3 Honda K20C1 turbocharged engine added with 33 mm TIR restrictor, 2350 lbs minimum weight.
GT3 GT3 wing end plate #28035aerounclearGT3 wing end plates change from 11.00 by 4.00 inches rectangle to maximum 64 square inches.
T2 Clarification of On-Board Fire System for T2 #27183wordingneutralT2 requires onboard fire system; T3 and T4 may have one per GCR 9.3.
T2 Mustang Ecoboost and GT Transmission #27439otherunclearT3 Ford Mustang EcoBoost 2015- gains three transmission gear ratio options.
T2 Request for Dailey Engineering Dry Sump on 2010 Camaro SS #27514otherneutralT2 Chevrolet Camaro SS/1LE (10-14) adds Dailey Engineering dry sump P/N 20-02-0666-ASSY and other approved parts.
T2 Request for Half Shafts - 2014 Camaro SS 1LE #27584otherneutralT2 Camaro SS 1LE gains approval for half shafts Drive Shaft Shop RA-5424 and RA-5425.
T2 Request for Parity Among Vehicles #27665induction -50 lbsfasterT2 Ford Mustang Boss 302 restrictor 54mm to 56mm; GT 5.0L 11-14 restrictor 52mm to 54mm; GT 5.0L 15-17 restrictor 50mm to 52mm; C5 Z06 weight 3525 to 3475 lbs; C6 weight 3450 to 3400 lbs; Porsche 911 997.2 restrictor 60mm to 57mm.
T2 Request for 2016-2020 Camaro SS Help #27776weight -50 lbsfasterT2 Chevrolet Camaro 1LE 2016- weight reduced from 3600 to 3550 lbs.
T2 Request for Competitive Adjustments to Honda Civic Type R #27839weight -50 lbsfasterT2 Honda Civic Type-R (2017-) weight reduced from 3050 to 3000 lbs; tire TIR requirement increased from 50mm to 51mm.
T2 T4 RX8 Classification Error #27902wordingneutralMazda RX-8 Base/R3 (04-12) reclassified in T3 and T4 to include Sport and GT variants.
T2 Request to add Toyota 86 GT to Spec Line #27910cars addedneutralToyota 86 GT (2017-) added to T3 and T4 Spec Line.
GT3 Request to Add SR16VE to GT-3 Spec Lines #27357cars addedneutralGT3 Nissan adds SR16VE engine, 1596cc, 1690 lbs, unrestricted induction.
GT3 Requesting Increase in Choke Diameter for Mazda 12A Bridgeport #27043inductionfasterGT3 Mazda 12A Bridgeport gains optional 42mm choke at 2010 lbs minimum weight.
T2 Request spare tire/wheel clarification #27012wordingneutralT2-T4 spare tire/wheel rules clarified: removable covers can be removed with hardware and bracketry.
T2 Request to change Cadillac CTS-V years from 06-07 to 04-07 #26842cars addedneutralT2 Cadillac CTS-V classification expanded from 06-07 to include 04-05 model years.
T2 Request to allow Hotchkiss front / rear sway bars on T2 CTS-V #26845suspension & brakesfasterT2 Cadillac CTS-V 06-07 allowed to use Hotchkiss sway bars up to 36mm front, 25mm rear.
T2 Correct T2 Mustang tire size #27024tyres & wheelsslowerT2 Ford Mustang GT 5.0L tire size reduced from 315 to 295.
T2 2018+ Audi TT RS Suspension Allowances #26631suspension & brakesfasterT2 2018+ Audi TT RS gains suspension and intercooler allowances: 30mm front sway bar, 28mm rear, 1200lb/in springs, aftermarket intercooler.
T2 Request BOP adjustment for 2018 Honda Civic Type R-TIR removal #26882weight +150 lbsslowerT2 Honda Civic Type-R 2017- weight rises 2900 to 3050 lbs, TIR increases 38mm to 50mm.
GT3 Request GTX Fuel injection for previous GT-1 tube frame cars #26141inductionfasterGTX tube frame cars gain fuel injection with 90mm maximum throttle body size.
GT3 Request to Classify Ligier JS2 R #26535cars addedneutralLigier JS2 R classified in GTX, no performance parameters specified in filing.
GT3 26076 revised Spec line chart #26528engineunclearGT3 Mazda 13B and Renesis engines reclassified with new weight specs ranging 2080–2350 lbs.
GT3 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.
T2 Request for Removal of Rear Anti-roll Bar in T2 Mustang GT #26533suspension & brakesfasterT2 Mustang GT anti-roll bars may now be removed or disconnected, previously required as manufactured.
GT3 Request clarification on bridge porting for rotary #26076weightslowerGT3 13B and Renesis rotaries gain 200 lbs minimum weight; 13B Peripheral Port to 2400, Bridge Port to 2400, Renesis Peripheral Port to 2450, Bridge Port to 2450.
T2 Request Mustang GT Limited Prep 2018 Classification #24431cars addedneutralT1-LP Ford Mustang GT 5.0L 2018+ classified at 3400 lbs with 65mm flat plate restrictor.
T2 Request to Classify 2018 Audi TT RS #25961cars addedneutralT2 Audi TT RS (2018-) newly classified at 3400 lbs minimum weight with 19-inch wheels and 275 tire size.
T2 Request for Adjustments on 2017+ Civic Type R #25969suspension & brakesneutralT2 2017 Civic Type R allows any sway bar front/rear up to 30mm, front springs to 800lb, rear to 2000lb.
T2 Correct Mazda MX-5 Hard Top Notes #26137wordingneutralT4 Mazda MX-5 Club (06-15) and (2016-), T3 MX-5 Cup and Miata (2016-) hardtop rules clarified; wording changes to permitted parts and specifications.
T2 Consider opening class rules to allow any thermostat #26187wordingneutralT2, T3, T4 now allow any thermostat serving only OE intent, previously restricted.
T2 Ford Mustang Boss 302 (12-13) - correct weight #26287weight -50 lbsfasterT2 Ford Mustang Boss 302 (12-13) weight drops 50 lbs to 3500.
T2 Request camber correction 005-2013 corvette C6 #26288suspension & brakesfasterT2 Corvette C6 Coupe/Grand Sport removes 3.0 degrees MAX front camber restriction.
T2 Request 98-02 Firebird 98-02 Camaro reloacte rear spring #26291suspension & brakesneutralT2 Pontiac Firebird and Chevrolet Camaro SS (98-02) permitted spring relocation to shock.
T2 Cap 2016 Mazda Miata year at 2018 #26388wordingneutralT3 and T4 Mazda MX-5 Miata eligibility capped at 2018 model year, effective 2019-03-01.
T2 Class Ford Mustang GT 2018+ (reference letter 24431) #26400cars addedneutralFord Mustang GT 5.0L 2018+ classified in T2 at 3600 lbs with 50mm restrictor, 19x11 wheels, 315 tyres.
GT3 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.
T2 Errors, Omissions, and Updates (Various) #22414wordingneutralT4 Ford Fiesta ST years corrected to 14-; T4 Fiat 124/Abarth Edition years added 16-18; battery rule clarified.
T2 Request to classify 2015 Cayman GTS 3.4L in T2 #25335cars addedneutralT2 Porsche Cayman S/GTS model years expanded from 13-14 to 13-15, now includes GTS variant.
T2 Request for 2017-2018 Honda Civic Type R - 4 BOP Grill #25513wordingneutralT2 Honda Civic Type-R 2017- allows Cuztom Tuning FG-CIV16-V3-TR-BK alternate grill.
T2 Add Clarification to Spec Car Classifications Vehicle Spec #25774wordingneutralT1-T3 spec cars receive clarifications on permitted modifications, documentation requirements, and rule conformance; no performance changes.
T2 Clarify Subframe Bushings Permitted for T2-T4 #25800wordingneutralT2-T4 subframe bushings may now be replaced with non-spherical bushings of any material.
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 T2" is the class's best as a share of T2'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 T2'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.