T1 vs FE2 vs B-Spec pace at Buttonwillow Raceway Park
Quickest here:T1 1:46.465 Ian Barberi, Cal Club 2025 qualifying · FE2 1:39.265 Jon McClintock, Cal Club 2026 qualifying · B-Spec 2:09.353 Trenton Kramer, Cal Club 2026 qualifying
T1FE2B-Specsolid race · dashed qualifying · slower is lower
T1FE2B-Specsolid race · dashed qualifying · each class's best lap as a share of T1's at the same event (the reference class, changeable above); 100% is level, higher is quicker
Event
T1
FE2
B-Spec
Qual best
Race best
Trap
Qual best
Race best
Trap
vs T1
% of T1
Qual best
Race best
Trap
vs T1
% of T1
Cal Club 2026 CALCL262026-02-21
1:59.760Ed Gless · only car+13.295s (+12.49%)
1:59.123Ed Gless · only car+11.689s (+10.88%)
120.7Ed Gless-18.6 mph (-13.3%)
1:39.265Jon McClintock · fastest of 3 · top 3 within 1.5s-0.093s (-0.09%)
1:40.253Jon McClintock · fastest of 3 · top 3 within 2.2s+0.541s (+0.54%)
156.6Paul Marino+29.4 mph (+23.1%)
-18.870squal -20.495s
84.2%qual 82.9%
2:09.353Trenton Kramer · fastest of 5 · top 5 within 6.1s-1.160s (-0.89%)
2:09.916Trenton Kramer · fastest of 5 · top 5 within 2.7s-0.138s (-0.11%)
121.5Trenton Kramer+23.3 mph (+23.8%)
+10.793squal +9.593s
109.1%qual 108.0%
39 rule changes (T1: 13, FE2: 2, B-Spec: 24)8 weight · 4 cars added · 3 induction · 2 suspension & brakes · 1 removed · 1 tyres & wheels · 19 wording · 1 other · C-Spec rear sway bars approved for Chevrolet Cruze, Dodge Dart, Ford Focus, Honda Civic, Mazda3i, Toyota Corolla with specified part numbers. · T1 Corvette C6 LS1/LS6 Spec Line reinstated: 3200 lbs minimum weight, 70mm restrictor required. · B-Spec Chevrolet Sonic and Ford Fiesta, Honda Fit notes reorganized from individual allowances to approved parts lists; wording cleanup. · B-Spec: Sonic restrictors removed, Fit MT +25 lbs to 2550, Fit CVT restrictor removed, Mini Coopers restrictors increased 2-4 mm, Versa sedans -25 lbs to 2425, Versa/IA restrictors removed. · B-Spec Mazda2 10-14 cat-delete header swap removes 50 lb weight adder option, now Mazda Motorsports PN only. · T1 Spec Line restrictor changes from 70mm flat plate to unspecified new specification. · Unable to summarize: letter states intent but provides no actual rule changes to S2000 specification. · T1 non-GT4 cars: multiple restrictors enlarged (70mm to 73mm, 75mm to 78mm, 55mm to 60mm, 61mm to 70mm); one weight increased to 3600. · T1 BMW M3 E92 (08-13) Spec Line 1090 removed entirely. · B-Spec Honda Fit MT 07-08 allows Torque Solution Shifter Cable Bushing kit TS-SCB-506. · B-Spec Ford Fiesta Hatchback and Sedan gain 55 lbs to 2525; restrictors increase 1 mm. · B-Spec Hyundai Accent and Kia Rio remove Bilstein B8 shock 33-187112 rear suspension approval. · B-Spec Honda Fit MT (07-08) becomes Runoffs-eligible; previous three-weekend Super Tour requirement removed. · FE and FE2 Enterprises must use bubble tail P/N WM138014; FE2 allows only this configuration. · B-Spec and C-Spec: asterisk removed from public road usage note in rule 9.1.10.D.9. · B-Spec Honda Fit MT 09-14 two pedal shutdown may be disabled by cutting/de-pinning pin 42 BKSW at main ECU connector. · B-Spec Honda Fit MT 07-08 intake restricted to Injen SP1511 only, from any Cold Air Intake Package. · B-Spec adds Hyundai Accent Sedan (12-17) and Kia Rio Sedan (12-17), both 1591cc, 2525 lbs, 40mm FPR restrictor. · B-Spec Honda Fit MT 09-14 allows Acuity Shifter Base Bushing Kit 1954. · B-Spec Honda Fit AT 09-14 adds Weapon R Intake 301-166-301 to approved parts. · B-Spec and C-Spec shift linkage/cables no longer prohibited from any modification; approved aftermarket bushings now permitted. · B-Spec Hyundai Accent Hatchback and Kia Rio Hatchback model year ranges corrected. · B-Spec 07-08 Honda Fit MT minimum weight increases 50 lbs, to 2450. · Honda Fit 07-08 MT and AT approved for Bilstein B14 kit 47172401 in B-Spec. · Porsche 981 GT4 Clubsport added to T1 as spec line 4085, minimum weight 3100 lbs with driver. · T1 Honda S2000 minimum weight reduced from 2950 lbs to 2900 lbs. · T1 BMW E46 M3 permits BMW #GS7D36SG aftermarket sequential transmission in SL# 1060 and 1070. · T1 BMW M3 E92 minimum weight reduced to 3300 lbs. · T1 Mustang Darkhorse R gets 315 front and rear tyres, loses 500 lbs minimum weight to 3600. · B-Spec Honda Fit MT intake now limited to three models with 25lb adder; Mazda2 exhaust headers allowed with up to 50lb adder; Mini Coopers FPR increased 1-2 points; Nissan Versa sedans 40lbs lighter, Yaris models 50lbs lighter. · B-Spec Hyundai Accent and Toyota Yaris weight adjustments: ±25 lbs based on rear brake type. · B-Spec Hyundai Accent and Kia Rio (12-19) allow Bilstein B14 kit #47167490 front shocks and BabyFace Fabrication sump extension #BF-HYU-PAN. · FE2 allows driver safety and comfort modifications for disabled drivers with SCCA approval, not transferable to other drivers. · Cadillac CT4-V Blackwing added to T1 Spec Line 1115, 3564cc, 3750 lbs minimum weight. · B-Spec Toyota Yaris Hatchback 12-18 rear brakes now allow 10.2 inch disc alternative to 7.9 drum. · B-Spec Toyota Yaris Hatchback and Sedan may now disconnect speed sensor. · B-Spec Fiat 500 (12-17) spec line expires 1/1/26 unless appeal filed. · T1 Mustang Spec 1430 restrictor opens 60mm to 65mm; Spec 1460 weight rises to 3500 lbs, restrictor 70mm; Corvette 1190 restrictor opens 67mm to 70mm; BMW 1090 restrictor narrows 40mm to 35mm; BMW 1100 weight rises to 3350 lbs.showhide
B-Spec C-Spec Rear Sway Bars #39652wordingneutralC-Spec rear sway bars approved for Chevrolet Cruze, Dodge Dart, Ford Focus, Honda Civic, Mazda3i, Toyota Corolla with specified part numbers.
T1 LS1 into Corvette C6 Spec Line Request #39716cars addedneutralT1 Corvette C6 LS1/LS6 Spec Line reinstated: 3200 lbs minimum weight, 70mm restrictor required.
B-Spec Notes section cleanup #39062wordingneutralB-Spec Chevrolet Sonic and Ford Fiesta, Honda Fit notes reorganized from individual allowances to approved parts lists; wording cleanup.
B-Spec 2026 BOP Recommendations #39475other +25 lbsunclearB-Spec: Sonic restrictors removed, Fit MT +25 lbs to 2550, Fit CVT restrictor removed, Mini Coopers restrictors increased 2-4 mm, Versa sedans -25 lbs to 2425, Versa/IA restrictors removed.
T1 additional T1 adjustment #39520inductionunclearT1 Spec Line restrictor changes from 70mm flat plate to unspecified new specification.
T1 Keep S2000 Classification #39344wordingunclearUnable to summarize: letter states intent but provides no actual rule changes to S2000 specification.
T1 Correcting and updating T1 GT4 spec lines #39394weight
T1 BOP adjustments to non GT4 T1 cars #39406induction +100 lbsfasterT1 non-GT4 cars: multiple restrictors enlarged (70mm to 73mm, 75mm to 78mm, 55mm to 60mm, 61mm to 70mm); one weight increased to 3600.
T1 Remove T1 Spec Line #39407removedneutralT1 BMW M3 E92 (08-13) Spec Line 1090 removed entirely.
B-Spec Alternate Shift Cable Bushings and Rear Spring Seats #38472wordingneutralB-Spec Honda Fit MT 07-08 allows Torque Solution Shifter Cable Bushing kit TS-SCB-506.
B-Spec Fiesta BOP Adjustment #38847weight +55 lbsslowerB-Spec Ford Fiesta Hatchback and Sedan gain 55 lbs to 2525; restrictors increase 1 mm.
B-Spec Request to Remove Rear Shock From Spec Line Hyundai Accents/Kia #39017suspension & brakesunclearB-Spec Hyundai Accent and Kia Rio remove Bilstein B8 shock 33-187112 rear suspension approval.
B-Spec Update Honda Fit MT (07-08) Runoffs Eligibility #39060wordingfasterB-Spec Honda Fit MT (07-08) becomes Runoffs-eligible; previous three-weekend Super Tour requirement removed.
FE2 FE & FE2 Bubble Tail #38978wordingneutralFE and FE2 Enterprises must use bubble tail P/N WM138014; FE2 allows only this configuration.
B-Spec Remove Asterisk from Rule 9 #38768wordingneutralB-Spec and C-Spec: asterisk removed from public road usage note in rule 9.1.10.D.9.
B-Spec Disabling 2 Pedal Shutdown #38354wordingneutralB-Spec Honda Fit MT 09-14 two pedal shutdown may be disabled by cutting/de-pinning pin 42 BKSW at main ECU connector.
B-Spec Update Honda Fit MT (07-08) Intake Allowance #38530inductionslowerB-Spec Honda Fit MT 07-08 intake restricted to Injen SP1511 only, from any Cold Air Intake Package.
B-Spec Add Sedan spec lines for Hyundai & Kia #37537cars addedneutralB-Spec adds Hyundai Accent Sedan (12-17) and Kia Rio Sedan (12-17), both 1591cc, 2525 lbs, 40mm FPR restrictor.
B-Spec Shifter Bushing Questions. #38048wordingneutralB-Spec Honda Fit MT 09-14 allows Acuity Shifter Base Bushing Kit 1954.
B-Spec Add Weapon R Intake to Honda Fit MT (09-14) Spec Line #38306wordingneutralB-Spec Honda Fit AT 09-14 adds Weapon R Intake 301-166-301 to approved parts.
B-Spec Update Rule 46 #38307wordingneutralB-Spec and C-Spec shift linkage/cables no longer prohibited from any modification; approved aftermarket bushings now permitted.
B-Spec Correct Hyundai/Kia Model Years #37943wordingneutralB-Spec Hyundai Accent Hatchback and Kia Rio Hatchback model year ranges corrected.
B-Spec 07-08 Honda Fit MT Requests #37974weight +50 lbsslowerB-Spec 07-08 Honda Fit MT minimum weight increases 50 lbs, to 2450.
B-Spec Add B14 Kit Part # to Honda Fit (07-08) Spec line #38010wordingneutralHonda Fit 07-08 MT and AT approved for Bilstein B14 kit 47172401 in B-Spec.
T1 Acceptance of Porsche 981 GT4 Clubsport into T1 #36664cars addedneutralPorsche 981 GT4 Clubsport added to T1 as spec line 4085, minimum weight 3100 lbs with driver.
T1 Request to Restore T1 Honda S2000 to Proper Weights #37644weight -50 lbsfasterT1 Honda S2000 minimum weight reduced from 2950 lbs to 2900 lbs.
T1 DCT Transmission in E46 #37964wordingneutralT1 BMW E46 M3 permits BMW #GS7D36SG aftermarket sequential transmission in SL# 1060 and 1070.
T1 Reduce E92 M3 Minimum Weight to 3050 #38092weightfasterT1 BMW M3 E92 minimum weight reduced to 3300 lbs.
T1 Finalize Spec Line for T1 Darkhorse #38106tyres & wheelsfasterT1 Mustang Darkhorse R gets 315 front and rear tyres, loses 500 lbs minimum weight to 3600.
B-Spec 2025 BOP Recommendations #37520weightfasterB-Spec Honda Fit MT intake now limited to three models with 25lb adder; Mazda2 exhaust headers allowed with up to 50lb adder; Mini Coopers FPR increased 1-2 points; Nissan Versa sedans 40lbs lighter, Yaris models 50lbs lighter.
B-Spec Hyundai/Toyota Factory Rear Disc Models #37534wordingneutralB-Spec Hyundai Accent and Toyota Yaris weight adjustments: ±25 lbs based on rear brake type.
B-Spec Request to Update the Spec line for Hyundai Accent and Kia Rio #37880wordingneutralB-Spec Hyundai Accent and Kia Rio (12-19) allow Bilstein B14 kit #47167490 front shocks and BabyFace Fabrication sump extension #BF-HYU-PAN.
FE2 Driver Safety & Comfort #37965wordingneutralFE2 allows driver safety and comfort modifications for disabled drivers with SCCA approval, not transferable to other drivers.
T1 Cadillac CT4-V Blackwing #38003cars addedneutralCadillac CT4-V Blackwing added to T1 Spec Line 1115, 3564cc, 3750 lbs minimum weight.
B-Spec Toyota Yaris Hatchback (12-18) rear disc brakes #37530suspension & brakesneutralB-Spec Toyota Yaris Hatchback 12-18 rear brakes now allow 10.2 inch disc alternative to 7.9 drum.
B-Spec Yaris Speed Sensor #37536wordingneutralB-Spec Toyota Yaris Hatchback and Sedan may now disconnect speed sensor.
B-Spec Set Expiration Date For Fiat 500 #37689wordingneutralB-Spec Fiat 500 (12-17) spec line expires 1/1/26 unless appeal filed.
T1 Correct and make new T1 BOP adjustments. #37737weight +75 lbsunclearT1 Mustang Spec 1430 restrictor opens 60mm to 65mm; Spec 1460 weight rises to 3500 lbs, restrictor 70mm; Corvette 1190 restrictor opens 67mm to 70mm; BMW 1090 restrictor narrows 40mm to 35mm; BMW 1100 weight rises to 3350 lbs.
Cal Club 2025 CALCL252025-02-22
1:46.465Ian Barberi · fastest of 2
1:47.434Ian Barberi · fastest of 3 · top 3 within 11.8s
139.3Drew Delmonico
1:39.358Paul Marino · fastest of 4 · top 4 within 1.5s
1:39.712Paul Marino · fastest of 4 · top 4 within 1.7s
127.2Tom Hope
-7.722squal -7.107s
92.8%qual 93.3%
2:10.513Joseph Gersch · fastest of 4 · top 4 within 6.8s
2:10.054Thomas Lepper · fastest of 4 · top 4 within 7.4s
98.1Ali Naimi
+22.620squal +24.048s
121.1%qual 122.6%
222 earlier rule changes on record, in force before Cal Club 2025 (from 2019)40 cars added · 31 weight · 20 induction · 19 suspension & brakes · 15 tyres & wheels · 6 engine · 4 aero · 3 removed · 78 wording · 6 other · B-Spec Honda Fit AT, Fit CVT, Mazda2, Mini Cooper R50 MT and CVT, Toyota Yaris remove redundant notes language. · B-Spec removes Mini Cooper Countryman R60, Cooper Paceman R61, and two Nissan Versa generations effective 2/1/25. · B-Spec Nissan Micra Cup Car spec line expires 7/1/25 unless appeal submitted by 6/30/25. · T1 Mustang gains 125 lbs to 3600, restrictor shrinks 65mm to 60mm. Corvette gains 50 lbs to 3500, restrictor shrinks 70mm to 67mm. BMW deleted. · T1 E46 M3 Spec Line 1050 allows VAC Motorsports throttle body VAC-TB-S54 on 3.250L engine instead of Dinan. · T1 Chevrolet Corvette C8 (2023-23) minimum weight reduced from 3600 lbs to 3500 lbs. · T1 Chevrolet Camaro Gen 5 restrictor increases from 75mm to 80mm flat plate. · T1 Audi R8 GT4 Spec Line #4020 maximum tyre size changes to 315 DOT, 305/645, or 30/65-18 (f), 33/68-18 (r) Non-DOT. · B-Spec and C-Spec cars replace wheelbase spec with induction restrictor (mm) values, effective 2025-01-01. · B-Spec Hyundai Accent and Kia Rio approve Bilstein B8 shock 33-187112 for rear suspension use. · T1 GT4 tire sizes adjusted across ten cars: most non-DOT rear to 305/660, Audi and McLaren 305/645, Camaro and Mustang 305/680. · BMW M4 GT4 (G82) added to T1 GT4 at 3525 lbs minimum weight with Red power stick control. · T1 Spec Lines now permits 5.5 inch clutch in Engine Notes. · T1 GT4 Spec Line 4020 restrictor opens from 44mm to 45mm, minimum weight drops to 3400 lbs. · Mustang Darkhorse R added to T1 homologated cars at 3,250 lbs minimum with 305/315 tires, ineligible for Runoffs until 3 Super Tour events. · T1 Corvette may roll or flatten wheel opening lips for tire clearance; plastic fenders may remove lips if edge thickness matches basic material. · T1 E46 M3 S54 can now use Dinan Throttle Body #D760-3400 on 3.250L engine. · B-Spec Toyota/Scion IA Sedan 16-20 allows ST Suspension Kit 13275022, requires three Super Tour weekends and OBD-II data submission. · Honda Fit AT 07-08 B-Spec and C-Spec: rear sway bar Progress #62.1060 and any cold air intake package now allowed. · B-Spec and C-Spec restricted to Goodyear Eagle RS/RS-R P205/50R15 and 225/45R17 tires respectively; Hankook tires removed; wet/dry mixing prohibited. · B-Spec Sonic restrictors increased to 5-6mm, Fit weight cut 50-25 lbs, Mini Cooper weight reduced 45 lbs, various restrictor adjustments. · B-Spec and C-Spec hood pins change from optional to recommended; factory release cable may be removed if pins used. · B-Spec and C-Spec Chevrolet Sonic and Cruze allow Babyface Fabrication brake caliper pistons. · B-Spec Honda Fit MT & CVT 15-19: cleaned up allowed parts notes, CVT gains Setrab transmission cooler option. · B-Spec Nissan Versa (09-11) spec line expires 1/1/2025 unless appeal filed by 12/1/2024. · B-Spec deletes redundant rule 25 in GCR Section 9.1.10.E. · B-Spec Hyundai Accent rear brakes corrected to 10.3 disc; Kia Rio rear brakes corrected to 10.3 disc. · B-Spec and C-Spec Chevrolet Sonic Bilstein B14 kit #47-171725 verified compatible, suspension wording clarified. · B-Spec Mazda2 and multiple Mini Cooper models eliminate redundant sway bar end link part number notes. · B-Spec Fiat 500 spec line changes from model year 2012–15 to 2012–17. · B-Spec Honda Fit 15-19 CVT weight increases to 2550 lbs, restrictor to 31mm. · B-Spec model descriptions standardized: trim levels and door count designations removed or replaced with body style wording. · B-Spec and C-Spec wheels must be same thickness spacers all four corners; wording clarified on offset and protrusion rules. · Mercedes AMG-C63 S (2023) classified in T1 with 4000 lbs minimum weight and 3700 restrictor. · B-Spec Honda Fit MT 2015-19 restrictor increases 30mm to 31mm, weight rises 2525 to 2550 lbs. · B-Spec and C-Spec now permit wheels of any offset if tire doesn't protrude beyond fender; spacers allowed with differing left-right offsets per axle. · B-Spec Mini Cooper Countryman R60, Paceman R61, and Nissan Versa 1797cc spec lines expire 1/1/2025 unless appealed by 12/1/2024. · T1 Honda S2000 classified with 2400 lb minimum weight, 2950 cc displacement, 4.75" supercharger pulley. · B-Spec Honda Fit 07-08 loses 125 lbs to 2400; Versa S 2020+ loses 150 lbs to 2550; Yaris iA 16-20 loses 250 lbs to 2450. · B-Spec Honda Fit 07-08 rear sway bar part number changed to Progress #62.1060. · Pontiac GTO 2006-2009 LS1 added to T1 as Spec Line 1590, 5700 cc, 3400 lbs minimum. · B-Spec and C-Spec eliminate case-by-case auxiliary transmission cooler approval requirement. · B-Spec Chevrolet Sonic 5dr Hatch MT allows aluminum radiator #ZZP-ZZ013. · B-Spec Honda Fit MT (09-14) and AT now split into separate spec lines with distinct allowances. · B-Spec Mazda 2 10-14 weight increases 70 lbs to 2350, cat-delete headers now permitted. · B-Spec Nissan Versa and Versa Note 2013-2019 now permit Hardrace HR-Q0146 19mm rear sway bar. · C8 Corvette T1 restrictor plate increases from 70mm to 72mm flat plate. · T1 NEW class removes 23 spec lines including Acura NSX, Ferrari, Porsche 996, Nissan Z cars, and others; Porsche 997 spec line 1680 expiration removed. · B-Spec allows Hankook tires at regionals only through 6-30-2024; Goodyear only from 7-1-2024 for all events. · B-Spec Nissan Versa Note Hatchback (2013) minimum weight drops 60 lbs to 2490. · B-Spec and C-Spec ECU and data acquisition rules clarified: ECU must be unaltered OE, no device capable of altering ECU characteristics permitted; data acquisition expanded to allow tachometer, air-fuel ratio, cylinder head temperature sen… · T1-GT4 batch adjustments: five cars lighter, two heavier, restrictors and ECU maps changed, five models now eligible for Runoffs. · T1 spec lines 1000, 1010, 1020, 1040, 1360, 1400–1410, 1520–1680, 1700–1720 deleted entirely. · C-Spec Mazda 3i 10-13 third gear ratio corrected from 3.84 to 1.84. · C-Spec Dodge Dart 14-16 bore x stroke corrected to 88.0 x 82.0 mm, displacement to 1998 cc. · T1 Chevrolet Corvette C5 LS2 added with 6000cc displacement, 3300 lbs minimum weight, 72mm flat plate restrictor. · T1 Chevrolet Corvette C7 (14-19) including Z51, Grandsport newly classified as homologated car. · T1 Gen 5 Camaro minimum weight drops 75 lbs to 3475; restrictor increases 70mm to 75mm. · T1 Aston Martin Vantage permitted to use OEM Sportshift II transmission. · Pontiac GTO 2006-2009 re-integrated into T1 with LS2 at 3400 lbs, 72mm restrictor, and LS3 at 3500 lbs, 61mm restrictor. · T1 Porsche 997-1 GT3 Cup added at spec line 4210, minimum weight 3050 lbs. · B-Spec adds Goodyear Eagle RS dry and wet tires as options alongside Hankook; Hankook restricted to regional events from 2024. · C-Spec adds Chevrolet Cruze, Ford Focus, Honda Civic, Mazda 3i, Toyota Corolla, VW Jetta; updates Dodge Dart, Mazda3s, Toyota Corolla specs. · Chevrolet Camaro GT4-R classified in T1 GT4 Spec Line 4035, minimum weight 3375 lbs, 315 max tire, 63mm restrictor, ineligible for Runoffs. · T1 Dodge Viper ACR / SRT RT-10 and ACR/ACR-X spec lines 1350 and 1370 remove 12/23 expiration. · T1 GT4 McLaren 570S, Mercedes AMG GT4, and Porsche 718 Cayman GT4 CS MR now eligible for Runoffs competition. · T1 GT4 BMW M4 Spec Line Number changed from 4050 to 4030. · T1 Corvette C5 gains approved aero parts: carbon rear spoiler, vented front splitter, side skirts, with 50 lb weight reduction allowed. · B-Spec Hyundai Accent GS Hatchback restrictor plate increases from 39mm to 41mm. · B-Spec Hyundai Accent GS Hatchback model years corrected from 13–19 to 12–19. · T1 Dodge Viper ACR/ACR-X restrictor increases from 50mm to 60mm flat plate. · T1 Dodge Viper ACR/ACR-X: Spec Line 1370 restrictor increases to 55mm, Line 1390 decreases to 55mm. · T1 Ford Mustang S197 05-14 now requires OEM 8.8 differential housing. · T1 Chevrolet Camaro Gen 5 LS7 gets two spec lines: 1131 with 70mm restrictor, 1136 with 53mm restrictor, both 3450 lbs minimum. · T1 Chevrolet Camaro Gen 5, Corvette C5 and C6: engine resleeve restricted to stock parameters only, no longer LS3 bore/stroke. · B-Spec adds Hankook 200/580R15 Z217 tire option alongside 205/50R15 C51; C-Spec specifies 225/45R17. · B-Spec and C-Spec Chevrolet Sonic allows ZZP aluminum radiator #ZZP-ZZ013; Hatch MT restrictor increases to 34mm. · B-Spec and C-Spec bumper caps now allow positive fasteners like machine screws and T-nuts or rivet-nuts; self-drilling and sheet metal screws prohibited. · B-Spec and C-Spec allow CAN bus connections to data systems for monitoring only; systems must not send data. · B-Spec Ford Fiesta 5dr and 4dr lose 25 lbs each, to 2470 lbs minimum weight. · B-Spec Ford Fiesta 5dr and 4dr lose 25 lbs each to 2470; Honda Fit MT and CVT lose 50 lbs each to 2525; Mazda2 loses 50 lbs to 2280; Kia Rio restrictor increases from 39 to 41 mm; Mini Cooper variants gain 75 lbs to 2675 with larger restri… · C-Spec Mazda 3i Touring 2.0 Skyactive MT (12-13) newly classified with 155 hp, 148 lb-ft torque, 2900 lbs. · B-Spec minimum ride height set to 6 inches, C-Spec to 5½ inches. · B-Spec springs capped at 500# front and rear; C-Spec at 600# front, 800# rear; both may be strapped to body. · B-Spec wheels minimum weight set to 13 lbs, C-Spec to 17 lbs. · B-Spec and C-Spec allow metal threaded inserts in plastic intake manifolds for throttle body fasteners. · T1 Ford Mustang S197 (05-14) reinstated with 3550 lbs minimum weight, 75mm restrictor, Voodoo engine permitted. · B-Spec and C-Spec wording clarified: CATEGORY to CATEGORIES, rules priority clarified for tire sizes, rim widths, springs, anti-roll bars, performance equipment. · T1 GT4 weights clarified for nine cars, ranging from 3200 lbs Porsche 718 Cayman to 3575 lbs Aston Martin. · T1-GT4 McLaren 570S and Mercedes AMG GT4 front tires widen to 315 mm. · T1 Chevrolet Camaro Gen5 LS3-6160 adds 70mm flat plate restrictor, weight 3550 lbs. · B-Spec Mini Cooper R56 MT/AT and Clubman R55 fuel pressure regulator increased from 40mm to 41mm with OE catalyst. · B-Spec may use helper springs up to 500 pounds rate; tender springs now prohibited. · T1 cars with aftermarket sequential transmissions get 10-inch max bellhousing; non-sequential cars gain 100 lbs weight break. · T1 GT4 all nine cars lose 125 lbs minimum weight with driver, from 3200–3575 to 3075–3450. · T1 removes GCR Section 9.1.9.1.A. and T1 Spec Lines entirely, sunsetting pre-2023 Touring 1 rules. · B-Spec Honda Fit 09-14 Automatic now allows aftermarket exhaust/header; Manual unchanged. · GT4 McLaren 570S maximum tire size changes to 285 front, 315 rear. · B-Spec Chevrolet Sonic and Honda Fit and Mini Cooper split into separate manual and automatic spec lines with distinct transmission ratios and final drives. · B-Spec tire rule adds Hankook 200/580R15 Z217 as alternative to 205/50R15 C51; no mixing wet and dry. · Eight GT4 models added to T1 with weights from 3200 to 3575 lbs and restricted power per SRO 2022 rules. · B-Spec Honda Fit 15-19 weight drops 225 lbs to 2575 lbs. · B-Spec Mazda2 10-14 rear sway bar now allows part 0000-04-2203-RR or 0000-04-2312. · T1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird, Pontiac GTO 6162 OEM minimum weight reduced to 3475 lbs. · T1-LP Ford Mustang FP350S restrictor increases from 70mm to 75mm. · Mercedes Benz AMG GT4 2017-2021 classified T1 Maximum at 3400 lbs minimum weight with HP-controlled SRO Power Level 2 engine. · B-Spec Hyundai Accent GS and Kia Rio restrictor increased from 36mm to 39mm flat plate. · T1 Dodge Viper ACR displacement rises to 8400 OEM, minimum weight drops to 3550 lbs. · T1 Limited T1 wording changed to clarify all T1 cars permitted specifications. · T1 Mazda RX-7 classified: 2700 lbs minimum weight, 44mm restrictor, 13B Rotary with single Garrett Turbo #3076. · B-Spec allows springs strapped to body for rebound control; removes requirement for OEM or kit bump stops. · B-Spec strut tower modifications permitted for camber adjustment only, limited to 1.75 degrees. · B-Spec Mazda2 10-14 undertray part numbers corrected to DO8C-56-110A, DO8C-56-311, DO7A-56-321. · T1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird, Pontiac GTO LS3 minimum weight reduced to 3475 lbs. · T1 Camaro maximum displacement 7011 loses 50 lbs, to 3500. · T1 removes 33mm brake rotor thickness limit; rotors now unrestricted on thickness. · B-Spec Nissan Versa S 2020- classified at 2700 lbs with 38mm restrictor, 1598cc engine. · Toyota/Scion IA Sedan (2016-2020) classified for B-Spec at 2700 lbs with 38mm FPR. · B-Spec Mazda 2 (10-14) replaces Bilstein B14 suspension kit with Powerflex rear bushings; adds radiator, exhaust headers, undertray. · 2007-2008 Honda Fit automatic added to B-Spec at 2525 lbs with 1499 cc engine. · T1 Mazda MX-5 Miata MazdaSpeed minimum weight rises to 2550 lbs, restrictor increases to 42mm. · T1 Chevrolet Corvette Cadillac XLR classified for model years through 2019. · B-Spec upper strut slotted plates no longer require manufacturer's original bolt holes or serve as reinforcement. · B-Spec upper strut slotted plates no longer must use manufacturer's original bolt holes. · T1 BMW E46/E36/Z3 minimum weight increases to 2700 lbs, 3.4L engine car to 2750 lbs. · B-Spec Mazda2 10-14 allows header PN 0000-06-2410 with 70 lb weight penalty. · T1 Dodge Viper SRT-10 restrictor increases from 45mm to 57mm. · T1 Chevrolet Corvette Cadillac XLR LS6 engine now permits Casting #799 heads with no other head modifications. · B-Spec Honda Fit and Mini Cooper models gain alternate transmission ratios and final drives to allow Setrab 50-119-7612 cooler. · B-Spec Honda Fit 2007-08 classified with 1499cc displacement, 2450mm wheelbase, 2525 lbs minimum weight. · B-Spec Ford Fiesta 5dr Hatchback allowed Eibach rear sway bar #35143.312 or #35143.320. · B-Spec restrictor range changes from 0.060" ±0.005" to 0.050"-0.079". · B-Spec rear window wipers and wiper motor removal now allowed. · T1 Ford Mustang Shelby/GT350/GT500 5.0L Coyote restrictor opens from 65mm to 70mm flat plate. · T1 Dodge Viper SRT-10 restrictor increases from 45mm to 57mm. · T1-LP Chevrolet Corvette C7 restrictor increases from 70 to 73 mm. · T1-LP Corvette Z06 06-13 now allows aluminum chassis replacement with equivalent OE steel chassis. · T1 Chevrolet Camaro with 6162 displacement minimum weight reduced to 3500 lbs. · T1-LP Chevrolet Corvettes C5 Z06, C6 Grand Sport, and Z06 dry sump kit notes clarified to remove contradictions. · B-Spec Mini R60 and R61 allow 4-lug hub conversion with specified bearings and brake rotors. · B-Spec Mazda2 10-14 header replacement allowed, minimum weight increases 2330 to 2380 lbs. · B-Spec Honda Fit model years expand from 09-12 to 09-14. · B-Spec Hyundai Accent GS and Kia Rio restrictor reduced from 40mm to 36mm flat plate. · B-Spec must use Hankook P205/50ZR15 Z214 C51 or Z217 rain tyres for SCCA Majors, Super Tour, Runoffs. · B-Spec tire rules clarified: Hankook Z214 dry and Z217 rain required at Majors/Super Tour/Runoffs after 6-1-2021; regional racing allows any DOT race tire through 2021. · B-Spec restrictor thickness set to 0.060 inches plus or minus 0.005 inches. · T1 LP removes 50 lbs weight allowance for stock headers, adds aero device allowance up to 100 lbs, permits headers. · B-Spec Hyundai Accent GS Hatchback 2013-2019 classified at 2525 lbs with 40mm flat plate restrictor. · B-Spec Mini Cooper Countryman R60 and Paceman R61 production years corrected from 11-13 to 11-16. · B-Spec Toyota Yaris Hatch model year spans corrected from 07-12 to 07-11 and 12-18 added. · B-Spec Mini Cooper all models ride height minimum 5 inches measured from metal under door rocker molding. · B-Spec allows removal or material modification of metal or plastic brake dust shields. · B-Spec Mini Cooper Clubman R55 11-15 permitted OBX header with 40mm flat plate restrictor. · T1 Ford Mustang Challenge 3-valve maximum displacement changes to 4600/5000. · T1 BMW E46 now allows carbon or fiberglass OEM-style dashboards with 25 pound penalty. · T1 Ford Mustang/Thunderbird limited to Shelby/Shelby GT350/GT500 models through 2018. · Dodge Viper ACR classified in T1 with 8400cc displacement, 3600 lbs minimum weight, 55mm restrictor. · BMW M2CS Club Sport classified in T1-LP Spec Lines effective 2021-02-01. · Porsche 997.1 GT3 Cup (2006-2011) classified in T1 at 3600cc, 3150 lbs minimum weight. · T1 Chevrolet Corvette Z06 years extended from 06-12 to 06-13. · B-Spec: Bilstein B14 suspension kits removed from all car spec lines; clarified B14 shock or strut use requires CRB approval of mounting adaptors. · B-Spec removes Chevrolet Sonic 12-19, clarifies Toyota Yaris Hatch 07-12 and Sedan 07-12. · T1 Corvette C8 Z51 gets wider wheels and tyres, weight drops 100 lbs to 3550. · B-Spec Mini Cooper R56 40mm flat plate restrictor requirement removed, suspension and header parts now allowed. · FE2 oil cooler wording clarified: optional air-to-oil cooler allowed, Setrab 50-625-7612 or equivalent max 13 inches wide by 6.5 inches high. · T1 rear wing Gurney flap wording clarified: Gurney flap in chord length and mounting height rules. · B-Spec wheelbase measurements converted from inches to millimeters for consistency across all cars. · T1 and T2 Corvettes may convert leaf spring suspension to coilover with 800 lb max spring rate allowed. · B-Spec Chevrolet Sonic 5dr Hatch and 4dr Sedan allow Setrab transmission cooler for automatic-equipped cars. · B-Spec: multiple models allow specific suspension kits and damper assemblies. · B-Spec sunroof retention wording removed, simplifying rules. · B-Spec Ford Fiesta 5dr gets 36mm restrictor, 4dr gets 34mm, Honda Fit 09-12 loses 25 lbs to 2525, Fit 15-20 restrictor reduced 32mm to 30mm, Mini Cooper 07-10 gets 40mm restrictor. · T1 Porsche 996 GT3 Cup eligible model years changed from 2002-2005 to 1998-2004. · T1 Corvette and Cadillac XLR permitted to install SCRSPLR-001 rear spoiler with OE bodywork. · T1 Gen 5 Camaro allowed 366mm OEM rear rotor and caliper without weight penalty. · T1 Porsche 996 Spec Lines now allows 996 Cup Replica Rear deck lid. · T1 Acura NSX Turbo World Challenge and Audi TTRS GTS 2011 now require DOT tires per GCR section 9.3. · B-Spec Sonic extended to 2019, Fiat 500 limited to 2015, Fiesta models extended to 2019, Fit expanded to 2015-2019. · B-Spec Mini Cooper R50, R55, R58, R60, R61 models newly classified at 2545–2625 lbs with 40mm restrictor for 12+ models. · B-Spec fog lamps must now be removed and holes completely covered, reversing prior allowance. · B-Spec Chevrolet Sonic 4dr Sedan (12-19) added at 2650 lbs with 32mm flat plate restrictor. · T1 BMW E46 wagon with S54 engine allowed; displacement corrected from 3200 to 3250cc. · B-Spec now permits automatic and CVT transmissions on all legal cars meeting spec line. · B-Spec automatic transmissions may use auxiliary coolers on case-by-case basis with part number approval. · T1 adds Subaru WRX/WRX STI 2005-2020 at 3000 lbs minimum weight with 46 mm restrictor. · T1 Ford Mustang GT (15-17) and GT5.0L (2018-) weight raised to 3500 lbs; Brembo BBK 380mm now at no penalty; restrictors removed from notes. · T1 Ford Mustang/Thunderbird 5000 Coyote OEM reclassified to include 2015–2017 and 2018+ model years with 65mm restrictor for 18+. · T1 BMW M3 E92 carbon dash allowed with 25 lb penalty. · T1 Corvette C5 Z06, C6 coupe, C6 Grand Sport, and Z06 may convert leaf springs to conventional coilover suspension. · Toyota Yaris Sedan 2007- added to B-Spec at 2400 lbs with 1491cc engine. · B-Spec adds 2011-2016 Ford Fiesta 4dr Sedan, 1596cc, 2495 lbs minimum weight. · B-Spec Kia Rio 5-door/LX years expanded to 2012-2019. · B-Spec Mazda2 (10-14) allows specific suspension, intake, exhaust, and bushing parts; removes air duct Mz26-117-33100. · B-Spec Mini Cooper production years corrected to 2011-13. · FE and FE2 minimum weight increased to 1270 lbs including driver; spring options and tire warmer ban added. · B-Spec Mazda 2, Fiat 500, 2007-10 Mini Cooper permitted to replace primary cat/exhaust manifold with approved header. · B-Spec removes year-specific eligibility and twelve-year competition window wording. · B-Spec Honda Fit model year expanded to include 2013, now covers 2009–2013. · T1-LP Chevrolet Camaro 1LE 2016- weight drops to 3500 lbs, restrictor increases to 70mm flat plate. · Ford Mustang Challenge returns to T1 as E&O, 4600 cc, 3300 lbs minimum, no restrictor. · T1 Chevrolet Corvette Cadillac XLR year range corrected from 04-09. · B-Spec 2007-10 Mini Cooper gains OBX header part #10-2101-2S as permitted E&O. · T1 Camaro, CTS, Firebird, GTO restrictor increases from 67mm to 70mm flat plate. · T2-T4 clarifies DOT tire requirements; must have minimum U speed rating and be DOT certified; touring spec line supersedes other rules. · Ford Mustang EcoBoost 3.5L classified in T1 at 3300 lbs minimum weight with 31mm restrictor. · T1 Corvette C5 body allowed C7 carbon aero parts, plus 50 lbs. · T1 Audi TTRS must conform to July 24th, 2015 revision 7 GTS rules instead of December 14th, 2011 revision 3. · T1 minimum ride height established at 3.5 inches, measured at rocker panel without driver. · T1 Porsche 928 S4/GTS-R minimum weight reduced to 3200 lbs, throttle restrictor removed. · Porsche 928 S4/928 GTS-R newly classified in T1 at 3500 lbs minimum with 60mm flat plate restrictor. · B-Spec added to GCR 9.3.26 fuel cell exception list; stock fuel tank permitted. · T1-LP Ford Mustang GT 5.0L 2018+ classified at 3400 lbs with 65mm flat plate restrictor. · Canadian Nissan Micra Cup Car classified in B-Spec at 2450 lbs with 1598cc engine, Micra Cup suspension kit allowed. · Toyota Yaris (12-18) newly classified in B-Spec with 1491cc engine, 2400 lbs minimum weight, specified suspension and intake allowed. · B-Spec exhaust system wording clarified: OEM or exact replacement catalysts permitted, stock oxygen sensors required, primary converter unmodified. · T1-LP Mustang GT350(R) spec line replaced with 2015+ model parameters including 5163cc engine, 3650 lbs curb weight, 315 tire size. · Ford Mustang FP350S (2018) classified in T1-LP at 3600 lbs with 18×11 wheels and 315 tires. · T1 suspension rules clarified: spherical bearings and bushings now explicitly permitted, alternate control arms allowed. · T1 Porsche 996 drops 200 lbs to 3000; 996 GT3 Cup drops 150 lbs to 3000; 997 drops 50 lbs to 3100. · Porsche 997 T1 Maximum now allows OEM PDK transmission alongside existing drivetrain options. · T1 Acura NSX Turbo World Challenge weight to 3100 lbs, restrictor to 44mm. · T1-T3 spec cars receive clarifications on permitted modifications, documentation requirements, and rule conformance; no performance changes.showhide
B-Spec Remove Redundant Language from Notes Sections #37337wordingneutralB-Spec Honda Fit AT, Fit CVT, Mazda2, Mini Cooper R50 MT and CVT, Toyota Yaris remove redundant notes language.
B-Spec Expire designated spec lines #37517removedneutralB-Spec removes Mini Cooper Countryman R60, Cooper Paceman R61, and two Nissan Versa generations effective 2/1/25.
B-Spec Set expiration date for Nissan Micra Cup Cars (Canadian) #37519wordingneutralB-Spec Nissan Micra Cup Car spec line expires 7/1/25 unless appeal submitted by 6/30/25.
T1 T1 Parity Compared to GT4 #37170weight +125 lbsslowerT1 Mustang gains 125 lbs to 3600, restrictor shrinks 65mm to 60mm. Corvette gains 50 lbs to 3500, restrictor shrinks 70mm to 67mm. BMW deleted.
T1 Clarification of Request Approval #37273 #37399engineunclearT1 E46 M3 Spec Line 1050 allows VAC Motorsports throttle body VAC-TB-S54 on 3.250L engine instead of Dinan.
T1 C8 Corvette Facts #37400weight -100 lbsfasterT1 Chevrolet Corvette C8 (2023-23) minimum weight reduced from 3600 lbs to 3500 lbs.
T1 Camaro Gen 5 Competitive Disadvantage #37440inductionfasterT1 Chevrolet Camaro Gen 5 restrictor increases from 75mm to 80mm flat plate.
T1 Tire Changes in the Rules for GT4 #37497tyres & wheelsunclearT1 Audi R8 GT4 Spec Line #4020 maximum tyre size changes to 315 DOT, 305/645, or 30/65-18 (f), 33/68-18 (r) Non-DOT.
B-Spec Remove wheelbase from spec lines and replace with Restrictor #36074inductionunclearB-Spec and C-Spec cars replace wheelbase spec with induction restrictor (mm) values, effective 2025-01-01.
B-Spec Bilstein Rear Shock Request for Hyundai Accent/Kia Rio #36965suspension & brakesneutralB-Spec Hyundai Accent and Kia Rio approve Bilstein B8 shock 33-187112 for rear suspension use.
T1 Changes to T1 Tires for GT4 and Other Cars #35383tyres & wheelsunclearT1 GT4 tire sizes adjusted across ten cars: most non-DOT rear to 305/660, Audi and McLaren 305/645, Camaro and Mustang 305/680.
T1 G82 M4 GT4 inclusion in T1 #35864cars addedneutralBMW M4 GT4 (G82) added to T1 GT4 at 3525 lbs minimum weight with Red power stick control.
T1 Alt. Clutch Allowance #36606wordingneutralT1 Spec Lines now permits 5.5 inch clutch in Engine Notes.
T1 BOP Changes Need Updates #36667weight -150 lbsfasterT1 GT4 Spec Line 4020 restrictor opens from 44mm to 45mm, minimum weight drops to 3400 lbs.
T1 Request Ford Performance Darkhorse R in T1 #37136cars addedneutralMustang Darkhorse R added to T1 homologated cars at 3,250 lbs minimum with 305/315 tires, ineligible for Runoffs until 3 Super Tour events.
T1 Car Mods for T1 Corvette under line item 1150 #37173wordingneutralT1 Corvette may roll or flatten wheel opening lips for tire clearance; plastic fenders may remove lips if edge thickness matches basic material.
T1 Increased Bore Throttle Bodies for E46 M3 S54 Engine #37273enginefasterT1 E46 M3 S54 can now use Dinan Throttle Body #D760-3400 on 3.250L engine.
B-Spec Scion IA/Toyota Yaris/Mazda 2 DY chassis suspension #35780suspension & brakesunclearB-Spec Toyota/Scion IA Sedan 16-20 allows ST Suspension Kit 13275022, requires three Super Tour weekends and OBD-II data submission.
B-Spec Clean up 07-08 Honda Fit AT Notes Section #36542suspension & brakesfasterHonda Fit AT 07-08 B-Spec and C-Spec: rear sway bar Progress #62.1060 and any cold air intake package now allowed.
B-Spec Update Tire Rules #35984tyres & wheelsneutralB-Spec and C-Spec restricted to Goodyear Eagle RS/RS-R P205/50R15 and 225/45R17 tires respectively; Hankook tires removed; wet/dry mixing prohibited.
B-Spec BOP help for the automatic B-Specs #36161weight -50 lbsfasterB-Spec Sonic restrictors increased to 5-6mm, Fit weight cut 50-25 lbs, Mini Cooper weight reduced 45 lbs, various restrictor adjustments.
B-Spec Require hood pins #36233wordingneutralB-Spec and C-Spec hood pins change from optional to recommended; factory release cable may be removed if pins used.
B-Spec Sonic Caliper Pistons #36238wordingneutralB-Spec and C-Spec Chevrolet Sonic and Cruze allow Babyface Fabrication brake caliper pistons.
B-Spec Clean up (15-19) Honda Fit MT & CVT Notes Sections #36068wordingneutralB-Spec Honda Fit MT & CVT 15-19: cleaned up allowed parts notes, CVT gains Setrab transmission cooler option.
B-Spec Set expiration date for Nissan Versa (09-11) #36069wordingneutralB-Spec Nissan Versa (09-11) spec line expires 1/1/2025 unless appeal filed by 12/1/2024.
B-Spec Correct error for rear brakes of Hyundai/Kia #36174wordingneutralB-Spec Hyundai Accent rear brakes corrected to 10.3 disc; Kia Rio rear brakes corrected to 10.3 disc.
B-Spec Add B14 Kit Part # to Sonic Spec line In #35969wordingneutralB-Spec and C-Spec Chevrolet Sonic Bilstein B14 kit #47-171725 verified compatible, suspension wording clarified.
B-Spec Eliminate redundant sway bar end link part #s from notes In #35970wordingneutralB-Spec Mazda2 and multiple Mini Cooper models eliminate redundant sway bar end link part number notes.
B-Spec Update Fiat 500 Spec line In #35990wordingneutralB-Spec Fiat 500 spec line changes from model year 2012–15 to 2012–17.
B-Spec Update (15-19) Honda Fit #36067weight +25 lbsslowerB-Spec Honda Fit 15-19 CVT weight increases to 2550 lbs, restrictor to 31mm.
B-Spec Delete trim levels/update language for spec lines #35746wordingneutralB-Spec model descriptions standardized: trim levels and door count designations removed or replaced with body style wording.
B-Spec Wheel Rules #36066wordingneutralB-Spec and C-Spec wheels must be same thickness spacers all four corners; wording clarified on offset and protrusion rules.
T1 Please Expedite classing the C63 Mercedes #35987cars addedneutralMercedes AMG-C63 S (2023) classified in T1 with 4000 lbs minimum weight and 3700 restrictor.
B-Spec Change restrictor from 30mm to 31mm (2015+ Honda Fit) and add 50# #34857inductionfasterB-Spec Honda Fit MT 2015-19 restrictor increases 30mm to 31mm, weight rises 2525 to 2550 lbs.
B-Spec Wheel Offset and Spacer Revision #35466tyres & wheelsfasterB-Spec and C-Spec now permit wheels of any offset if tire doesn't protrude beyond fender; spacers allowed with differing left-right offsets per axle.
B-Spec Set Expiration Date for Unused Spec Lines #35742wordingneutralB-Spec Mini Cooper Countryman R60, Paceman R61, and Nissan Versa 1797cc spec lines expire 1/1/2025 unless appealed by 12/1/2024.
T1 Honda S2000 #35582cars addedneutralT1 Honda S2000 classified with 2400 lb minimum weight, 2950 cc displacement, 4.75" supercharger pulley.
B-Spec BOP Adjustment for Yaris iA, 2020+ Versa, and 07-08 Honda Fit #35382weight -125 lbsfasterB-Spec Honda Fit 07-08 loses 125 lbs to 2400; Versa S 2020+ loses 150 lbs to 2550; Yaris iA 16-20 loses 250 lbs to 2450.
B-Spec 07-08 Honda Fit Rear Sway Bar part # #35473wordingneutralB-Spec Honda Fit 07-08 rear sway bar part number changed to Progress #62.1060.
T1 9.1.9.1 T1 new category item/ line 26 rule to expire Jan 1 2023 #35411cars addedneutralPontiac GTO 2006-2009 LS1 added to T1 as Spec Line 1590, 5700 cc, 3400 lbs minimum.
B-Spec Eliminate Redundant Trans Cooler Rule #35353wordingneutralB-Spec and C-Spec eliminate case-by-case auxiliary transmission cooler approval requirement.
B-Spec Fix Sonic Hatchback MT Spec Line #35371wordingneutralB-Spec Chevrolet Sonic 5dr Hatch MT allows aluminum radiator #ZZP-ZZ013.
B-Spec Split Spec Line of Automatic and Manual 2nd Gen (09-14) Fit #35251wordingneutralB-Spec Honda Fit MT (09-14) and AT now split into separate spec lines with distinct allowances.
B-Spec Equalize Mazda 2 Headers and clean up spec line #35259weightslowerB-Spec Mazda 2 10-14 weight increases 70 lbs to 2350, cat-delete headers now permitted.
B-Spec Rear Sway Bar Request for Nissan Versa and Versa Note 2013- #35323suspension & brakesneutralB-Spec Nissan Versa and Versa Note 2013-2019 now permit Hardrace HR-Q0146 19mm rear sway bar.
T1 C8 Corvette T1 Restrictor Plate Request #35213inductionfasterC8 Corvette T1 restrictor plate increases from 70mm to 72mm flat plate.
T1 The Cars Have Expired #35379removedneutralT1 NEW class removes 23 spec lines including Acura NSX, Ferrari, Porsche 996, Nissan Z cars, and others; Porsche 997 spec line 1680 expiration removed.
B-Spec B-Spec Hankook Tire for Regionals #35055tyres & wheelsneutralB-Spec allows Hankook tires at regionals only through 6-30-2024; Goodyear only from 7-1-2024 for all events.
B-Spec Clarifying the ECU and Data Acquisition language #35236wordingneutralB-Spec and C-Spec ECU and data acquisition rules clarified: ECU must be unaltered OE, no device capable of altering ECU characteristics permitted; data acquisition expanded to allow tachometer, air-fuel ratio, cylinder head temperature sen…
T1 GT4 batch adjustment in T1 #35162other -85 lbsunclearT1-GT4 batch adjustments: five cars lighter, two heavier, restrictors and ECU maps changed, five models now eligible for Runoffs.
B-Spec Mazda 3i 2010-2013 5-Speed Manual Gear Ratios #34820wordingunclearC-Spec Mazda 3i 10-13 third gear ratio corrected from 3.84 to 1.84.
B-Spec Error Correction #34955wordingneutralC-Spec Dodge Dart 14-16 bore x stroke corrected to 88.0 x 82.0 mm, displacement to 1998 cc.
T1 New T1 add spec line for C5 corvette LS2 engines (Copy from C6) #33764cars addedneutralT1 Chevrolet Corvette C5 LS2 added with 6000cc displacement, 3300 lbs minimum weight, 72mm flat plate restrictor.
T1 C7 Corvette Rule Change Request #34897cars addedneutralT1 Chevrolet Corvette C7 (14-19) including Z51, Grandsport newly classified as homologated car.
T1 Camaro Gen 5 Weight Reduction Due to Competitive Disadvantage #35092weight -75 lbsfasterT1 Gen 5 Camaro minimum weight drops 75 lbs to 3475; restrictor increases 70mm to 75mm.
T1 Addendum to Letter #35022: Drivetrain Rule #35105wordingneutralT1 Aston Martin Vantage permitted to use OEM Sportshift II transmission.
T1 2004 - 2006 Pontiac GTO Re-Integration Back Into T1 #34403cars addedneutralPontiac GTO 2006-2009 re-integrated into T1 with LS2 at 3400 lbs, 72mm restrictor, and LS3 at 3500 lbs, 61mm restrictor.
T1 Request to Classify Porsche 997-1 GT3 Cup #34561cars addedneutralT1 Porsche 997-1 GT3 Cup added at spec line 4210, minimum weight 3050 lbs.
B-Spec B-Spec Tire #35034tyres & wheelsneutralB-Spec adds Goodyear Eagle RS dry and wet tires as options alongside Hankook; Hankook restricted to regional events from 2024.
B-Spec Initial car classifications and spec lines #34461cars addedneutralC-Spec adds Chevrolet Cruze, Ford Focus, Honda Civic, Mazda 3i, Toyota Corolla, VW Jetta; updates Dodge Dart, Mazda3s, Toyota Corolla specs.
T1 Why no Camaro? #34421cars addedneutralChevrolet Camaro GT4-R classified in T1 GT4 Spec Line 4035, minimum weight 3375 lbs, 315 max tire, 63mm restrictor, ineligible for Runoffs.
T1 Request to Remove Expiration from T1 spec lines #1350 & #1370 #34470wordingneutralT1 Dodge Viper ACR / SRT RT-10 and ACR/ACR-X spec lines 1350 and 1370 remove 12/23 expiration.
T1 Remove #34475wordingneutralT1 GT4 McLaren 570S, Mercedes AMG GT4, and Porsche 718 Cayman GT4 CS MR now eligible for Runoffs competition.
T1 Error in T1 GT4 numbering scheme- #34578wordingneutralT1 GT4 BMW M4 Spec Line Number changed from 4050 to 4030.
T1 C5 Approved Aero That Was Mistakenly Deleted #34374aerofasterT1 Corvette C5 gains approved aero parts: carbon rear spoiler, vented front splitter, side skirts, with 50 lb weight reduction allowed.
B-Spec Hyundai Accent Restrictor Plate #34331inductionfasterB-Spec Hyundai Accent GS Hatchback restrictor plate increases from 39mm to 41mm.
B-Spec Hyundai Accent 2012 Model #34332wordingneutralB-Spec Hyundai Accent GS Hatchback model years corrected from 13–19 to 12–19.
T1 Viper Cleanup #34107inductionfasterT1 Dodge Viper ACR/ACR-X restrictor increases from 50mm to 60mm flat plate.
T1 Viper 8300 OEM FPR Size #34268inductionunclearT1 Dodge Viper ACR/ACR-X: Spec Line 1370 restrictor increases to 55mm, Line 1390 decreases to 55mm.
T1 Ford Mustang S197 (05-14) Clarification #34450wordingneutralT1 Ford Mustang S197 05-14 now requires OEM 8.8 differential housing.
T1 Gen 5 Camaro Engine #33875cars addedneutralT1 Chevrolet Camaro Gen 5 LS7 gets two spec lines: 1131 with 70mm restrictor, 1136 with 53mm restrictor, both 3450 lbs minimum.
T1 Inquiry to letter #33682 #34071engineslowerT1 Chevrolet Camaro Gen 5, Corvette C5 and C6: engine resleeve restricted to stock parameters only, no longer LS3 bore/stroke.
B-Spec Allow ZZP Sonic Aluminum Radiator 1.68 #33660otherfasterB-Spec and C-Spec Chevrolet Sonic allows ZZP aluminum radiator #ZZP-ZZ013; Hatch MT restrictor increases to 34mm.
B-Spec Fasteners for Bumper Caps #33797wordingneutralB-Spec and C-Spec bumper caps now allow positive fasteners like machine screws and T-nuts or rivet-nuts; self-drilling and sheet metal screws prohibited.
B-Spec Allow CAN Bus Connection to Data Systems #33806wordingneutralB-Spec and C-Spec allow CAN bus connections to data systems for monitoring only; systems must not send data.
B-Spec Request Ford Fiesta weight reduction 25lbs #33890weight -25 lbsfasterB-Spec Ford Fiesta 5dr and 4dr lose 25 lbs each, to 2470 lbs minimum weight.
B-Spec BoB Adjustments #34208weight -25 lbsunclearB-Spec Ford Fiesta 5dr and 4dr lose 25 lbs each to 2470; Honda Fit MT and CVT lose 50 lbs each to 2525; Mazda2 loses 50 lbs to 2280; Kia Rio restrictor increases from 39 to 41 mm; Mini Cooper variants gain 75 lbs to 2675 with larger restri…
B-Spec T5 Ride Height Rules. #33552suspension & brakesneutralB-Spec minimum ride height set to 6 inches, C-Spec to 5½ inches.
B-Spec T5 Spring Allowance #33557suspension & brakesneutralB-Spec springs capped at 500# front and rear; C-Spec at 600# front, 800# rear; both may be strapped to body.
B-Spec T5 Wheel Minimum Weight #33558tyres & wheelsneutralB-Spec wheels minimum weight set to 13 lbs, C-Spec to 17 lbs.
B-Spec Threaded Metal Inserts for Plastic Intake Manifolds #34164wordingneutralB-Spec and C-Spec allow metal threaded inserts in plastic intake manifolds for throttle body fasteners.
T1 Request to reinstate T1 S197 Mustang #34048cars addedneutralT1 Ford Mustang S197 (05-14) reinstated with 3550 lbs minimum weight, 75mm restrictor, Voodoo engine permitted.
B-Spec T5 Rules Feedback #33595wordingneutralB-Spec and C-Spec wording clarified: CATEGORY to CATEGORIES, rules priority clarified for tire sizes, rim widths, springs, anti-roll bars, performance equipment.
T1 T1 GT4 adjustments #33786wordingneutralT1 GT4 weights clarified for nine cars, ranging from 3200 lbs Porsche 718 Cayman to 3575 lbs Aston Martin.
T1 Touring 1 Tire Sizes #34191tyres & wheelsfasterT1-GT4 McLaren 570S and Mercedes AMG GT4 front tires widen to 315 mm.
T1 Clarification for Camaro Gen5 2010-2015 #33739inductionslowerT1 Chevrolet Camaro Gen5 LS3-6160 adds 70mm flat plate restrictor, weight 3550 lbs.
B-Spec Early Model Mini #33363inductionfasterB-Spec Mini Cooper R56 MT/AT and Clubman R55 fuel pressure regulator increased from 40mm to 41mm with OE catalyst.
B-Spec Helper Versus Tender springs. #33866suspension & brakesslowerB-Spec may use helper springs up to 500 pounds rate; tender springs now prohibited.
T1 Sequential Gearbox Limitations in T1 #33691wordingneutralT1 cars with aftermarket sequential transmissions get 10-inch max bellhousing; non-sequential cars gain 100 lbs weight break.
T1 T1 GT4 adjustments #33786weightfasterT1 GT4 all nine cars lose 125 lbs minimum weight with driver, from 3200–3575 to 3075–3450.
T1 Sunset of pre 2023 Touring 1 Rules. #33916wordingneutralT1 removes GCR Section 9.1.9.1.A. and T1 Spec Lines entirely, sunsetting pre-2023 Touring 1 rules.
B-Spec Split up Spec lines for Automatic/Manual 2nd Gen Fit #33292enginefasterB-Spec Honda Fit 09-14 Automatic now allows aftermarket exhaust/header; Manual unchanged.
T1 Corrections to T1 Spec Lines #33678tyres & wheelsunclearGT4 McLaren 570S maximum tire size changes to 285 front, 315 rear.
B-Spec Request to Split Spec Lines for Automatic Models #33270wordingneutralB-Spec Chevrolet Sonic and Honda Fit and Mini Cooper split into separate manual and automatic spec lines with distinct transmission ratios and final drives.
B-Spec Tire Rule Request #33350tyres & wheelsneutralB-Spec tire rule adds Hankook 200/580R15 Z217 as alternative to 205/50R15 C51; no mixing wet and dry.
T1 GT4 section to Current T1 Rules. #33632cars addedneutralEight GT4 models added to T1 with weights from 3200 to 3575 lbs and restricted power per SRO 2022 rules.
B-Spec Utilize the Data - Make BoP Changes #32179weight -225 lbsfasterB-Spec Honda Fit 15-19 weight drops 225 lbs to 2575 lbs.
B-Spec Request new Mazda Rear Swaybar #32769wordingneutralB-Spec Mazda2 10-14 rear sway bar now allows part 0000-04-2203-RR or 0000-04-2312.
T1 Correct Camaro Spec Line From Letter #30791 response to 3475lbs #32824weight -25 lbsfasterT1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird, Pontiac GTO 6162 OEM minimum weight reduced to 3475 lbs.
T1 Fix FP350S limited prep and Shelby 350 full prep issues #31680inductionfasterT1-LP Ford Mustang FP350S restrictor increases from 70mm to 75mm.
T1 Request to Classify AMG GT4 #32610cars addedneutralMercedes Benz AMG GT4 2017-2021 classified T1 Maximum at 3400 lbs minimum weight with HP-controlled SRO Power Level 2 engine.
B-Spec Request to Remove Part Numbers from Kia/Hyundai Spec Lines #32378inductionslowerB-Spec Hyundai Accent GS and Kia Rio restrictor increased from 36mm to 39mm flat plate.
T1 Viper/Z06 Parity #31942weight -50 lbsfasterT1 Dodge Viper ACR displacement rises to 8400 OEM, minimum weight drops to 3550 lbs.
T1 Discrepancy in T1 allowances #32293wordingneutralT1 Limited T1 wording changed to clarify all T1 cars permitted specifications.
B-Spec Request spring attachment #31351suspension & brakesneutralB-Spec allows springs strapped to body for rebound control; removes requirement for OEM or kit bump stops.
B-Spec Limit Rear Camber to 1.75 Degrees Section 9.1.10.E.35 #31393suspension & brakesslowerB-Spec strut tower modifications permitted for camber adjustment only, limited to 1.75 degrees.
B-Spec Letter 31442 Part# Correction #32060wordingneutralB-Spec Mazda2 10-14 undertray part numbers corrected to DO8C-56-110A, DO8C-56-311, DO7A-56-321.
B-Spec Request to Classify 2020-21 Versa S #30759cars addedneutralB-Spec Nissan Versa S 2020- classified at 2700 lbs with 38mm restrictor, 1598cc engine.
B-Spec Request to Classify the Toyota IA sedan & Scion IA Sedan for 2022 #31045cars addedneutralToyota/Scion IA Sedan (2016-2020) classified for B-Spec at 2700 lbs with 38mm FPR.
B-Spec Request to add 2007-2008 Honda Fit #30853cars addedneutral2007-2008 Honda Fit automatic added to B-Spec at 2525 lbs with 1499 cc engine.
T1 Turbo Miata Help #31315weight +200 lbsslowerT1 Mazda MX-5 Miata MazdaSpeed minimum weight rises to 2550 lbs, restrictor increases to 42mm.
T1 Fix the T1 Corvette heading #31528wordingneutralT1 Chevrolet Corvette Cadillac XLR classified for model years through 2019.
B-Spec Rules Clarification of Body and Camber Plates #30814suspension & brakesneutralB-Spec upper strut slotted plates no longer require manufacturer's original bolt holes or serve as reinforcement.
B-Spec Rules Clarification of Body and Camber Plates #30814suspension & brakesfasterB-Spec upper strut slotted plates no longer must use manufacturer's original bolt holes.
T1 T1 E46 BOP E&O for Letter # 29970 #30934weight +100 lbsslowerT1 BMW E46/E36/Z3 minimum weight increases to 2700 lbs, 3.4L engine car to 2750 lbs.
T1 Request BoP for the Viper in 1 LP #29968inductionfasterT1 Dodge Viper SRT-10 restrictor increases from 45mm to 57mm.
T1 LS6 Alternative Head Question #30074wordingneutralT1 Chevrolet Corvette Cadillac XLR LS6 engine now permits Casting #799 heads with no other head modifications.
B-Spec Transmission Cooler Requests #30079wordingneutralB-Spec Honda Fit and Mini Cooper models gain alternate transmission ratios and final drives to allow Setrab 50-119-7612 cooler.
B-Spec Request to classify the 07 Honda Fit #30083cars addedneutralB-Spec Honda Fit 2007-08 classified with 1499cc displacement, 2450mm wheelbase, 2525 lbs minimum weight.
B-Spec Request Ford Fiesta Eibach Rear Sway Bar Part Number 35143.320 #30340otherneutralB-Spec Ford Fiesta 5dr Hatchback allowed Eibach rear sway bar #35143.312 or #35143.320.
B-Spec Restrictor rule #30474inductionfasterB-Spec restrictor range changes from 0.060" ±0.005" to 0.050"-0.079".
B-Spec Rear wipers on all cars #30585weightfasterB-Spec rear window wipers and wiper motor removal now allowed.
T1 T1-LP - Add Performance Pack, Bullet, Mach 1 to 18+ Mustang #29849inductionfasterT1 Ford Mustang Shelby/GT350/GT500 5.0L Coyote restrictor opens from 65mm to 70mm flat plate.
T1 Request BoP for the Viper in 1 LP #29968inductionfasterT1 Dodge Viper SRT-10 restrictor increases from 45mm to 57mm.
T1 Request to classify C7 and 13Viper in T1 LP #29969inductionfasterT1-LP Chevrolet Corvette C7 restrictor increases from 70 to 73 mm.
T1 Request LP Z06 steel chassis #30589wordingneutralT1-LP Corvette Z06 06-13 now allows aluminum chassis replacement with equivalent OE steel chassis.
T1 Request For Reduction in Weight/Penalties for Camaro #30443weightfasterT1 Chevrolet Camaro with 6162 displacement minimum weight reduced to 3500 lbs.
T1 Fix dry sump Contradictions in T1-LP vs T2 #30596wordingneutralT1-LP Chevrolet Corvettes C5 Z06, C6 Grand Sport, and Z06 dry sump kit notes clarified to remove contradictions.
B-Spec Allow 4 lug hub conversion to R60 and R61 MINI #29863wordingneutralB-Spec Mini R60 and R61 allow 4-lug hub conversion with specified bearings and brake rotors.
B-Spec Honda Fit Years on Spec Line #30078wordingneutralB-Spec Honda Fit model years expand from 09-12 to 09-14.
B-Spec Hyundai/Kia restrictor size incorrect #30380inductionslowerB-Spec Hyundai Accent GS and Kia Rio restrictor reduced from 40mm to 36mm flat plate.
B-Spec Clarify tire compound in rules #30387tyres & wheelsneutralB-Spec must use Hankook P205/50ZR15 Z214 C51 or Z217 rain tyres for SCCA Majors, Super Tour, Runoffs.
B-Spec Spec Tire Recommendation #29480tyres & wheelsneutralB-Spec tire rules clarified: Hankook Z214 dry and Z217 rain required at Majors/Super Tour/Runoffs after 6-1-2021; regional racing allows any DOT race tire through 2021.
B-Spec Make restrictor thickness unique for B Spec #30349wordingunclearB-Spec restrictor thickness set to 0.060 inches plus or minus 0.005 inches.
T1 T1 LP Aero adjustments #30196aerounclearT1 LP removes 50 lbs weight allowance for stock headers, adds aero device allowance up to 100 lbs, permits headers.
B-Spec Request to Classify Hyundai Accent (RB) 2012-2019 #29484cars addedneutralB-Spec Hyundai Accent GS Hatchback 2013-2019 classified at 2525 lbs with 40mm flat plate restrictor.
B-Spec Countryman production years incorrect #29864wordingneutralB-Spec Mini Cooper Countryman R60 and Paceman R61 production years corrected from 11-13 to 11-16.
B-Spec Toyota Yaris Model Year Corrections #29896wordingneutralB-Spec Toyota Yaris Hatch model year spans corrected from 07-12 to 07-11 and 12-18 added.
B-Spec Correction spec lines for ride height Mini Cooper all models #29952wordingneutralB-Spec Mini Cooper all models ride height minimum 5 inches measured from metal under door rocker molding.
B-Spec Request to Allow Removal of Stock Brake Dust Shields #29981suspension & brakesneutralB-Spec allows removal or material modification of metal or plastic brake dust shields.
B-Spec Request to allow OBX header and restrictor to R55 Clubman 08-10 #30024engineunclearB-Spec Mini Cooper Clubman R55 11-15 permitted OBX header with 40mm flat plate restrictor.
T1 Request to Clarify Miller Mustang Classification #28728engineunclearT1 Ford Mustang Challenge 3-valve maximum displacement changes to 4600/5000.
T1 BMW E46 Carbon Dash #29806weightslowerT1 BMW E46 now allows carbon or fiberglass OEM-style dashboards with 25 pound penalty.
T1 Request to Update T1 Mustang Spec Line #30001wordingneutralT1 Ford Mustang/Thunderbird limited to Shelby/Shelby GT350/GT500 models through 2018.
T1 Class BMW M2CS Club Sport #30195cars addedneutralBMW M2CS Club Sport classified in T1-LP Spec Lines effective 2021-02-01.
T1 997.1 GT3 Cup #30229cars addedneutralPorsche 997.1 GT3 Cup (2006-2011) classified in T1 at 3600cc, 3150 lbs minimum weight.
T1 Correct T1 Limited Prep Years #29708wordingneutralT1 Chevrolet Corvette Z06 years extended from 06-12 to 06-13.
B-Spec Request clarification of B14 shock package for any and all cars #29483suspension & brakesneutralB-Spec: Bilstein B14 suspension kits removed from all car spec lines; clarified B14 shock or strut use requires CRB approval of mounting adaptors.
B-Spec Cleanup of spec lines #29495removedneutralB-Spec removes Chevrolet Sonic 12-19, clarifies Toyota Yaris Hatch 07-12 and Sedan 07-12.
T1 Changes to Corvette C8 #29898tyres & wheels -100 lbsfasterT1 Corvette C8 Z51 gets wider wheels and tyres, weight drops 100 lbs to 3550.
B-Spec Allowance Versus Requirement for R56 Mini Cooper #29127suspension & brakesfasterB-Spec Mini Cooper R56 40mm flat plate restrictor requirement removed, suspension and header parts now allowed.
FE2 FE/FE2 Oil Cooler #29293wordingneutralFE2 oil cooler wording clarified: optional air-to-oil cooler allowed, Setrab 50-625-7612 or equivalent max 13 inches wide by 6.5 inches high.
B-Spec Request to change units on wheelbase for consistency with wording #28786wordingneutralB-Spec wheelbase measurements converted from inches to millimeters for consistency across all cars.
T1 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.
B-Spec Transmission cooler for automatic equipped cars #28171otherneutralB-Spec Chevrolet Sonic 5dr Hatch and 4dr Sedan allow Setrab transmission cooler for automatic-equipped cars.
B-Spec Spring Update for all models #28384suspension & brakesneutralB-Spec: multiple models allow specific suspension kits and damper assemblies.
B-Spec B-Spec Balance of Performance based on 2018 and 2019 seasons #28394induction -25 lbsslowerB-Spec Ford Fiesta 5dr gets 36mm restrictor, 4dr gets 34mm, Honda Fit 09-12 loses 25 lbs to 2525, Fit 15-20 restrictor reduced 32mm to 30mm, Mini Cooper 07-10 gets 40mm restrictor.
T1 Additional Clarification on 996 Cup in T1 From Letter #28040 #28060wordingneutralT1 Porsche 996 GT3 Cup eligible model years changed from 2002-2005 to 1998-2004.
T1 Request SPEC Corvette Rear Spolier #28182aeroneutralT1 Corvette and Cadillac XLR permitted to install SCRSPLR-001 rear spoiler with OE bodywork.
T1 T1 Rear Brake Rotor Size Exemption for Gen 5 Camaro #28402wordingneutralT1 Gen 5 Camaro allowed 366mm OEM rear rotor and caliper without weight penalty.
T1 Request 996 GT3 Trunk for Wing Allowance. #28153wordingneutralT1 Porsche 996 Spec Lines now allows 996 Cup Replica Rear deck lid.
T1 All Touring, Change DOT Tire Language 9.1.9.1, 9.3.45 #28452wordingneutralT1 Acura NSX Turbo World Challenge and Audi TTRS GTS 2011 now require DOT tires per GCR section 9.3.
B-Spec Request for Model Years Updating #27850wordingneutralB-Spec Sonic extended to 2019, Fiat 500 limited to 2015, Fiesta models extended to 2019, Fit expanded to 2015-2019.
B-Spec Request to classify Min Cooper models #27861cars addedneutralB-Spec Mini Cooper R50, R55, R58, R60, R61 models newly classified at 2545–2625 lbs with 40mm restrictor for 12+ models.
B-Spec remove fog lights #27947wordingneutralB-Spec fog lamps must now be removed and holes completely covered, reversing prior allowance.
B-Spec add sonic sedan #27948cars addedneutralB-Spec Chevrolet Sonic 4dr Sedan (12-19) added at 2650 lbs with 32mm flat plate restrictor.
T1 Request for E46 wagon with S54 engine in T1 #27427wordingneutralT1 BMW E46 wagon with S54 engine allowed; displacement corrected from 3200 to 3250cc.
B-Spec Request for Automatic Transmission Inclusion #27686wordingneutralB-Spec now permits automatic and CVT transmissions on all legal cars meeting spec line.
B-Spec Request to Add Transmission Coolers to Automatics #27687otherneutralB-Spec automatic transmissions may use auxiliary coolers on case-by-case basis with part number approval.
T1 Request to include Subaru WRX/STI 02-18 in T1 #24916cars addedneutralT1 adds Subaru WRX/WRX STI 2005-2020 at 3000 lbs minimum weight with 46 mm restrictor.
T1 Request Ford Mustang FP350S T1-LP weight and restrictor change #26662weight +100 lbsslowerT1 Ford Mustang GT (15-17) and GT5.0L (2018-) weight raised to 3500 lbs; Brembo BBK 380mm now at no penalty; restrictors removed from notes.
T1 Request to classify Ford Coyote 3rd Gen OEM #27145cars addedslowerT1 Ford Mustang/Thunderbird 5000 Coyote OEM reclassified to include 2015–2017 and 2018+ model years with 65mm restrictor for 18+.
T1 Request alternate dashboard #27276weightslowerT1 BMW M3 E92 carbon dash allowed with 25 lb penalty.
T1 Request for Allowance of Coil Springs on Limited Prep C6 Corvette #27713suspension & brakesfasterT1 Corvette C5 Z06, C6 coupe, C6 Grand Sport, and Z06 may convert leaf springs to conventional coilover suspension.
B-Spec Add Yaris Sedan #26797cars addedneutralToyota Yaris Sedan 2007- added to B-Spec at 2400 lbs with 1491cc engine.
B-Spec Add 2011-2016 Fiesta Sedan #26798cars addedneutralB-Spec adds 2011-2016 Ford Fiesta 4dr Sedan, 1596cc, 2495 lbs minimum weight.
B-Spec add 2015-2019 Kia Rio #26799cars addedneutralB-Spec Kia Rio 5-door/LX years expanded to 2012-2019.
B-Spec Error and Omissions #27858suspension & brakesneutralB-Spec Mazda2 (10-14) allows specific suspension, intake, exhaust, and bushing parts; removes air duct Mz26-117-33100.
B-Spec Request for Correction of Production Years for Mini Cooper #27226wordingneutralB-Spec Mini Cooper production years corrected to 2011-13.
FE2 FE / FE2 Update Rules #27624weightslowerFE and FE2 minimum weight increased to 1270 lbs including driver; spring options and tire warmer ban added.
B-Spec Request for Corrections to 9.1.10 E Item #27 D and E #27224inductionfasterB-Spec Mazda 2, Fiat 500, 2007-10 Mini Cooper permitted to replace primary cat/exhaust manifold with approved header.
B-Spec Remove wording in the B-spec rules #27388wordingneutralB-Spec removes year-specific eligibility and twelve-year competition window wording.
B-Spec Request to add 2013 Honda Fit model year #27491cars addedneutralB-Spec Honda Fit model year expanded to include 2013, now covers 2009–2013.
T1 T1 LP 2016 Camaro and Later #27198weight -100 lbsfasterT1-LP Chevrolet Camaro 1LE 2016- weight drops to 3500 lbs, restrictor increases to 70mm flat plate.
T1 Request to return Ford Mustang Challenge Car to T1 #26751cars addedneutralFord Mustang Challenge returns to T1 as E&O, 4600 cc, 3300 lbs minimum, no restrictor.
T1 Correct years in T1 FP Corvette spec #27023wordingneutralT1 Chevrolet Corvette Cadillac XLR year range corrected from 04-09.
B-Spec Request to allow OBX Header for 2007-10 Mini Cooper #26977wordingneutralB-Spec 2007-10 Mini Cooper gains OBX header part #10-2101-2S as permitted E&O.
T1 Request BoP Baten - T1 Camaro - Follow up to Letter # 26145 #26900inductionfasterT1 Camaro, CTS, Firebird, GTO restrictor increases from 67mm to 70mm flat plate.
T1 Clarify DOT tires touring #26556tyres & wheelsneutralT2-T4 clarifies DOT tire requirements; must have minimum U speed rating and be DOT certified; touring spec line supersedes other rules.
T1 Request to Classify EcoBoost Mustang #25841cars addedneutralFord Mustang EcoBoost 3.5L classified in T1 at 3300 lbs minimum weight with 31mm restrictor.
T1 Request Corvette aerodynamic aids #26265aeroslowerT1 Corvette C5 body allowed C7 carbon aero parts, plus 50 lbs.
T1 Audi TTRS VTS Documentation Revision #26578wordingunclearT1 Audi TTRS must conform to July 24th, 2015 revision 7 GTS rules instead of December 14th, 2011 revision 3.
T1 Request Ride Height Clarification #26599wordingneutralT1 minimum ride height established at 3.5 inches, measured at rocker panel without driver.
T1 Request to classify the Porsche 928GTS/S4 in Touring 1 #26315cars addedneutralPorsche 928 S4/928 GTS-R newly classified in T1 at 3500 lbs minimum with 60mm flat plate restrictor.
B-Spec Request to add B-Spec to GCR 9.3.26 fuel cell #26132wordingneutralB-Spec added to GCR 9.3.26 fuel cell exception list; stock fuel tank permitted.
T1 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.
B-Spec Request to classify Canadian Nissan Micra Cup cars #25216cars addedneutralCanadian Nissan Micra Cup Car classified in B-Spec at 2450 lbs with 1598cc engine, Micra Cup suspension kit allowed.
B-Spec Request updated Toyota Yaris Spec Lines #25483cars addedneutralToyota Yaris (12-18) newly classified in B-Spec with 1491cc engine, 2400 lbs minimum weight, specified suspension and intake allowed.
B-Spec Update wording of exhaust #26022wordingneutralB-Spec exhaust system wording clarified: OEM or exact replacement catalysts permitted, stock oxygen sensors required, primary converter unmodified.
T1 Class 2015+ Mustang GT350(R) #21466wordingneutralT1-LP Mustang GT350(R) spec line replaced with 2015+ model parameters including 5163cc engine, 3650 lbs curb weight, 315 tire size.
T1 Request to Classify Ford FP350S in T1-LP #25341cars addedneutralFord Mustang FP350S (2018) classified in T1-LP at 3600 lbs with 18×11 wheels and 315 tires.
T1 Amendment to Request #25555 #25556wordingneutralT1 suspension rules clarified: spherical bearings and bushings now explicitly permitted, alternate control arms allowed.
T1 Request to balance 996 v 997 T1 weight #25658weightfasterT1 Porsche 996 drops 200 lbs to 3000; 996 GT3 Cup drops 150 lbs to 3000; 997 drops 50 lbs to 3100.
T1 Request to Add PDK Transmission to 997 Porsche Spec Line #25668wordingneutralPorsche 997 T1 Maximum now allows OEM PDK transmission alongside existing drivetrain options.
T1 T1 World Challenge/Grand AM Spec Cars #25687weightslowerT1 Acura NSX Turbo World Challenge weight to 3100 lbs, restrictor to 44mm.
T1 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.
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 T1" is the class's best as a share of T1'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 T1'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.