Quickest here:STL 1:54.845 Gavin Wardle, Cal Club 2026 race · T3 1:55.675 Scotty B White, Cal Club 2026 race · T2 1:51.198 Rylan Hazelton, Cal Club 2026 qualifying
STLT3T2solid race · dashed qualifying · slower is lower
STLT3T2solid race · dashed qualifying · each class's best lap as a share of STL's at the same event (the reference class, changeable above); 100% is level, higher is quicker
Event
STL
T3
T2
Qual best
Race best
Trap
Qual best
Race best
Trap
vs STL
% of STL
Qual best
Race best
Trap
vs STL
% of STL
Cal Club 2026 CALCL262026-02-21
1:57.526Jared Korth · fastest of 10 · top 5 within 1.2s+2.563s (+2.23%)
1:54.845Gavin Wardle · fastest of 11 · top 5 within 4.7s-0.837s (-0.72%)
136.6Bryce Johnson+26.2 mph (+23.7%)
1:55.970Scotty B White · fastest of 4 · top 4 within 10.5s+0.005s (+0.00%)
1:55.675Scotty B White · fastest of 5 · top 5 within 12.1s-0.522s (-0.45%)
137.2Scotty B White+25.7 mph (+23.1%)
+0.830squal -1.556s
100.7%qual 98.7%
1:51.198Rylan Hazelton · fastest of 10 · top 5 within 2.5s-2.867s (-2.51%)
1:51.454Rylan Hazelton · fastest of 10 · top 5 within 3.0s-1.304s (-1.16%)
146.6Patrick Howe+32.2 mph (+28.1%)
-3.391squal -6.328s
97.0%qual 94.6%
48 rule changes (STL: 3, T3: 18, T2: 27)11 weight · 6 suspension & brakes · 4 cars added · 4 tyres & wheels · 3 engine · 3 induction · 1 aero · 15 wording · 1 other · 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. · T3 Ford Mustang V6 Spec Line expands to include 2005-2010 chassis and body with 2011-2014 engine. · T3 Nissan 350Z DE Motor loses 25 lbs to 3100, HR Motor loses 25 lbs to 3250. · T2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously prohibited except in specified examples. · STL minimum weights increase across all classes, 1300 cc gains 195 lbs to 1950, up to 1850 cc at 2500. · 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. · T3 Ford Spec Mustang restrictor opens to 45mm, weight drops to 3400 lbs. · T3 BMW Spec E9X tire width increases to 255 from 225; spec E9X tire or any DOT permitted. · T3 SpecE46 permitted tire width increases from 225 to 245. · T2, T3, T4 cars may relocate under-dash electronics and fuse boxes for access after roll cage installation. · 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 Ford Mustang EcoBoost loses optional 2-piece 355mm Brembo rotor brake kit option with 50 lb penalty. · 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. · T3 Honda S2000 wheels grow to 17x9.0 front and 17x10 rear; tyres widen to 255 front and 275 rear. · 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. · STL/STU Lotus weight reduced: Evora GT4 to 2700 lbs, Elise Cup R to 2250 lbs, Elise/Exige SC to 2450-2550 lbs. · 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. · T2, T3, T4 Spec Lines table header changed from T2 to ET. · BMW Spec E46 in T3 updates to SpecE46 rules Version 3.0. · STL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1 instead of 2500 lbs; spec components removed, only alternative tires allowed. · 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. · T3 Ford Mustang V6 15-17 weight drops 50 lbs to 3350, brake options clarified with M2300V now 50 lb penalty or Brembo alternative. · T3 BMW Spec E46 rules updated to Version 3.0 from Version 1.1. · 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. · T3 BMW Spec E46 updates to SpecE46 rules Version 1.1 dated Jan. 6, 2025. · T3 Ford Mustang V6 11-14 minimum weight drops 25 lbs to 3325. · T2 BMW M2 CS Cup requires Red power stick #8324085 instead of Purple #8324089; Corvette C5 Z06 restrictor reduces to 58mm from 59mm.showhide
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.
T3 Please change 2011-2014 Mustang V6 Spec Line to 2005-2014 #39558wordingneutralT3 Ford Mustang V6 Spec Line expands to include 2005-2010 chassis and body with 2011-2014 engine.
T3 Nissan 350Z Weight Request #39598weight -25 lbsfasterT3 Nissan 350Z DE Motor loses 25 lbs to 3100, HR Motor loses 25 lbs to 3250.
T3 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.
STL Weight adjustment for STL #39579weightslowerSTL minimum weights increase across all classes, 1300 cc gains 195 lbs to 1950, up to 1850 cc at 2500.
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.
T3 Request to Allow Spec Mustang to Touring 3 in Appendix M Trim #39196weight -50 lbsfasterT3 Ford Spec Mustang restrictor opens to 45mm, weight drops to 3400 lbs.
T3 Tire Help for Spec E9X in T3 #39222tyres & wheelsfasterT3 BMW Spec E9X tire width increases to 255 from 225; spec E9X tire or any DOT permitted.
T3 SpecE46 Tire Sizing #39292tyres & wheelsfasterT3 SpecE46 permitted tire width increases from 225 to 245.
T3 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.
T3 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.
T3 T3 Ecoboost Mustang clarification #39236wordingunclearT3 Ford Mustang EcoBoost loses optional 2-piece 355mm Brembo rotor brake kit option with 50 lb penalty.
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.
T3 Make the S2000 Competitive Again #38470tyres & wheelsfasterT3 Honda S2000 wheels grow to 17x9.0 front and 17x10 rear; tyres widen to 255 front and 275 rear.
T3 ND Gearset Request for T4 #39166wordingneutralT3 and T4 Mazda MX-5 Miata models add approved gear kit PT#-0000-02-6100 to notes.
T3 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.
STL Lotus Weight Reduction #38772weight -50 lbsfasterSTL/STU Lotus weight reduced: Evora GT4 to 2700 lbs, Elise Cup R to 2250 lbs, Elise/Exige SC to 2450-2550 lbs.
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.
T3 Incorrect Touring Heading #38451wordingneutralT2, T3, T4 Spec Lines table header changed from T2 to ET.
T3 correct letter 37421 #38204wordingunclearBMW Spec E46 in T3 updates to SpecE46 rules Version 3.0.
STL E&O: SMX Allowance in STL #37945wordingunclearSTL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1 instead of 2500 lbs; spec components removed, only alternative tires allowed.
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.
T3 S550 Mustang #38061weight -50 lbsfasterT3 Ford Mustang V6 15-17 weight drops 50 lbs to 3350, brake options clarified with M2300V now 50 lb penalty or Brembo alternative.
T3 correct letter 37421 #38204wordingunclearT3 BMW Spec E46 rules updated to Version 3.0 from Version 1.1.
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.
T3 SpecE46 Tire Change #37421wordingunclearT3 BMW Spec E46 updates to SpecE46 rules Version 1.1 dated Jan. 6, 2025.
T3 S197 Mustang V6 in T3 #37594weight -25 lbsfasterT3 Ford Mustang V6 11-14 minimum weight drops 25 lbs to 3325.
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.
Cal Club 2025 CALCL252025-02-22
1:54.963Nick Leverone · fastest of 16 · top 5 within 3.3s
1:55.682Nick Leverone · fastest of 17 · top 5 within 2.6s
110.4Ryan Gutile
1:55.965Roger Eagleton · fastest of 6 · top 5 within 5.4s
1:56.197Scotty B White · fastest of 6 · top 5 within 3.8s
111.5J. David Orem
+0.515squal +1.002s
100.4%qual 100.9%
1:54.065Oli Thordarson · fastest of 2
1:52.758Oli Thordarson · fastest of 2
114.4Oli Thordarson
-2.924squal -0.898s
97.5%qual 99.2%
411 earlier rule changes on record, in force before Cal Club 2025 (from 2019)75 cars added · 65 weight · 39 suspension & brakes · 32 induction · 25 tyres & wheels · 14 aero · 8 engine · 4 removed · 138 wording · 11 other · 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. · T3 Nissan 350Z HR Engine FPR restrictor increases from 47mm to 49mm. · 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. · 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. · T2, T3, T4 remove nine, nine, and thirty-six expired spec lines respectively, effective 2025-01-01. · Ford Spec Mustang moves to T3 with 44mm bore restrictor, 275 max tire, 3450 lbs minimum weight. · T3 Ford Mustang V6 (11-14) and (15-17) now permit cold air intake. · STL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval. · 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. · T3 VW Golf R (12-13 and 15-18) 36mm TIR placement now allows OEM turbo inlet, removing 60mm distance limit from impeller. · T2 and T3 Mustang spec lines remove redundant driveshaft alternate/aluminum allowance wording. · 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. · T3 and T4 Mazda RX-8 and MX-5 permit transmission kit #0000-02-5700. · Porsche Spec Boxster moves to T4, minimum weight 2750 lbs, requires 3 Super Tour events before Runoffs eligibility. · 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. · T3 BMW 328i/330i (06-12) model name updated; BMW 320i (14-15) newly classified at 3050 lbs. · T3 Subaru WRX STI max model year extended to 21, max tire size increased to 275. · T3 Honda HPD Civic Si FE1 newly classified with 1498cc engine, 18x8 wheels, 245 tires, 2950 lbs minimum weight. · T3 Subaru WRX STI 03-07 drops 100 lbs to 3200; Legacy GT/Spec B 05-09 drops 150 lbs to 3200. · T2 Spec Corvette now allows 295 R compound DOT tires as alternative to Nankang NS-2R. · 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. · T3 Honda Civic Si (2017-2021) restrictor removed, weight to 2950 lbs, Runoffs eligibility requires 3 Super Tour events. · T3 Subaru STI (15-20) and WRX STI (03-07) permitted to use OEM spec block #IAG-ENG-S550 and head studs. · Audi TT Coupe 08-14 classified in T3 with 36mm TIR restrictor, 1984cc, 3200 lbs minimum weight. · T3 Mazda MX5 Miata/Club/RF (19-24) newly classified at 2550 lbs, 17x8.5 wheels, 245 tyres, 280 mm brakes. · 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. · Ford Mustang GT 5.0L and V6 now permit Track/Performance Package parts in T2 and T3. · T2-T4 Ford Mustangs: remove 25 lbs penalty for non-OEM driveshaft, clarify alternate driveshaft allowances. · T3 Nissan 350Z DE engine now permits cold air intake. · Audi S4 (2000-2002) moves to T3 with 3400 lbs minimum weight, 38mm turbo inlet restrictor required. · T3 BMW Z4 3.0si expands to include 3.0i Roadster and Coupe (07-08); hardtop permitted with positive fasteners. · T3 Mazda MX-5 Global Cup Miata ND1/ND2 tire size changes to 225 DOT specification. · 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. · T3 and T4 Mazda RX-8 may remove or disable factory oil injection system. · T2, T3, T4 driveshafts may use alternative materials or one-piece units; non-OEM adds 25 lbs. · Audi S4 00-02 in T3 must compete in 3 Super Tour events before Runoffs eligibility. · T2 Porsche Cayman S 06-09 allows StopTech ST60/ST40 brake kit with 50 lb penalty. · 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. · T3 Spec Z 350Z rear wheel width increases to 10 inches; HR Engine restrictors change from 42mm to 44mm. · Audi S4 2000-2002 classified in T3 at 3400 lbs with 38mm turbo inlet restrictor required. · 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. · T3 Ford Mustang V6 (11-14) restrictor requirement removed; (15-17) brake penalty reduced to +50 lbs from +100 lbs. · T3 Nissan 350Z and 370Z now allow brake booster vacuum regulator, must not be in-car adjustable. · T3 Ford Mustang 4.6L restrictor holes increased from 40 mm to 45 mm. · T3 Mazda RX-8 Spec Line retention appeal directed to letter #35584 for ruling. · Mazda RX-8 04-12 expiration date removed; no longer expires 12/31/24. · T3 Subaru WRX (02-05) spec line expiration deadline removed; class now permanent. · STL and STU power steering rules clarified to permit electric-assisted and hydraulic-assisted steering systems. · STL Acura/Honda B-series and Mazda MZR restrictors reduced 2mm; minimum weights down 25–75 lbs for 1900–2000cc engines. · STL Mazda 12A must keep 5th and 6th intake port actuators and valves, no longer allowed removal or disabling. · 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. · T3 Golf R 15-18 max wheel width increases to 9 inches, max tire size to 255. · T2, T3, T4 battery replacement wording simplified; OEM weight tolerance requirement removed. · T3 Ford Mustang V6 (11-14) gains approved strut tower brace and sway bar kit options. · T3 Ford Mustang EcoBoost 2015- intake restrictor increases from 35mm to 36mm TIR. · 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. · STL Mazda RX-7 12A (79-85) now allows auto-type 2 bbl with 42mm choke(s) on dual-y manifold as alternate to stock Nikki 4 bbl. · 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. · T3 Pontiac Solstice GXP front brake rotor increases from 296 to 355 mm vented. · T3 Nissan 350Z DE motor loses 75 lbs to 3125; HR motor gains 47mm restrictors, up from 44mm. · T3 Nissan 370Z model years expanded to include NISMO Edition through 2022. · T3 2010 Mustang GT 4.6 now allows 2013-14 GT style front/rear fascia, hood, and associated assemblies. · T3 BMW SpecE46 minimum weight drops 50 lbs to 2850. · T3 Subaru STI (15-20) minimum weight increases 100 lbs to 3450; all three STI variants get larger turbo inlet restrictors. · T2 BMW M2 CS Cup 2020- permitted to add hood vents conforming to 9.1.9.2.D.8.a.7. · T3 Porsche Cayman (09-12) and (13-16) gear and final drive ratios adjusted; 09-12 6-SPD final drive 3.88 to 3.875, PDK 3.909 to 3.250; 13-16 6-SPD final drive 3.89 unchanged, PDK 3.91 to 3.250. · T3 Volkswagen GTI 06-10 turbo inlet restrictor increases from 36mm to 37mm. · T3 Volkswagen Golf R permitted model years extended from 15-16 to 15-18. · T3 Volkswagen Golf R 15-16 now permits Verkline WAS-048 camber arms. · BMW Spec E9X classified in T3 at 2975 lbs, must conform to SpecE9X rules Version 2.10, tire max 225. · T3 VW Golf GTI and Golf R TIR location clarified to maximum 60mm from impeller. · 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. · 2012-2013 Volkswagen Golf R added to T3 as new entry with 1984cc engine, 3080 lbs DSG/3050 STD, 36mm turbo inlet restrictor. · 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 Nissan 350Z and 370Z maximum tire width increases from 245 to 255. · 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. · T3 Camaro V6 1LE and LT-I4 Turbo 1LE max wheel diameter increases from 18 to 20 inches. · T3 removes Toyota 2022-up GR Cup and 2022-up GR86 Cup entirely from Spec Lines. · STL ITA/ITS RX7 and 1985+ ITA/ITS/ITB/ITC vehicles clarified to conform to section 9.1.4.2 tire specifications. · T2 Porsche Cayman S model year range extended from 06-08 to 06-09. · T3 Ford Mustang V6 (15-17) weight drops to 3400 lbs, brake penalties reduced to +100 lbs and +50 lbs. · BMW SpecE46 in T3 loses 50 lbs, to 2900. · T3 adds 2022 Toyota GR Cup and GR86 Cup, both 2387cc, 2700 lbs, 245/620R18 slicks, 332x32F/280x32R brakes. · T2 Chevrolet Corvette C5 Z06 restrictor increases from 53mm to 56mm; 58mm option removed. · T3 BMW Spec E46 weight reduced 25 lbs, to 2925. · T3 BMW 323Ci/Is weight reduces to 2750 lbs from 3000 lbs. · T3 BMW SpecE46 must conform to SpecE46 rules Version 2.10, updated from 2.7. · 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. · T3 06-10 VW GTI, Jetta GLI allowed to use ECS Tuning performance alternative intercooler. · T2 Honda Civic Type-R tire size increases from 275 to 295. · T3 Porsche Spec Boxster tire rule updates to current SPB rules or any 245 DOT tire. · T3 06-10 VW GTI and Jetta permitted to use OEM VW knuckles 3C0407253F and 3C0407254F. · T3 BMW 320I now permitted to use aftermarket intercooler. · 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. · Porsche Cayman (13-16) classified in T3 at 3225 lbs with 2700cc engine, 18x9 wheels, 245 tires. · T2/T3 Mustang GT 5.0L and V6 (11-14) may remove upper grille fog lights, replace with mesh or screen. · Hyundai Veloster Turbo 2018-2021 classified in T3 at 3050 lbs with 1584cc engine, 245 max tire size, specific suspension and brake modifications allowed. · T3 Volkswagen GTI and Jetta GLI now permit Verkline WAS-048 adjustable rear camber arms. · STL Spec MX5 clutch, wheels, and tyres specified: ACT 0000-02-5004-G6, 17x8 wheels, Toyo RR and RA1 235-40-17. · 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. · T3 Nissan 350Z and 370Z remove SPC Control Arms 72130, 72125, 72123; permit performance alternative front upper control arms. · T3 Nissan 350Z loses up to 75 lbs and gets 44mm restrictors; 370Z loses 100 lbs. Wheels widened front and rear. · T3 Ford Mustang EcoBoost 2015- turbo inlet restrictor increases from 34mm to 35mm TIR. · 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. · T2 Dodge Viper SRT-10 wheel size 18x11 rear, weight to 3675 lbs, throttle restrictor hole 44mm convertible or 42mm hardtop. · T3 Solstice GXP intercooler options expanded: Hahn HIC-1150 or Dejon FIC-SSA replaced with Performance alternative. · T3 Subaru BRZ 2022- minimum weight up to 2975 lbs; spring rate to 1000 F/R, brake parts allowed without penalty. · T3 Honda S2000 hardtop clarified: OEM, Mugen P/N 0000-04-2312, or aftermarket permitted if OEM roof silhouette retained. · T3 Pontiac Solstice GXP Coupe/Convertible 07-09 tire runout increases from 35mm to 36mm TIR. · BMW 320i (14-15) classified in T3 at 3050 lbs with 18-inch wheels, 255/275 tires, 3.08 final drive. · T3 Subaru BRZ (2022-) and Toyota GR86 (2022-) permit 25mm front and 22mm rear sway bars, OEM trunk spoiler. · 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. · 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. · T3 Honda Civic Si (2017-) spec clarified: wheels to 10" wide allowed with 50 lb. penalty, 1-piece rotor required. · Porsche Boxster Base 2005-2008 newly classified in T3 at 3000 lbs minimum weight. · T2-T4 Touring cars with alternative springs may use performance top hats with spherical bearings on shocks and struts. · T3 Subaru BRZ and Toyota 86 (2022-) wheel size corrected to 18 x 8 in., gear ratios and final drive specified. · 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. · T2-T4 cars model year 2018+ may use non-OEM ECU with 75 lb weight penalty via spec line adjustment. · T3 Ford Mustang V6 (11-14) minimum weight reduced to 3350 lbs. · T3 Subaru STI 15-20 now allows SPC lower control arm 67660. · STU normally aspirated engines: minimum weights reduced up to 310 lbs; single throttle body weight reduction removed. · STL and STU Improved Touring vehicles must conform to 9.1.4 Tires & Wheels requirements. · 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. · T3 BMW 330i/Ci 01-06 loses 60 lbs to 3125 and runs 245 tyres instead of 275. · T3 Nissan 370Z 09-16 and 370Z NISMO 09-13 weight increased to 3375 lbs. · T3 FWD models standardized to 36mm turbo inlet restrictor; Focus ST brakes enlarged, final drive changed to 4.06 (1-4) 2.95 (5-6); GTI 14.5-17 gear ratios revised DSG/STD. · T2-T4 grill openings may remove non-metallic webbed false sections; 16 square inch limit removed. · T3 Spec Lines Subaru BRZ TS (13-21) added to class specification wording. · T3 VW GTI/Jetta GLI allows any 4-piston brake kit instead of StopTech only, max 355mm x 32mm. · T2 BMW Z4M 06-08 weight reduced from 3150 to 3100 lbs. · STL and STU piston engines clarified: intake manifold and cylinder head porting remains free. · STL Mazda Renesis flat plate restrictor increases from 55mm to 60mm. · STL Mazda RX-7 12A 79-85 clarifies carburetor, emissions, and water jacket modification rules. · 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. · T3 Scion FR-S/Toyota 86 GT and Subaru BRZ lose 75 lbs, to 2675 lbs minimum weight. · 2022+ Subaru BRZ and Toyota 86 newly classified in T3 at 2750 lbs with 245 max tires. · T2-T4 clarified: grill opening area may increase max 16 sq in for radiator cooling only, retaining factory mesh shape. · T3 BMW 335i eligible model years narrowed from 08-13 to 07-10. · T3 BMW 135i model years restricted from 08-13 to 08-10. · T2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted. · T3 Nissan Z 350Z and 370Z suspension control arm options expanded from 'and' to 'or' for SPC parts. · T2, T3, T4 clarify that spec lines listing permitted or allowed parts are alternatives to category rules, not replacements. · T2 BMW M2 CS Cup 2020 rear brake rotor reduced from 390 mm to 380 mm. · T3 BMW Z4 M Coupe model years corrected from 2007 to 06-08. · T3 Subaru STI 15-20 weight increases 150 lbs, to 3350. · 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. · T4 Volkswagen Passat, Jetta 1.8T adds 2014 model year to eligible years. · T3 BMW 323Ci/Is 98-00 minimum weight reduced from 3100 to 3000 lbs. · Subaru STI (15-20) newly classified in T3 at 3200 lbs minimum weight with 37mm turbo inlet restrictor required. · STL Spec MX-5 removes redundant specification line; no performance change. · T2 BMW M2 CS Cup 2020- must run Purple power stick, part #8324089 instead of #TBD. · T2 Porsche 911/997.1 (06-08) now allows alternate Cargraphics CARP97DFIFKR exhaust manifold. · T2 BMW M2 CS Cup 2020- weight increases from 3625 to 3600 lbs; mandatory Purple power stick added. · T3 Porsche Spec Boxster minimum weight reduced from 2600 to 2550 lbs. · T3 Porsche Cayman 06-08 wheel size changes from 18x8 to 18x9 inches. · T3 Mazda MX-5 Global Cup Miata ND2 with sequential gearbox allowed +100 lbs weight adder. · STL Volkswagen 2.0L TFSI 1984cc classified with turbocharger removal required, meeting all other STL specs. · 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. · T3 Honda Civic Type-R 2020+ allows brake rotor 45251-TGH-A01 with 25 lb penalty. · STL Pontiac Solstice/Saturn Sky allowed 4" ride height. · STL Mazda B5 DOHC added to classification with standard STL regulations. · STL Honda B16A JDM restrictor reduced from 54mm to 53mm. · 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. · T3 Porsche Boxster/Boxster S (00-04) now permits any OEM or aftermarket hardtop retaining OEM roof silhouette. · T3 Mazdaspeed3 07-09 and 10-13 now allow CorkSport Gen-6-999-10 or Autotech 10-127-100K fuel pumps. · ST oil coolers and filters now explicitly allowed to be added or substituted; wording clarifies existing permissions. · 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-T4 clutch disc and pressure plate must be at least 95% of factory OEM weight. · Porsche Cayman 06-08 classified in T3 with 2687cc engine, 3050 lbs minimum weight, 18-inch wheels, 245 tires. · STL GM Ecotec engines now permit any combination within the family, must use 55mm flat plate restrictor. · STL/STU 90-05 Mazda Miata gains approval for Mazda Motorsports Development alternate front wheel hubs. · T2 BMW M2 CS Cup 2020- permitted to remove door glass and mechanism. · T3 Ford Mustang EcoBoost gets 35mm TIR; Nissan 350Z DE Motor down 25 lbs to 3250; Mustang V6 down 50 lbs to 3475, restrictor tightened 55mm to 58mm. · ST cars may relocate ABS actuation hardware and wiring anywhere in engine compartment. · STL rear wing trailing edge, including end plates and gurney flap, maximum rearward mounting clarified to center of rearmost bodywork. · STL allows OEM gear sets from same manufacturer transmissions with input shaft modifications for fitment. · 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. · Toyota Supra 2020- newly classified in T2 at 3450 lbs minimum weight with 295 tire and 19-inch wheels. · T3 Chevrolet Camaro LT-I4 Turbo 1LE reclassified to 2016- model year, max tire size 275, TIR required 35mm. · 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. · T3 Spec Boxster tire size increased from 225 to 245 DOT, permitting wider tires. · STL RWD strut suspension weight penalty cut to 0.5%, other RWD cut to 2.5%. · STL Honda F20C loses 2% weight penalty, minimum weight reduced by approximately 35 lbs. · STL Honda B16/B17/B18C1 restrictor tightened to 53mm; B18C variants and Mazda MZR to 52mm. · 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. · BMW M2 CS Cup 2020+ classified in T2 at 3625 lbs with 2979cc engine, 10.5x18 wheels, 295 tires. · T3 and T4 Mazda MX-5 06-15 now allow Mazda Transmission kit part # 0000-02-5700. · 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. · ST aero devices and reference areas now include end plates but exclude fasteners protruding over 1/2 inch. · 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. · 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. · Honda Civic Type R (2017-) classified in T3 at 3350 lbs with 1996cc engine, 245 max tire, 20-inch max wheel. · 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. · STL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis adjustments. · STL and STU rear wing rules clarify that wicker is a Gurney flap; no performance change. · T2 Ford Mustang EcoBoost and GT 5.0L gain three optional gear ratio sets for competition use. · T3 Honda Accord (2009) V6 manual classified: 3471cc, 3450 lbs, 245 max tire, 19-inch wheels. · 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. · T3 Mazda MX-5 Global Cup Miata ND2 2016-2019 must meet all ND2 Global Cup rules without appendix reference. · T3 VW GTI FSI gains turbo inlet restrictor allowance to 60mm, R32 brakes, Stoptech 4-piston kit, and Neuspeed intake options. · Cannot read: letter references external document #27663 not provided. · STL adds 2016-2019 Mazda MX-5 Global Cup at 2000cc, 2450-2550 lbs minimum weight. · STL Mazda MX-5 Club Model 06-15 allows Mazda header part number 0000-06-5407-NC. · STL Honda/Acura B18 non-C gets 54mm restrictor; B18C variants drop B18C1, get 53mm restrictor. · 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. · 2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine and Eibach PN# 2563.140 springs allowed. · T3 Nissan 350Z Spec 2 DE Engine loses 57mm flat plate restrictor requirement. · STL Honda B18 restrictor reduced from 54mm to 53mm flat plate; B18C1 added with 54mm restrictor. · 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. · T3 Ford Mustang EcoBoost and V6 sway bars allowed up to 35mm front, 25mm rear. · T3 BMW Z3 M & Coupe 1998-1999 weight reduced from 3350 to 3150 lbs. · STU GM Ecotech LNF now allowed with turbo removed or with LE5 head and intake manifold, meeting STL specs. · STL Mazda MZR restrictor reduced from 54 mm to 53 mm. · STL Mazda MZR restrictor reduced from 55 mm to 53 mm. · 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. · STL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL. · T2 Porsche 911/997 (06-08, 09-12, Carrera S 06-08) aero rules relaxed; 997.2 adds 60mm restrictor and PDK +100lbs option. · T3 05-10 V8 Mustang allowed parts clarified: strut tower brace, radiator, springs to 500 lbs/in front and 300 lbs/in rear, sway bars, damper kit. · T3 Ford Mustang Coupe GT & Shelby GT 4.6L 05-10 adds permitted final drive ratios: 3.31, 3.55 or 3.73. · 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. · BMW 330i 2006-2012 added to T3 with 2996cc engine, 3200 lbs minimum weight. · 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. · Mazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01. · T3 adds 2017 Ford Fiesta ST, 1596cc, 2600 lbs minimum weight, 245 max tire, 17x9 wheels. · 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. · 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. · T3 Nissan 350Z and 370Z HR engines: restrictor plate enlarged from 37mm to 42mm, weight increased 50-100 lbs. · T3 Mazda MX-5 Global Cup Miata (2016-) tires now 215/610 R17 BF Goodrich G-Force Slick or wet; removes touring tire requirement. · T3 05-10 Mustang GT 4.6L suspension upgrades allowed: tower braces, radiator, 500/300 lbs/in springs, sway bars, dampers, control arms, shocks, driveshaft. · T3 BMW SpecE46 updates to SpecE46 rules Version 2.6 to 2.7, tire width to 225 maximum. · T3 Subaru WRX 02-05 minimum weight drops 100 lbs to 3250. · 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. · T3 Scion FR-S/Toyota 86 and Subaru BRZ year range extended from 13-17 to 13-20. · Mazda Spec MX-5 Challenge classified in STL with 2000cc displacement and 2500 lbs minimum weight. · T3 Mazda NC MX-5 gains two alternate six-speed and one five-speed transmission gear ratio option. · T2-T4 spare tire/wheel rules clarified: removable covers can be removed with hardware and bracketry. · T2-T4 spare tire/wheel rules clarified: removable covers can be removed with hardware and bracketry. · T3 Mk7 GTI gains R32 brake package, 4-piston Stoptech kit to 355mm, and ECS street shield allowance. · STU alternate intake manifolds now allowed case-by-case instead of prohibited. · 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. · T3 BMW E36 M3 96-00 allows alternate sway bars, 35mm front and 27mm rear. · STL Acura/Honda B18 except C engine restrictor increases from 53mm to 54mm flat plate. · 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. · 09-12 Porsche Cayman newly classified in T3 at 3150 lbs with 2900cc engine. · STL and STU ride height measurement clarified: without driver, at rocker panel lowest point, excluding pinch weld. · T3 Chevrolet Camaro LT-I4 Turbo 1LE (2019-) classified with 1998 cc engine, 3450 lbs minimum weight, 245 max tire size. · T3 Honda Civic Si 2017- minimum weight reduced 100 lbs, to 2900. · Honda Civic Si 2017+ with alternate cage classified in T3 at 3075 lbs minimum weight. · T3 classifies 2014-2017 Volkswagen GTI with 35 mm turbo inlet restrictor, 3080 lbs DSG, 3050 lbs standard. · T2 Mustang GT anti-roll bars may now be removed or disconnected, previously required as manufactured. · BMW E36 M3 (96-00) BMWCCA I Sport newly classified in T3 at 3100 lbs minimum weight. · STL adds VW 1.8L R4 20VT 1781cc, 1 minimum weight, turbo removed permitted. · STL Mazda Renesis minimum weight reduced from 2800 to 2700 lbs. · STL Mazda MX-5 Cup brake pad compound changed to open. · STL adds Acura/Honda B18C1 GSR with 54mm flat plate restrictor and port matching limited to 1 inch. · STL Mazda 12 and 13B now permit port matching; previous ban removed. · 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. · T1-LP Ford Mustang GT 5.0L 2018+ classified at 3400 lbs with 65mm flat plate restrictor. · T3 Subaru WRX (2015-) classified at 3275 lbs with 35mm turbo inlet restrictor required. · 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. · T3 Mazda MX-5 NC 06-15 wheel width increases from 17x7 to 17x8. · T3 Mazda MX-5 NC 06-15 now allows any aftermarket header. · T3 Saturn Sky intercooler tolerance increases from 32mm to 35mm TIR; new calipers and springs permitted. · T2, T3, T4 now allow any thermostat serving only OE intent, previously restricted. · T3 Subaru Legacy GT/Spec B 05-09 newly classified with 2457cc, 18×9 wheels, 245 tires, 3300 lbs. · T3 and T4 Mazda MX-5 Miata eligibility capped at 2018 model year, effective 2019-03-01. · T3 Mazda Mazdaspeed3 07-09 front brake disc increases to 320mm vented, rear to 300mm solid. · STL B18C Type R variants get 54mm flat plate restrictor; B17 also gets 54mm restrictor. · STL Mazda Miata removes maximum displacement limit and adjusts minimum weight. · 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. · T4 Ford Fiesta ST years corrected to 14-; T4 Fiat 124/Abarth Edition years added 16-18; battery rule clarified. · T3 BMW SpecE46 rules reference updated from Appendix N to Version 2.6 Effective Jan 1, 2019. · T3 Nissan 350Z Track/Touring/Standard/Nismo 03-08 permitted to use Nissan brake kit part number 41000-BRKIT. · 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. · T3 field loses 50 lbs across 27 cars including Acura TL, BMW 335i, Camaro, Mustang, Miata, RX-8, 370Z, WRX. · T3 Ford Mustang EcoBoost gains Ford Motorsports or Brembo brake kit options, +100 lb. · T3 FR-S/86 and BRZ: wheels to 17x9, tires to 255, weight to 2750 lbs. · T3 BMW SpecE46 now permits any DOT tire up to 225 width as alternate to spec tire.showhide
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.
T3 350z BOP #37427inductionfasterT3 Nissan 350Z HR Engine FPR restrictor increases from 47mm to 49mm.
T3 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.
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.
T3 Remove spec lines that have expired #37269removedneutralT2, T3, T4 remove nine, nine, and thirty-six expired spec lines respectively, effective 2025-01-01.
T3 Request to Move Spec Mustang to Touring 3 (from T2) #37080cars addedneutralFord Spec Mustang moves to T3 with 44mm bore restrictor, 275 max tire, 3450 lbs minimum weight.
T3 3.7 Mustangs BoP #37186inductionfasterT3 Ford Mustang V6 (11-14) and (15-17) now permit cold air intake.
STL Request to Remove Miata Hubs from General category #37138wordingneutralSTL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval.
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.
T3 Amend TIR Placement on VW #36175wordingneutralT3 VW Golf R (12-13 and 15-18) 36mm TIR placement now allows OEM turbo inlet, removing 60mm distance limit from impeller.
T3 Redundant Verbiage Regarding Mustang Spec Lines for Driveshaft #36484wordingneutralT2 and T3 Mustang spec lines remove redundant driveshaft alternate/aluminum allowance wording.
T3 Fuel Emissions Components #37076wordingneutralT2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors.
T3 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.
T3 Evaporative emissions systems #37130wordingneutralT2, T3, T4 fuel cell cars may remove charcoal canisters, emissions valves, and sensors.
T3 Allow Spec MX5 upgrade kit for 2009-11 RX8 S2 Transmision #37140wordingneutralT3 and T4 Mazda RX-8 and MX-5 permit transmission kit #0000-02-5700.
T3 Move Spec Boxster to T4 #37158cars addedneutralPorsche Spec Boxster moves to T4, minimum weight 2750 lbs, requires 3 Super Tour events before Runoffs eligibility.
T3 BMW 320i Spec Line #37204wordingneutralT4 BMW 320i 14-15 Spec Line expires 12/31/24 removed; Turner Motorsports intercooler #024703TMS02 allowed.
T3 Classification for a 2005 Cadillac CTS 3.6 liter 6 speed manual #37224cars addedneutralCadillac CTS 02-07 3.6L classified in T3.
T3 Request to Classify BMWs #37226cars addedneutralT3 BMW 328i/330i (06-12) model name updated; BMW 320i (14-15) newly classified at 3050 lbs.
T3 Make adjustments to the 2015 STI Spec line #37246tyres & wheelsfasterT3 Subaru WRX STI max model year extended to 21, max tire size increased to 275.
T3 class a civic #37294cars addedneutralT3 Honda HPD Civic Si FE1 newly classified with 1498cc engine, 18x8 wheels, 245 tires, 2950 lbs minimum weight.
T3 Older STI in T3 #37300weight -100 lbsfasterT3 Subaru WRX STI 03-07 drops 100 lbs to 3200; Legacy GT/Spec B 05-09 drops 150 lbs to 3200.
T2 Spec Corvette Change for T2 #37127tyres & wheelsneutralT2 Spec Corvette now allows 295 R compound DOT tires as alternative to Nankang NS-2R.
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.
T3 Honda Civic Si (2017+) #36249inductionfasterT3 Honda Civic Si (2017-2021) restrictor removed, weight to 2950 lbs, Runoffs eligibility requires 3 Super Tour events.
T3 Subaru Reliability Help #36284wordingneutralT3 Subaru STI (15-20) and WRX STI (03-07) permitted to use OEM spec block #IAG-ENG-S550 and head studs.
T3 spec line for 36073 #36338cars addedneutralAudi TT Coupe 08-14 classified in T3 with 36mm TIR restrictor, 1984cc, 3200 lbs minimum weight.
T3 36131 #36339cars addedneutralT3 Mazda MX5 Miata/Club/RF (19-24) newly classified at 2550 lbs, 17x8.5 wheels, 245 tyres, 280 mm brakes.
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.
T3 Mustang T2/T3 #35877wordingunclearFord Mustang GT 5.0L and V6 now permit Track/Performance Package parts in T2 and T3.
T3 T2-T4 Driveshaft Mistake...? #36050weightfasterT2-T4 Ford Mustangs: remove 25 lbs penalty for non-OEM driveshaft, clarify alternate driveshaft allowances.
T3 E&O: #35174 (Derek Chan) 350Z Parity Request #36116inductionfasterT3 Nissan 350Z DE engine now permits cold air intake.
T3 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.
T3 Z4 Roadster Eligibility #36196cars addedneutralT3 BMW Z4 3.0si expands to include 3.0i Roadster and Coupe (07-08); hardtop permitted with positive fasteners.
T3 Global MX5 Tre change #36046tyres & wheelsunclearT3 Mazda MX-5 Global Cup Miata ND1/ND2 tire size changes to 225 DOT specification.
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.
T3 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.
T3 Driveshafts #35916weightslowerT2, T3, T4 driveshafts may use alternative materials or one-piece units; non-OEM adds 25 lbs.
T3 Audi S4 HST requirement #35918wordingneutralAudi S4 00-02 in T3 must compete in 3 Super Tour events before Runoffs eligibility.
T2 Brake Request for 2009 Porsche Cayman #35723suspension & brakesslowerT2 Porsche Cayman S 06-09 allows StopTech ST60/ST40 brake kit with 50 lb penalty.
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.
T3 Spec Z Interchange in T3 #34416tyres & wheelsfasterT3 Spec Z 350Z rear wheel width increases to 10 inches; HR Engine restrictors change from 42mm to 44mm.
T3 please classify 2000-2002 Audi s4 #35306cars addedneutralAudi S4 2000-2002 classified in T3 at 3400 lbs with 38mm turbo inlet restrictor required.
T3 Reorganize Spec Lines #35375wordingunclearT2-T4 Spec Lines remove wheelbase requirement, replace with Required Restrictor specification.
T3 370Z Brake Rotor Size Correction #35487suspension & brakesneutralT2 and T3 Nissan 370Z brake rotors enlarged: front 320x28 to 355x32mm, rear 320x16 to 350x20mm vented.
T3 T3 V6 Mustang help #35526enginefasterT3 Ford Mustang V6 (11-14) restrictor requirement removed; (15-17) brake penalty reduced to +50 lbs from +100 lbs.
T3 Nissan 370Z - Brake System Allowance - Brake Booster #35556suspension & brakesneutralT3 Nissan 350Z and 370Z now allow brake booster vacuum regulator, must not be in-car adjustable.
T3 Mustang Help #35559inductionfasterT3 Ford Mustang 4.6L restrictor holes increased from 40 mm to 45 mm.
T3 Appeal for Retention of T3 Mazda RX-8 Spec Line (Letter #35378) #35577wordingunclearT3 Mazda RX-8 Spec Line retention appeal directed to letter #35584 for ruling.
T3 Request to Keep the Mazda Rx-8 in Touring 3 #35584wordingneutralMazda RX-8 04-12 expiration date removed; no longer expires 12/31/24.
T3 Subaru WRX (02-05) Appeal #35656wordingneutralT3 Subaru WRX (02-05) spec line expiration deadline removed; class now permanent.
STL ST Electric-Assisted Steering Systems #35066wordingneutralSTL and STU power steering rules clarified to permit electric-assisted and hydraulic-assisted steering systems.
STL BOP Adjustments #35112inductionfasterSTL Acura/Honda B-series and Mazda MZR restrictors reduced 2mm; minimum weights down 25–75 lbs for 1900–2000cc engines.
STL Mazda 12A #35320engineslowerSTL Mazda 12A must keep 5th and 6th intake port actuators and valves, no longer allowed removal or disabling.
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.
T3 15-18 Golf R Alignment with Existing GTI and R Speclines #35235tyres & wheelsfasterT3 Golf R 15-18 max wheel width increases to 9 inches, max tire size to 255.
T3 More Car Lightening Stuff #35319weightfasterT2, T3, T4 battery replacement wording simplified; OEM weight tolerance requirement removed.
T3 Open Strut Tower Brace Options for Ford Mustang V6 (11-14) #35322wordingneutralT3 Ford Mustang V6 (11-14) gains approved strut tower brace and sway bar kit options.
T3 Mustang ecoboost #35351inductionfasterT3 Ford Mustang EcoBoost 2015- intake restrictor increases from 35mm to 36mm TIR.
T3 Inclusion of B-C spec cars in T4 #35374cars addedneutralT4 now permits C-Spec cars to compete alongside B-Spec cars.
T3 T2-T4 Set expiration dates on spec lines #35378wordingneutralT2-T4 spec lines for 46 cars expire 12/31/24; appeal required to continue.
STL Alternate Carburetor Request for 79-85 RX7 12a #35181inductionunclearSTL Mazda RX-7 12A (79-85) now allows auto-type 2 bbl with 42mm choke(s) on dual-y manifold as alternate to stock Nikki 4 bbl.
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.
T3 T3 Solstice Brakes #35106suspension & brakesslowerT3 Pontiac Solstice GXP front brake rotor increases from 296 to 355 mm vented.
T3 350Z Parity Request #35174weightslowerT3 Nissan 350Z DE motor loses 75 lbs to 3125; HR motor gains 47mm restrictors, up from 44mm.
T3 Requested Update of Model Years of 370Z #35231wordingneutralT3 Nissan 370Z model years expanded to include NISMO Edition through 2022.
T3 Update Request for 2010 Mustang GT 4.6 #35234wordingneutralT3 2010 Mustang GT 4.6 now allows 2013-14 GT style front/rear fascia, hood, and associated assemblies.
T3 SE46 Continued Parity/ Cold Air Intake request #35267weight -50 lbsfasterT3 BMW SpecE46 minimum weight drops 50 lbs to 2850.
T3 Please help the Subaru STIs. #35278weight +100 lbsslowerT3 Subaru STI (15-20) minimum weight increases 100 lbs to 3450; all three STI variants get larger turbo inlet restrictors.
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.
T3 Porsche Cayman Transmissions and Ratios #34891wordingfasterT3 Porsche Cayman (09-12) and (13-16) gear and final drive ratios adjusted; 09-12 6-SPD final drive 3.88 to 3.875, PDK 3.909 to 3.250; 13-16 6-SPD final drive 3.89 unchanged, PDK 3.91 to 3.250.
T3 2006-10 Volkswagen GTI - Weight Reduction request and KO4 Turbo #34414inductionfasterT3 Volkswagen GTI 06-10 turbo inlet restrictor increases from 36mm to 37mm.
T3 Adding Model Years to T3 Golf R Spec Line #34612wordingneutralT3 Volkswagen Golf R permitted model years extended from 15-16 to 15-18.
T3 Rear Camber Arms for T3 VW Golf R #34613wordingneutralT3 Volkswagen Golf R 15-16 now permits Verkline WAS-048 camber arms.
T3 Classing Spec E90 Cars in SCCA #34791cars addedneutralBMW Spec E9X classified in T3 at 2975 lbs, must conform to SpecE9X rules Version 2.10, tire max 225.
T3 TIR location requirement in VW Golf Spec lines #35048wordingneutralT3 VW Golf GTI and Golf R TIR location clarified to maximum 60mm from impeller.
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.
T3 2012-2013 Golf R - added to T3 #34413cars addedneutral2012-2013 Volkswagen Golf R added to T3 as new entry with 1984cc engine, 3080 lbs DSG/3050 STD, 36mm turbo inlet restrictor.
T3 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.
T3 rule book corrections #34437otherfasterT3 BMW 320i (14-15) gains aftermarket intercooler permission; T4 loses it.
T3 Allowing 255 Tire Width for Nissan 350z #34471tyres & wheelsfasterT3 Nissan 350Z and 370Z maximum tire width increases from 245 to 255.
T3 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.
T3 2016+ Camaro 1LE - Max Wheel Diameter #34003tyres & wheelsfasterT3 Camaro V6 1LE and LT-I4 Turbo 1LE max wheel diameter increases from 18 to 20 inches.
T3 2022 Toyota GR Cup for T3 #34448removedneutralT3 removes Toyota 2022-up GR Cup and 2022-up GR86 Cup entirely from Spec Lines.
STL Clarify STL table B - IT spec notes on Tires #34187wordingneutralSTL ITA/ITS RX7 and 1985+ ITA/ITS/ITB/ITC vehicles clarified to conform to section 9.1.4.2 tire specifications.
T2 2009 Porsche Cayman Classing Request #34147wordingneutralT2 Porsche Cayman S model year range extended from 06-08 to 06-09.
T3 S550 Reconcile With S197 #34093weight -75 lbsfasterT3 Ford Mustang V6 (15-17) weight drops to 3400 lbs, brake penalties reduced to +100 lbs and +50 lbs.
T3 SE46 Parity Help #34178weight -50 lbsfasterBMW SpecE46 in T3 loses 50 lbs, to 2900.
T3 2022 Toyota GR Cup for T3 discussion #34234cars addedneutralT3 adds 2022 Toyota GR Cup and GR86 Cup, both 2387cc, 2700 lbs, 245/620R18 slicks, 332x32F/280x32R brakes.
T2 C5 Z06 Straight Line Speed #33575inductionslowerT2 Chevrolet Corvette C5 Z06 restrictor increases from 53mm to 56mm; 58mm option removed.
T3 Request Spec E46 in T3 Weight Adjustment #33897weight -25 lbsfasterT3 BMW Spec E46 weight reduced 25 lbs, to 2925.
T3 E36 2.5L 323is Weight Reduction #33975weightfasterT3 BMW 323Ci/Is weight reduces to 2750 lbs from 3000 lbs.
T3 Update SpecE46 Spec Line to Current SpecE46 Ruleset #34016wordingunclearT3 BMW SpecE46 must conform to SpecE46 rules Version 2.10, updated from 2.7.
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.
T3 Request to all ECS Tuning inner-cooler to 06-10 VW GTI spec #33769wordingneutralT3 06-10 VW GTI, Jetta GLI allowed to use ECS Tuning performance alternative intercooler.
T2 Honda Civic Type R Tire Size Increase #33672tyres & wheelsfasterT2 Honda Civic Type-R tire size increases from 275 to 295.
T3 T3 Boxster S GCR request #33687wordingneutralT3 Porsche Spec Boxster tire rule updates to current SPB rules or any 245 DOT tire.
T3 OEM VW Steering Spindle Replacements 06-10 VW GTI and Jetta #33732wordingneutralT3 06-10 VW GTI and Jetta permitted to use OEM VW knuckles 3C0407253F and 3C0407254F.
T3 BMW 320I intercooler #33762otherfasterT3 BMW 320I now permitted to use aftermarket intercooler.
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.
T3 Request to classify 2014 Base Cayman #33159cars addedneutralPorsche Cayman (13-16) classified in T3 at 3225 lbs with 2700cc engine, 18x9 wheels, 245 tires.
T3 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.
T3 Hyundai Classification #33498cars addedneutralHyundai Veloster Turbo 2018-2021 classified in T3 at 3050 lbs with 1584cc engine, 245 max tire size, specific suspension and brake modifications allowed.
T3 Adjustable Rear Camber Arms for VW (All Generations) #33572wordingneutralT3 Volkswagen GTI and Jetta GLI now permit Verkline WAS-048 adjustable rear camber arms.
STL Spec MX5 in STL #33473wordingneutralSTL Spec MX5 clutch, wheels, and tyres specified: ACT 0000-02-5004-G6, 17x8 wheels, Toyo RR and RA1 235-40-17.
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.
T3 350z SPC Upper Control Arm Safety Concerns #33020suspension & brakesneutralT3 Nissan 350Z and 370Z remove SPC Control Arms 72130, 72125, 72123; permit performance alternative front upper control arms.
T3 Request Help for 350z #33379weight -100 lbsfasterT3 Nissan 350Z loses up to 75 lbs and gets 44mm restrictors; 370Z loses 100 lbs. Wheels widened front and rear.
T3 Ecoboost Acknowledgement #33506inductionfasterT3 Ford Mustang EcoBoost 2015- turbo inlet restrictor increases from 34mm to 35mm TIR.
T3 Touring (T2-T5) Category #33617cars addedneutralT5 class added as regional-only; T5 tyres maximum width 225, minimum aspect ratio 45.
T3 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.
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.
T3 Solstice GXP in T3 #33501wordingneutralT3 Solstice GXP intercooler options expanded: Hahn HIC-1150 or Dejon FIC-SSA replaced with Performance alternative.
T3 Another 2022 BRZ/86 T3 request #32945weight +225 lbsslowerT3 Subaru BRZ 2022- minimum weight up to 2975 lbs; spring rate to 1000 F/R, brake parts allowed without penalty.
T3 S2000 Hard Top Clarification #32779wordingneutralT3 Honda S2000 hardtop clarified: OEM, Mugen P/N 0000-04-2312, or aftermarket permitted if OEM roof silhouette retained.
T3 T3 Pontiac Solstice- #33081tyres & wheelsslowerT3 Pontiac Solstice GXP Coupe/Convertible 07-09 tire runout increases from 35mm to 36mm TIR.
T3 Classify Car #32691cars addedneutralBMW 320i (14-15) classified in T3 at 3050 lbs with 18-inch wheels, 255/275 tires, 3.08 final drive.
T3 2022 BRZ Sway bar and lip spoiler. #32703suspension & brakesfasterT3 Subaru BRZ (2022-) and Toyota GR86 (2022-) permit 25mm front and 22mm rear sway bars, OEM trunk spoiler.
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.
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.
T3 correct wording #31750wordingneutralT3 Honda Civic Si (2017-) spec clarified: wheels to 10" wide allowed with 50 lb. penalty, 1-piece rotor required.
T3 2005-2008 Porsche Boxster 2.7 #31999cars addedneutralPorsche Boxster Base 2005-2008 newly classified in T3 at 3000 lbs minimum weight.
T3 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.
T3 2022 Subaru BRZ and Toyota 86 twins #32483wordingneutralT3 Subaru BRZ and Toyota 86 (2022-) wheel size corrected to 18 x 8 in., gear ratios and final drive specified.
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.
T3 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.
T3 T3 Mustang V8/V6 #31959weight -50 lbsfasterT3 Ford Mustang V6 (11-14) minimum weight reduced to 3350 lbs.
T3 Subaru STI (15-20) Missing part #32294suspension & brakesneutralT3 Subaru STI 15-20 now allows SPC lower control arm 67660.
STL Single TB Weight Modifiers #31449weightfasterSTU normally aspirated engines: minimum weights reduced up to 310 lbs; single throttle body weight reduction removed.
STL Improved Touring Tires #32063tyres & wheelsneutralSTL and STU Improved Touring vehicles must conform to 9.1.4 Tires & Wheels requirements.
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.
T3 Touring 3 BOP adjustments for 2022 #31481weight +75 lbs
T3 BMW 330i Minimum Comp Weight #31606tyres & wheels -60 lbsfasterT3 BMW 330i/Ci 01-06 loses 60 lbs to 3125 and runs 245 tyres instead of 275.
T3 Adjust T3 370Z #31748weight +50 lbsslowerT3 Nissan 370Z 09-16 and 370Z NISMO 09-13 weight increased to 3375 lbs.
T3 TIR changes for FWD T3 models #31825inductionfasterT3 FWD models standardized to 36mm turbo inlet restrictor; Focus ST brakes enlarged, final drive changed to 4.06 (1-4) 2.95 (5-6); GTI 14.5-17 gear ratios revised DSG/STD.
T3 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.
T3 BRZ vs BRZ TS #32022wordingneutralT3 Spec Lines Subaru BRZ TS (13-21) added to class specification wording.
T3 Remove StopTech 4 piston BBK, allow any 4 Piston Kit - VW GTI #33082suspension & brakesneutralT3 VW GTI/Jetta GLI allows any 4-piston brake kit instead of StopTech only, max 355mm x 32mm.
T2 BMW Z4M Adjustment #31885weight -50 lbsfasterT2 BMW Z4M 06-08 weight reduced from 3150 to 3100 lbs.
STL Throttling Device Clarification #31323wordingneutralSTL and STU piston engines clarified: intake manifold and cylinder head porting remains free.
STL Mazda Renesis Restriction #31467inductionfasterSTL Mazda Renesis flat plate restrictor increases from 55mm to 60mm.
STL Clarification of 79-85 RX7 Spec line #31621wordingneutralSTL Mazda RX-7 12A 79-85 clarifies carburetor, emissions, and water jacket modification rules.
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.
T3 Request FRS/BRZ/86 T3 Weight Reduction #30818weight -75 lbsfasterT3 Scion FR-S/Toyota 86 GT and Subaru BRZ lose 75 lbs, to 2675 lbs minimum weight.
T3 Request to Classify 2022 Toyota 86 / Subaru in T3 & T4 #30931cars addedneutral2022+ Subaru BRZ and Toyota 86 newly classified in T3 at 2750 lbs with 245 max tires.
T3 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.
T3 Please Adjust Years Allowed for BMW 335i to 07-10, not 08-13 #31530wordingneutralT3 BMW 335i eligible model years narrowed from 08-13 to 07-10.
T3 Please Adjust Years Allowed for BMW 135i to 08-10, not 08-13 #31531wordingneutralT3 BMW 135i model years restricted from 08-13 to 08-10.
T3 Request to clarify radiator hoses #31682wordingneutralT2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted.
T3 T3 Nissan Z Suspension Update #31728wordingneutralT3 Nissan Z 350Z and 370Z suspension control arm options expanded from 'and' to 'or' for SPC parts.
T3 Clarify Permitted/Allowed #31743wordingneutralT2, T3, T4 clarify that spec lines listing permitted or allowed parts are alternatives to category rules, not replacements.
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.
T3 Request to correct model years BMW Z4 M Coupe #31371wordingneutralT3 BMW Z4 M Coupe model years corrected from 2007 to 06-08.
T3 Correct letter the 31327 #31563weight +150 lbsslowerT3 Subaru STI 15-20 weight increases 150 lbs, to 3350.
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.
T3 Request to Classify 2014 VW Jetta 1.8t TSI #30436cars addedneutralT4 Volkswagen Passat, Jetta 1.8T adds 2014 model year to eligible years.
T3 Request Weight Reduction 323is #30765weight -100 lbsfasterT3 BMW 323Ci/Is 98-00 minimum weight reduced from 3100 to 3000 lbs.
T3 Class Newer STI in T3 #31327cars addedneutralSubaru STI (15-20) newly classified in T3 at 3200 lbs minimum weight with 37mm turbo inlet restrictor required.
STL Request to clean up Spec MX-5 Redundancy #31069wordingneutralSTL Spec MX-5 removes redundant specification line; no performance change.
T2 BMW M2 CS Power Stick Part Number #31087wordingneutralT2 BMW M2 CS Cup 2020- must run Purple power stick, part #8324089 instead of #TBD.
T2 997.1 EO #30933wordingneutralT2 Porsche 911/997.1 (06-08) now allows alternate Cargraphics CARP97DFIFKR exhaust manifold.
T2 Request #30406weightfasterT2 BMW M2 CS Cup 2020- weight increases from 3625 to 3600 lbs; mandatory Purple power stick added.
T3 Follow-up to letter 29797-Porsche Spec Boxster in T3 Adjustment #30144weight -50 lbsfasterT3 Porsche Spec Boxster minimum weight reduced from 2600 to 2550 lbs.
T3 Wheel Size #30677tyres & wheelsfasterT3 Porsche Cayman 06-08 wheel size changes from 18x8 to 18x9 inches.
T3 Request weight adder to be applied to the Global Cup Miata ND2 #30730weightslowerT3 Mazda MX-5 Global Cup Miata ND2 with sequential gearbox allowed +100 lbs weight adder.
STL VW Engine Request #30625engineslowerSTL Volkswagen 2.0L TFSI 1984cc classified with turbocharger removal required, meeting all other STL specs.
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.
T3 Civic Type R Brake Rotors #29817weightslowerT3 Honda Civic Type-R 2020+ allows brake rotor 45251-TGH-A01 with 25 lb penalty.
STL Request Mazda B5 DOHC #30420cars addedneutralSTL Mazda B5 DOHC added to classification with standard STL regulations.
STL Honda B16A (JDM) Restrictor change #30531inductionslowerSTL Honda B16A JDM restrictor reduced from 54mm to 53mm.
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.
T3 Requesting Variance on Hardtop #30093wordingneutralT3 Porsche Boxster/Boxster S (00-04) now permits any OEM or aftermarket hardtop retaining OEM roof silhouette.
T3 07-09 and 10-13 Mazdaspeed 3 Fuel Pump #30154wordingneutralT3 Mazdaspeed3 07-09 and 10-13 now allow CorkSport Gen-6-999-10 or Autotech 10-127-100K fuel pumps.
STL ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wordingneutralST oil coolers and filters now explicitly allowed to be added or substituted; wording clarifies existing permissions.
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.
T3 Request consistency review in GCR #30263wordingslowerT2-T4 clutch disc and pressure plate must be at least 95% of factory OEM weight.
T3 Request to classify 2006-2008 Cayman #30315cars addedneutralPorsche Cayman 06-08 classified in T3 with 2687cc engine, 3050 lbs minimum weight, 18-inch wheels, 245 tires.
STL GM Ecotec engines in STL #30247wordingneutralSTL GM Ecotec engines now permit any combination within the family, must use 55mm flat plate restrictor.
STL Super Touring Alternate Miata Hubs #30345wordingneutralSTL/STU 90-05 Mazda Miata gains approval for Mazda Motorsports Development alternate front wheel hubs.
T2 Request BMW M2CS door glass removal #30254aerofasterT2 BMW M2 CS Cup 2020- permitted to remove door glass and mechanism.
T3 2020 T3 Suggested Changes #30002wording -50 lbsslowerT3 Ford Mustang EcoBoost gets 35mm TIR; Nissan 350Z DE Motor down 25 lbs to 3250; Mustang V6 down 50 lbs to 3475, restrictor tightened 55mm to 58mm.
STL Brake Component Relocation #29990wordingneutralST cars may relocate ABS actuation hardware and wiring anywhere in engine compartment.
STL Super Touring Wing Clarification #30111aeroneutralSTL rear wing trailing edge, including end plates and gurney flap, maximum rearward mounting clarified to center of rearmost bodywork.
STL Transmission Options #30118wordingneutralSTL allows OEM gear sets from same manufacturer transmissions with input shaft modifications for fitment.
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.
T3 2021 Toyota Supra #29567cars addedneutralToyota Supra 2020- newly classified in T2 at 3450 lbs minimum weight with 295 tire and 19-inch wheels.
T3 Chevrolet Camaro LT-I4 Turbo 1LE (2019-) Model Year to 2016- #30090tyres & wheelsfasterT3 Chevrolet Camaro LT-I4 Turbo 1LE reclassified to 2016- model year, max tire size 275, TIR required 35mm.
T3 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.
T3 Spec Boxster Tire Size #30159tyres & wheelsfasterT3 Spec Boxster tire size increased from 225 to 245 DOT, permitting wider tires.
STL Request for FWD and RWD Parity #29728weightfasterSTL RWD strut suspension weight penalty cut to 0.5%, other RWD cut to 2.5%.
STL Request to Remove Honda F20C 2% Weight Penalty #29815weightfasterSTL Honda F20C loses 2% weight penalty, minimum weight reduced by approximately 35 lbs.
STL Request for FWD and RWD Parity #30023inductionslowerSTL Honda B16/B17/B18C1 restrictor tightened to 53mm; B18C variants and Mazda MZR to 52mm.
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.
T3 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.
T3 Allow the SpecMX-5 Update Kit Into Touring 4 for the MX-5 #29681wordingunclearT3 and T4 Mazda MX-5 06-15 now allow Mazda Transmission kit part # 0000-02-5700.
T3 350Z Rear Caliper Replacement #29710wordingneutralT2 and T3 Nissan 350Z and 370Z permit 44011-RC350 rear caliper kit and SZ350 rotors.
T3 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.
T3 Cap year range on all 86s #29908wordingneutralT3 and T4 FR-S, 86, and BRZ year ranges capped: T3 at 2021, T4 at 2017-2021.
STL Request clarification on wing measurement #29640aeroneutralST aero devices and reference areas now include end plates but exclude fasteners protruding over 1/2 inch.
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.
T3 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.
T3 Request to Classify Honda Civic Type R in T3 #27840cars addedneutralHonda Civic Type R (2017-) classified in T3 at 3350 lbs with 1996cc engine, 245 max tire, 20-inch max wheel.
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.
STL Minimum Weight Determination #27695wordingneutralSTL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis adjustments.
STL ST Gurney flap Wicker clarification #29012wordingneutralSTL and STU rear wing rules clarify that wicker is a Gurney flap; no performance change.
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.
T3 Request to classify 2009 Honda Accord v6 manual #28913cars addedneutralT3 Honda Accord (2009) V6 manual classified: 3471cc, 3450 lbs, 245 max tire, 19-inch wheels.
STL 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.
T3 SADEV Sequential Gearbox #28763wordingneutralT3 Mazda MX-5 Global Cup Miata ND2 2016-2019 must meet all ND2 Global Cup rules without appendix reference.
T3 Request for competition adjustment for the MK5 GTI FSI engine #28802suspension & brakesfasterT3 VW GTI FSI gains turbo inlet restrictor allowance to 60mm, R32 brakes, Stoptech 4-piston kit, and Neuspeed intake options.
T3 Request to Add a Vehicle to the Roster (contd.) #27698cars addedunclearCannot read: letter references external document #27663 not provided.
STL Request to add 2016-2019 GMX-5 Spec line #28604cars addedneutralSTL adds 2016-2019 Mazda MX-5 Global Cup at 2000cc, 2450-2550 lbs minimum weight.
STL Request to update PN for MX-5 #28622wordingunclearSTL Mazda MX-5 Club Model 06-15 allows Mazda header part number 0000-06-5407-NC.
STL Correction - Clarification Honda/Acura B18B engine Letter # 26209 #28873inductionunclearSTL Honda/Acura B18 non-C gets 54mm restrictor; B18C variants drop B18C1, get 53mm restrictor.
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.
T3 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.
T3 Request Nissan 350Z Part Number change #28145enginefasterT3 Nissan 350Z Spec 2 DE Engine loses 57mm flat plate restrictor requirement.
STL STL Honda B18 restrictor changes #28794inductionfasterSTL Honda B18 restrictor reduced from 54mm to 53mm flat plate; B18C1 added with 54mm restrictor.
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.
T3 2015 + Ford EcoBoost Mustang Sway Bars #28398suspension & brakesneutralT3 Ford Mustang EcoBoost and V6 sway bars allowed up to 35mm front, 25mm rear.
T3 Z3M Roadster Weight #28437weightfasterT3 BMW Z3 M & Coupe 1998-1999 weight reduced from 3350 to 3150 lbs.
STL Change GM LNF 2.0 Allowance to LSJ Engine for Viable STL 2.0 #27884engineslowerSTU GM Ecotech LNF now allowed with turbo removed or with LE5 head and intake manifold, meeting STL specs.
STL Acura/Honda B18C engine chart. Reduce the current 54 mm flat plat #28663inductionslowerSTL Mazda MZR restrictor reduced from 54 mm to 53 mm.
STL Mazda MZR engine chart. Reduce the current 55 mm flat plate to 53 #28664inductionslowerSTL Mazda MZR restrictor reduced from 55 mm to 53 mm.
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.
STL Request to add wheel part numbers #28342wordingneutralSTL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL.
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.
T3 Clarify 05-10 V8 Mustang Spring Rates Wording/Adjust Restrictor #28238wordingneutralT3 05-10 V8 Mustang allowed parts clarified: strut tower brace, radiator, springs to 500 lbs/in front and 300 lbs/in rear, sway bars, damper kit.
T3 Correct Touring 3 05-10 Mustang final drive #28288wordingneutralT3 Ford Mustang Coupe GT & Shelby GT 4.6L 05-10 adds permitted final drive ratios: 3.31, 3.55 or 3.73.
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.
T3 2006 BMW E90 330i Sedan Classification #26663cars addedneutralBMW 330i 2006-2012 added to T3 with 2996cc engine, 3200 lbs minimum weight.
T3 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.
T3 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.
T3 Request for 2005 Subaru STI Changes #27658tyres & wheels +50 lbs
T3 Request to Classify 2017 Ford Fiesta ST #27700cars addedneutralT3 adds 2017 Ford Fiesta ST, 1596cc, 2600 lbs minimum weight, 245 max tire, 17x9 wheels.
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.
T3 Clarification of On-Board Fire System for T2 #27183wordingneutralT2 requires onboard fire system; T3 and T4 may have one per GCR 9.3.
T3 Mustang Ecoboost and GT Transmission #27439otherunclearT3 Ford Mustang EcoBoost 2015- gains three transmission gear ratio options.
T3 Nissan 350Z HR Engine Restrictor Plate/Minimum Weight #27442induction +50 lbsslowerT3 Nissan 350Z and 370Z HR engines: restrictor plate enlarged from 37mm to 42mm, weight increased 50-100 lbs.
T3 Request help for the GMX5 #27572tyres & wheelsneutralT3 Mazda MX-5 Global Cup Miata (2016-) tires now 215/610 R17 BF Goodrich G-Force Slick or wet; removes touring tire requirement.
T3 Request for 05-10 Mustang GT Suspension Upgrades #27777suspension & brakesfasterT3 05-10 Mustang GT 4.6L suspension upgrades allowed: tower braces, radiator, 500/300 lbs/in springs, sway bars, dampers, control arms, shocks, driveshaft.
T3 Please Update the BMW SpecE46 Rules #27781wordingneutralT3 BMW SpecE46 updates to SpecE46 rules Version 2.6 to 2.7, tire width to 225 maximum.
T3 Request for 02-03 WRX Spec Line Parts #27864weight -100 lbsfasterT3 Subaru WRX 02-05 minimum weight drops 100 lbs to 3250.
T3 T4 RX8 Classification Error #27902wordingneutralMazda RX-8 Base/R3 (04-12) reclassified in T3 and T4 to include Sport and GT variants.
T3 Request to add Toyota 86 GT to Spec Line #27910cars addedneutralToyota 86 GT (2017-) added to T3 and T4 Spec Line.
T3 Request to add 2018 Subaru BRZ in T3 #27253cars addedneutralT3 Scion FR-S/Toyota 86 and Subaru BRZ year range extended from 13-17 to 13-20.
STL Request to Classify Spec MX-5 Challenge in STL #27399cars addedneutralMazda Spec MX-5 Challenge classified in STL with 2000cc displacement and 2500 lbs minimum weight.
T3 Request Mazda NC MX-5 alternate transmission gear ratios #27155wordingneutralT3 Mazda NC MX-5 gains two alternate six-speed and one five-speed transmission gear ratio option.
T2 Request spare tire/wheel clarification #27012wordingneutralT2-T4 spare tire/wheel rules clarified: removable covers can be removed with hardware and bracketry.
T3 Request spare tire/wheel clarification #27012wordingneutralT2-T4 spare tire/wheel rules clarified: removable covers can be removed with hardware and bracketry.
T3 Request guidance for 2014-2017 MK7 Volkswagen GTI #26866wordingneutralT3 Mk7 GTI gains R32 brake package, 4-piston Stoptech kit to 355mm, and ECS street shield allowance.
STL Request clarification for manifold and throttle in STU #27004inductionfasterSTU alternate intake manifolds now allowed case-by-case instead of prohibited.
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.
T3 Request BMW e36 M3 sway bar and links #26885suspension & brakesneutralT3 BMW E36 M3 96-00 allows alternate sway bars, 35mm front and 27mm rear.
STL Request Restrictor Plate correction #26779inductionfasterSTL Acura/Honda B18 except C engine restrictor increases from 53mm to 54mm flat plate.
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.
T3 Request to properly class base Porsche Cayman #26276cars addedneutral09-12 Porsche Cayman newly classified in T3 at 3150 lbs with 2900cc engine.
STL Request Ride Height Clarification #26597wordingneutralSTL and STU ride height measurement clarified: without driver, at rocker panel lowest point, excluding pinch weld.
T3 Request to classify a 2019 Chevrolet Camaro LT-I4 Turbo 1LE #25731cars addedneutralT3 Chevrolet Camaro LT-I4 Turbo 1LE (2019-) classified with 1998 cc engine, 3450 lbs minimum weight, 245 max tire size.
T3 T3 Civic Si weight change #26294weightfasterT3 Honda Civic Si 2017- minimum weight reduced 100 lbs, to 2900.
T3 Class Civic Si 2017+ w/ alternate cage #26449cars addedneutralHonda Civic Si 2017+ with alternate cage classified in T3 at 3075 lbs minimum weight.
T3 Classify 2014-2017 MK7 Volkswagen GTI for T3 #26695cars addedneutralT3 classifies 2014-2017 Volkswagen GTI with 35 mm turbo inlet restrictor, 3080 lbs DSG, 3050 lbs standard.
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.
T3 Request to allow E36 M3 in T3 prepared to BMWCCA I sport #25195cars addedneutralBMW E36 M3 (96-00) BMWCCA I Sport newly classified in T3 at 3100 lbs minimum weight.
STL Request to reduce weight of RX8 with Renesis rotary #25781weight -100 lbsfasterSTL Mazda Renesis minimum weight reduced from 2800 to 2700 lbs.
STL Request for Open Brake Pads On Mazda MX-5 Cup NC #25821wordingneutralSTL Mazda MX-5 Cup brake pad compound changed to open.
STL Request to clarify B18C1 GSR Honda B motor table #26209cars addedneutralSTL adds Acura/Honda B18C1 GSR with 54mm flat plate restrictor and port matching limited to 1 inch.
STL Port Matching #26415wordingfasterSTL Mazda 12 and 13B now permit port matching; previous ban removed.
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.
T3 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.
T3 Classify 2015+ WRX #25832cars addedneutralT3 Subaru WRX (2015-) classified at 3275 lbs with 35mm turbo inlet restrictor required.
T3 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.
T3 Request to allow T3 06-15 Miata 17x8 wheels #26161tyres & wheelsfasterT3 Mazda MX-5 NC 06-15 wheel width increases from 17x7 to 17x8.
T3 Request T3 06-15 Miata header #26162aerofasterT3 Mazda MX-5 NC 06-15 now allows any aftermarket header.
T3 Request Pontiac GXP same allowances to Saturn Sky #26175aerofasterT3 Saturn Sky intercooler tolerance increases from 32mm to 35mm TIR; new calipers and springs permitted.
T3 Consider opening class rules to allow any thermostat #26187wordingneutralT2, T3, T4 now allow any thermostat serving only OE intent, previously restricted.
T3 2005-2009 Legacy GT/Spec B #26384cars addedneutralT3 Subaru Legacy GT/Spec B 05-09 newly classified with 2457cc, 18×9 wheels, 245 tires, 3300 lbs.
T3 Cap 2016 Mazda Miata year at 2018 #26388wordingneutralT3 and T4 Mazda MX-5 Miata eligibility capped at 2018 model year, effective 2019-03-01.
T3 Request correction on brake sizes #26170wordingneutralT3 Mazda Mazdaspeed3 07-09 front brake disc increases to 320mm vented, rear to 300mm solid.
STL Request to equalize FPR Reduction on all B-Series Vtec Engines #24746inductionslowerSTL B18C Type R variants get 54mm flat plate restrictor; B17 also gets 54mm restrictor.
STL Request E&O for Mazda Miata Spec Line #25955wordingunclearSTL Mazda Miata removes maximum displacement limit and adjusts minimum weight.
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.
T3 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.
T3 Request to update SpecE46 Appendix N. with 2019 Rules #25722wordingneutralT3 BMW SpecE46 rules reference updated from Appendix N to Version 2.6 Effective Jan 1, 2019.
T3 Request Alternative Nissan Brake Parts - 350Z #25747suspension & brakesneutralT3 Nissan 350Z Track/Touring/Standard/Nismo 03-08 permitted to use Nissan brake kit part number 41000-BRKIT.
T3 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.
T3 Clarify Subframe Bushings Permitted for T2-T4 #25800wordingneutralT2-T4 subframe bushings may now be replaced with non-spherical bushings of any material.
T3 Additional weight adjustments for T3 cars T3 weight loss #25803weightfasterT3 field loses 50 lbs across 27 cars including Acura TL, BMW 335i, Camaro, Mustang, Miata, RX-8, 370Z, WRX.
T3 Request for Alternate EcoBoost Mustang Brakes #25813suspension & brakesslowerT3 Ford Mustang EcoBoost gains Ford Motorsports or Brembo brake kit options, +100 lb.
T3 Request to Add the FR-S/86 and BRZ Spec Lines to T3 #25888weightfasterT3 FR-S/86 and BRZ: wheels to 17x9, tires to 255, weight to 2750 lbs.
T3 Request to Clarify BMW SpecE46 Tire Verbiage #26027tyres & wheelsneutralT3 BMW SpecE46 now permits any DOT tire up to 225 width as alternate to spec tire.
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 STL" is the class's best as a share of STL'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 STL'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.