AS vs STL vs GTL vs SMX pace at Michelin Raceway Road Atlanta
Quickest here:AS 1:34.642 Michael Kamalian, Atlanta Region SCCA Hoosier Super Tour @ Michelin Raceway Road Atlanta race · STL 1:35.212 Danny Steyn, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta race · GTL 1:36.536 Peter Shadowen, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta race · SMX 1:24.667 Tyler Gonzales, Atlanta Region SCCA Hoosier Super Tour @ Michelin Raceway Road Atlanta race
ASSTLGTLSMXsolid race · dashed qualifying · slower is lower
ASSTLGTLSMXsolid race · dashed qualifying · each class's best lap as a share of AS's at the same event (the reference class, changeable above); 100% is level, higher is quicker
Event
AS
STL
GTL
SMX
Qual best
Race best
Trap
Qual best
Race best
Trap
vs AS
% of AS
Qual best
Race best
Trap
vs AS
% of AS
Qual best
Race best
Trap
vs AS
% of AS
Atlanta Region SCCA Hoosier Super Tour @ Michelin Raceway Road Atlanta ST26MAR062026-03-06
2:28.404Michael Kamalian · only car+52.937s (+55.45%)
1:34.642Michael Kamalian · only car-0.709s (-0.74%)
140.9Michael Kamalian+2.4 mph (+1.7%)
1:37.000Danny Steyn · fastest of 15 · top 5 within 1.6s+0.012s (+0.01%)
1:36.825Danny Steyn · fastest of 14 · top 5 within 3.2s-0.382s (-0.39%)
126.5Derek Ketchie+6.5 mph (+5.4%)
+2.183squal -51.404s
102.3%qual 65.4%
1:38.517Jarrett Jones · fastest of 20 · top 5 within 0.7s-0.145s (-0.15%)
1:24.667Tyler Gonzales · fastest of 21 · top 5 within 15.4s-14.098s (-14.27%)
120.7Elivan Goulart+3.7 mph (+3.2%)
-9.975squal -49.887s
89.5%qual 66.4%
19 rule changes (AS: 11, STL: 3, GTL: 1, SMX: 4)4 weight · 2 cars added · 2 induction · 11 wording · AS class Spec Lines reorganized for 2026; old table format with chassis, engine, weight, tire, and brake data deleted and moved to main rules and build sheets. · GT3U class removed from GCR; GT3U cars now run in STU with 3.0" main frame and 2" front spoiler minimum ride height. · AS Chevy LS adds Edelbrock Performer RPM 71187 intake manifold with MSD 6014 ignition and 4776 Holly carburetor as spec line option. · AS Ford Mustang Restricted Prep engines lose 3 mm restrictor plate, from 64 mm to 61 mm. · STL minimum weights increase across all classes, 1300 cc gains 195 lbs to 1950, up to 1850 cc at 2500. · AS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft. · AS Cadillac CTS-V 04-07 Restricted Prep weight reduced 50 lbs to 3400. · STL/STU Lotus weight reduced: Evora GT4 to 2700 lbs, Elise Cup R to 2250 lbs, Elise/Exige SC to 2450-2550 lbs. · AS Ford Mustang GT 5.0 2018- weight reduced from 3600 to 3525 lbs. · AS Ford Mustang GT 05-14 Restricted Prep Engine gains alternative gear ratios: 3.66, 2.43, 1.69, 1.32, 1.00, .65 · SMX drivers must submit data acquisition files on time or face suspension and $250 fine. · SMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fine; level 2 and 4 may carry $500 fine. · AS Ford Mustang GT 5.0L (15-17) flat plate restrictor reduced from 67mm to 64mm. · AS LS1/LS6 5.3L truck engine gains four approved intake part numbers: 12561269, 88894095, 89017363, 89017364. · SMX Toyo RR P235/40/ZR17 tire rules clarified: one set per weekend, marking after first session, damage replacement procedures revised. · SMX data submission deadline extended from 30 to 60 minutes after each timed session. · STL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1 instead of 2500 lbs; spec components removed, only alternative tires allowed. · AS Flotek Head plunge cut dimensions figure updated in GCR Section 9.1.6. · AS class notes cleanup: multiple Camaro, Firebird, CTS-V, Challenger, Mustang specs and fuel cell/ECM/head restrictions removed.showhide
AS Re-Organization of AS Spec lines for 2026 #39887wordingwordingAS class Spec Lines reorganized for 2026; old table format with chassis, engine, weight, tire, and brake data deleted and moved to main rules and build sheets.
GTL Remove GT3U from GCR as it is now in STU #39862cars addedcars addedGT3U class removed from GCR; GT3U cars now run in STU with 3.0" main frame and 2" front spoiler minimum ride height.
AS Edelbrock manifold (& timing kit) to Chevy LS Spec Lines Request #39055cars addedcars addedAS Chevy LS adds Edelbrock Performer RPM 71187 intake manifold with MSD 6014 ignition and 4776 Holly carburetor as spec line option.
AS Restrictor Plate Change for Gen 2 Ford Coyote Engine #39501inductionslowerAS Ford Mustang Restricted Prep engines lose 3 mm restrictor plate, from 64 mm to 61 mm.
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.
AS 1994 Mustang Spec Line Request #39104wordingunclearAS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft.
AS Cadillac CTS-V BOP Weight Change #38640weight -50 lbsfasterAS Cadillac CTS-V 04-07 Restricted Prep weight reduced 50 lbs to 3400.
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.
AS RE: Previous Letter 37695 Update #38245weight -75 lbsfasterAS Ford Mustang GT 5.0 2018- weight reduced from 3600 to 3525 lbs.
AS Errors and Omissions #38234wordingwordingAS Ford Mustang GT 05-14 Restricted Prep Engine gains alternative gear ratios: 3.66, 2.43, 1.69, 1.32, 1.00, .65
SMX SMX Data Submission - Penalties #38248wordingwordingSMX drivers must submit data acquisition files on time or face suspension and $250 fine.
SMX Committee) SMX Penaly Clarification updated language #38337wordingwordingSMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fine; level 2 and 4 may carry $500 fine.
AS Errors and Omission #38055inductionslowerAS Ford Mustang GT 5.0L (15-17) flat plate restrictor reduced from 67mm to 64mm.
AS Request to Add LS1/LS6 Intakes for 5.3L Truck Engine EnO #38197wordingwordingAS LS1/LS6 5.3L truck engine gains four approved intake part numbers: 12561269, 88894095, 89017363, 89017364.
SMX Clarify Tire Marking Regs #38004wordingwordingSMX Toyo RR P235/40/ZR17 tire rules clarified: one set per weekend, marking after first session, damage replacement procedures revised.
SMX SMX Data Submission Timeframe #38039wordingwordingSMX data submission deadline extended from 30 to 60 minutes after each timed session.
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.
AS Flotek Head Plunge Cut Inconsistencies #37502wordingunclearAS Flotek Head plunge cut dimensions figure updated in GCR Section 9.1.6.
AS Notes clean up #37693wordingwordingAS class notes cleanup: multiple Camaro, Firebird, CTS-V, Challenger, Mustang specs and fuel cell/ECM/head restrictions removed.
Atlanta Region SCCA Hoosier Super Tour @ Michelin Raceway Road Atlanta ST25MAR072025-03-07
1:35.467Thomas J Ellis · fastest of 4 · top 4 within 2.7s-8.834s (-8.47%)
1:35.351Thomas J Ellis · fastest of 4 · top 4 within 1.1s-24.914s (-20.72%)
138.6James Jost+8.6 mph (+6.6%)
1:36.988Mike Taylor · fastest of 13 · top 5 within 2.0s+0.632s (+0.66%)
1:37.207Mike Taylor · fastest of 11 · top 5 within 1.3s+0.354s (+0.37%)
120.1Derek Ketchie+1.7 mph (+1.5%)
+1.856squal +1.521s
101.9%qual 101.6%
1:38.662Camden Gruber · fastest of 30 · top 5 within 0.2s-0.302s (-0.31%)
1:38.765Skyler Cottrell · fastest of 30 · top 5 within 0.5s-1.159s (-1.16%)
117.0Cam Ebben+1.0 mph (+0.9%)
+3.414squal +3.195s
103.6%qual 103.3%
27 rule changes (AS: 12, STL: 1, GTL: 9, SMX: 5)6 cars added · 2 engine · 2 induction · 2 weight · 1 tyres & wheels · 13 wording · 1 other · AS Spec Lines removes ECM flexibility restriction from five Cadillac and Chevrolet/Pontiac V8 models. · AS Ford Mustang Coyote engines increase restrictor to 80mm from 64mm or 67mm. · AS Mustang GT 05-14 4.6L loses 300 lbs; 15-17 and 2018+ models lose 61mm and 60mm restrictors respectively. · AS class gear ratio options specified for multiple American muscle cars, including Cadillac CTS-V, Chevrolet Camaro, Ford Mustang, Dodge Challenger, and Pontiac GTO. · AS LS-engine cars gain ECU freedom; Camaro/Firebird 93-02 LS1 removes fuel cell location restriction. · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof requirement. · SMX allows OE instrument cluster relocation for aftermarket dash mounting, with wiring re-routed only; alternate gauges now permitted. · STL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval. · GTL Toyota G16E-GTS removes direct injection ban wording, effective 11/1/2024. · GTL Nissan L16 limited prep gains alternate 32mm choke option at 1910 lbs minimum weight. · AS Ford Mustang GT models gain alternate transmission ratio options for 2024-09-01. · GTL adds Toyota GR86 2021-2023, 2dr RWD, 101.3 in wheelbase. · GTL adds Spec Miata 1990-2005 with legal Spec Miata engine and intake system. · Mazda MX5 RF 2017- added to GTL with 91.0 inch wheelbase. · SMX Spec MX-5 camera requirement wording changed; non-functioning recorder now grounds for penalty or disqualification. · SMX Spec MX-5 must run latest AIM Data Logger Spec MX-5 ECU Protocol; wording clarification for technical compliance. · SMX Mazda Miata OE versus OEM definitions clarified in GCR Section 9.1.7.1. · SM and SMX shifter bushing rules clarified: alternate bushing at shift lever bottom now allowed. · GTL added to GT3 choke option line for induction control. · AS Ford Mustang GT 5.0L (2018-) classified at 3600 lbs with 60mm restrictor, Brembo BBK permitted. · AS Chevrolet Camaro 1LE (2016-) classified with 3600 lbs minimum weight, 60mm restrictor, 275 tires. · AS Chevrolet/Pontiac Camaro & Firebird 82-92 5.7L LS1 classified at 3200 lbs with 65mm restrictor plate required. · AS Chevrolet Camaro, Firebird, and Ford Mustang models permitted to use Flo Tek cylinder heads. · GT2-ST Acura NSX minimum weight raised to 3000 lbs, restrictor increased to 45mm TIR. · GTL Datsun 510 L16 Limited Prep allows 34 mm chokes, minimum weight rises to 2000 lbs. · AS Camaro/Firebird and GTO LS1 connecting rods approved: Callies CSC6100DS6A2AH, Scat 2-1CR6100-944, GM 12649190. · AS Cadillac CTS-V, Chevrolet Camaro SS, Dodge Challenger, Ford Mustang GT, Pontiac GTO allowed 11" wheels until 3/1/25.showhide
AS Race memo #37902wordingunclearAS Spec Lines removes ECM flexibility restriction from five Cadillac and Chevrolet/Pontiac V8 models.
AS Increase Coyote Engine Restrictor to 80mm #36177inductionfasterAS Ford Mustang Coyote engines increase restrictor to 80mm from 64mm or 67mm.
AS Performance Pack for 2015+ Mustang #36867enginefasterAS Mustang GT 05-14 4.6L loses 300 lbs; 15-17 and 2018+ models lose 61mm and 60mm restrictors respectively.
AS Gear Ratios #37131wordingwordingAS class gear ratio options specified for multiple American muscle cars, including Cadillac CTS-V, Chevrolet Camaro, Ford Mustang, Dodge Challenger, and Pontiac GTO.
AS ECU specs for LS engine #37208enginefasterAS LS-engine cars gain ECU freedom; Camaro/Firebird 93-02 LS1 removes fuel cell location restriction.
GTL Correct language regarding OEM Areo Devices #37137wordingwordingTA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof requirement.
SMX E&O SMX Regs 9.1.7.1.D.5.u-.w #37070wordingwordingSMX allows OE instrument cluster relocation for aftermarket dash mounting, with wiring re-routed only; alternate gauges now permitted.
STL Request to Remove Miata Hubs from General category #37138wordingwordingSTL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval.
GTL G16E-GTS Fuel Injection Spec Line Change #36588wordingunclearGTL Toyota G16E-GTS removes direct injection ban wording, effective 11/1/2024.
GTL GTL Alternate Weight and Choke Option for L16 engine #36653inductionfasterGTL Nissan L16 limited prep gains alternate 32mm choke option at 1910 lbs minimum weight.
AS Mustang transmission ratios #36662wordingunclearAS Ford Mustang GT models gain alternate transmission ratio options for 2024-09-01.
GTL Request to Include Toyota GR86 in GTL #36324cars addedcars addedGTL adds Toyota GR86 2021-2023, 2dr RWD, 101.3 in wheelbase.
GTL Inclusion of Modified Spec Miata for GTL competition #36325cars addedcars addedGTL adds Spec Miata 1990-2005 with legal Spec Miata engine and intake system.
GTL Include Mazda MX5 RF 2017- in GTL #36428cars addedcars addedMazda MX5 RF 2017- added to GTL with 91.0 inch wheelbase.
SMX SMX Camera Rule Correction #36496wordingwordingSMX Spec MX-5 camera requirement wording changed; non-functioning recorder now grounds for penalty or disqualification.
SMX Committee) AIM ECU Protocol #36556wordingwordingSMX Spec MX-5 must run latest AIM Data Logger Spec MX-5 ECU Protocol; wording clarification for technical compliance.
SMX Committee) OE versus OEM Definitons #36608wordingwordingSMX Mazda Miata OE versus OEM definitions clarified in GCR Section 9.1.7.1.
SMX Committee) Shifter Bushing #36611wordingwordingSM and SMX shifter bushing rules clarified: alternate bushing at shift lever bottom now allowed.
GTL Add GTL to GT3 choke option line. #36236wordingunclearGTL added to GT3 choke option line for induction control.
AS Request for Classification of 2018-2023 mustang In #35764cars addedcars addedAS Ford Mustang GT 5.0L (2018-) classified at 3600 lbs with 60mm restrictor, Brembo BBK permitted.
AS 6th gen Camaro limited prep #35733cars addedcars addedAS Chevrolet Camaro 1LE (2016-) classified with 3600 lbs minimum weight, 60mm restrictor, 275 tires.
AS Chevrolet/Pontiac Camaro & Firebird (82-92) 5.7L V8 LS1 Alum BLK #35825cars addedcars addedAS Chevrolet/Pontiac Camaro & Firebird 82-92 5.7L LS1 classified at 3200 lbs with 65mm restrictor plate required.
AS Full Prep Head #35891otherotherAS Chevrolet Camaro, Firebird, and Ford Mustang models permitted to use Flo Tek cylinder heads.
GTL Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslowerGT2-ST Acura NSX minimum weight raised to 3000 lbs, restrictor increased to 45mm TIR.
GTL Allow 34 mm chokes for the Datsun 510 #35661weight +50 lbsslowerGTL Datsun 510 L16 Limited Prep allows 34 mm chokes, minimum weight rises to 2000 lbs.
AS Restricted Prep Aftermarket Parts Request #35682wordingwordingAS Camaro/Firebird and GTO LS1 connecting rods approved: Callies CSC6100DS6A2AH, Scat 2-1CR6100-944, GM 12649190.
AS Allowance of 11 #35824tyres & wheelsfasterAS Cadillac CTS-V, Chevrolet Camaro SS, Dodge Challenger, Ford Mustang GT, Pontiac GTO allowed 11" wheels until 3/1/25.
Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST24MAR082024-03-08
1:44.301Phillip Waters · only car+7.955s (+8.26%)
2:00.265Phillip Waters · only car+24.272s (+25.29%)
130.0Phillip Waters-13.7 mph (-9.5%)
1:36.356Danny Steyn · fastest of 15 · top 5 within 3.3s-0.113s (-0.12%)
1:36.853Danny Steyn · fastest of 17 · top 5 within 2.8s+1.641s (+1.72%)
118.3Mike Taylor-8.8 mph (-6.9%)
-23.412squal -7.945s
80.5%qual 92.4%
1:38.327Chris Bovis · fastest of 5 · top 5 within 8.7s-10.718s (-9.83%)
1:36.868Chris Bovis · fastest of 5 · top 5 within 10.5s-12.160s (-11.15%)
118.0Peter Shadowen+14.0 mph (+13.4%)
-23.397squal -5.974s
80.5%qual 94.3%
1:38.964Michael Tinis · fastest of 33 · top 5 within 0.5s
1:39.924Will Robusto · fastest of 33 · top 5 within 1.1s
116.0Jack Murchison
-20.341squal -5.337s
83.1%qual 94.9%
24 rule changes (AS: 8, STL: 5, GTL: 11)6 cars added · 3 induction · 2 engine · 2 weight · 1 aero · 1 tyres & wheels · 9 wording · Chevrolet Camaro, Pontiac Firebird 70-81 Full Prep classified AS at 3400-3600 lbs with 250 lb weight reduction. · AS class: multiple cars gain fuel cell placement note allowing 24 inches from standard tank, unrestricted filler location. · Chevrolet Camaro 16- Full Prep classified into AS at 3400 lbs with 250 lb weight reduction. · AS adds Ford Mustang GT 05-14 Restricted prep Engine with 62mm FPR, 3400 lbs minimum, 18-inch wheels. · GT1, GT2, GT3, GTL, GTX rear spoiler maximum surface area limit of 295.0 square inches removed. · GT1/GT2/GT3/GTL/GTX Direct Injection now permitted if OE, using only OE pump, hoses, injectors. · GT2/3 Nissan, Mazda, Mitsubishi 4G93, QR25DE/DD, QE25DE/DD Direct Injection now permitted per 9.1.2.F.7.5.E. · 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. · GTL Mazda 12A rotary engines may machine and use 13B housing to O.E. 12A specifications. · GTL Toyota GR86 (DR86, 2021-2024, 2-door RWD, 101.3-inch wheelbase) newly classified. · GTL BMW Mini years corrected to 2002-2013. · 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. · GTL small unrestricted engines under 1399cc lose 40-50 lbs across Alfa, AMC, Triumph, Mini, Sprite, Fiat, Ford, Honda, Mazda, Nissan, Subaru, Toyota, Volkswagen. · GTL Honda Fit 2009-13 2-door FWD classified with wheelbase options 94.0, 97.0, or 99.0 inches. · GTL spec lines moved to contiguous position with GT2 and GT3; GTA category and spec lines renumbered and moved behind GTL. · GTL Nissan Sentra/200SX A14 engine weight reduced from 1850 lbs to 1800 lbs. · AS crate motor part number specified: GM Performance CT400 P/N 19370604 engine assembly for GM vehicles. · AS Spec Lines Ford Mustang GT 5.0L (15-17) max wheel size increases to 19.0 inches. · AS Dodge Challenger 5.7L/6.1L/6.4L V8 now permits SPC-66045 alternate front upper control arms. · AS Dodge Challenger 5.7L/6.1L/6.4L V8 allows alternate front brake caliper adapters for updated or backdated components. · STL ITA/ITS RX7 and 1985+ ITA/ITS/ITB/ITC vehicles clarified to conform to section 9.1.4.2 tire specifications. · Fields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight.showhide
AS Request to Classify 1970-1981 Camaro and Firebird in AS #33659cars addedcars addedChevrolet Camaro, Pontiac Firebird 70-81 Full Prep classified AS at 3400-3600 lbs with 250 lb weight reduction.
AS Fuel Cell 12 #34194wordingwordingAS class: multiple cars gain fuel cell placement note allowing 24 inches from standard tank, unrestricted filler location.
AS Please Classify the 6th Gen Into AS. #35448cars addedcars addedChevrolet Camaro 16- Full Prep classified into AS at 3400 lbs with 250 lb weight reduction.
AS spec lines #35713cars addedcars addedAS adds Ford Mustang GT 05-14 Restricted prep Engine with 62mm FPR, 3400 lbs minimum, 18-inch wheels.
GTL Rear Blade Spoiler Clarification #35261aerofasterGT1, GT2, GT3, GTL, GTX rear spoiler maximum surface area limit of 295.0 square inches removed.
GTL GT Direct Injection allowance and rules #35437enginefasterGT1/GT2/GT3/GTL/GTX Direct Injection now permitted if OE, using only OE pump, hoses, injectors.
GTL GT2/3 remove Direction Injection not allowed in Spec line notes #35439inductionfasterGT2/3 Nissan, Mazda, Mitsubishi 4G93, QR25DE/DD, QE25DE/DD Direct Injection now permitted per 9.1.2.F.7.5.E.
STL ST Electric-Assisted Steering Systems #35066wordingwordingSTL 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.
GTL Rotary Engine 12A Rotor Housings #35131wordingwordingGTL Mazda 12A rotary engines may machine and use 13B housing to O.E. 12A specifications.
GTL Request to Include Toyota GR86 in GTL #35198cars addedcars addedGTL Toyota GR86 (DR86, 2021-2024, 2-door RWD, 101.3-inch wheelbase) newly classified.
GTL Errors and Omissions, GTL engines & Cars #35226wordingwordingGTL BMW Mini years corrected to 2002-2013.
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.
GTL Small Engines in GT Lite #34842weightfasterGTL small unrestricted engines under 1399cc lose 40-50 lbs across Alfa, AMC, Triumph, Mini, Sprite, Fiat, Ford, Honda, Mazda, Nissan, Subaru, Toyota, Volkswagen.
GTL Request to Classify Honda Fit body in GTL #35020cars addedcars addedGTL Honda Fit 2009-13 2-door FWD classified with wheelbase options 94.0, 97.0, or 99.0 inches.
GTL Errors in GTCS Headings and Use of the Terms Category and ClassChange existing GTL and GTA Rules #34453wordingwordingGTL spec lines moved to contiguous position with GT2 and GT3; GTA category and spec lines renumbered and moved behind GTL.
GTL Weight for Nissan Sentra/200SX A 1400's #34918weight -50 lbsfasterGTL Nissan Sentra/200SX A14 engine weight reduced from 1850 lbs to 1800 lbs.
AS Crate Motor Part Numbers #32944wordingwordingAS crate motor part number specified: GM Performance CT400 P/N 19370604 engine assembly for GM vehicles.
AS Request wheel size change #33007tyres & wheelsfasterAS Spec Lines Ford Mustang GT 5.0L (15-17) max wheel size increases to 19.0 inches.
AS Alternative Upper Front Control Arms for Dodge Challenger #33352wordingwordingAS Dodge Challenger 5.7L/6.1L/6.4L V8 now permits SPC-66045 alternate front upper control arms.
AS Front Brake Caliper Adapters for Dodge Challenger #33353wordingwordingAS Dodge Challenger 5.7L/6.1L/6.4L V8 allows alternate front brake caliper adapters for updated or backdated components.
STL Clarify STL table B - IT spec notes on Tires #34187wordingwordingSTL ITA/ITS RX7 and 1985+ ITA/ITS/ITB/ITC vehicles clarified to conform to section 9.1.4.2 tire specifications.
GTL Please classify Fields Cardinal V8 #33784cars addedcars addedFields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight.
Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST23MAR102023-03-10
1:36.469Danny Steyn · fastest of 16 · top 5 within 3.9s+0.493s (+0.51%)
1:35.212Danny Steyn · fastest of 17 · top 5 within 3.8s-0.267s (-0.28%)
127.1Mike Taylor+0.7 mph (+0.6%)
1:49.045David Blain · only car+10.780s (+10.97%)
1:49.028David Blain · only car+12.492s (+12.94%)
104.0David Blain-26.3 mph (-20.2%)
11 rule changes (AS: 3, STL: 1, GTL: 7)3 cars added · 2 weight · 1 engine · 1 tyres & wheels · 4 wording · GTL Toyota 3K, 4K, 5K engines now permitted to use 4Y block only. · GT2 Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines newly classified in spec line. · STL Spec MX5 clutch, wheels, and tyres specified: ACT 0000-02-5004-G6, 17x8 wheels, Toyo RR and RA1 235-40-17. · GTL Fiat 1500 Limited Prep X1/9 weight increases to 2000 lbs. · GT2 TA2 and GTA throttle body part numbers updated to GM 90mm electronic #12570790 or Edelbrock 90mm mechanical #33869 or #3870. · Ford Festiva 1988-1993 added to GTL with Mazda B3 1324cc engine. · GTL Toyota G16E-GTS 3-cylinder engine added: 1618cc, 1945 lbs, naturally aspirated with SIR fuel induction. · AS allows Hoosier W2 tyre option in addition to R7, R6, WET/H20. · AS Dodge Challenger 08-20 adds two transmission ratio options: 2.97, 2.10, 1.45, 1.00, 0.74, 0.50 or 2.26, 1.58, 1.19, 1.00, 0.77, 0.63. · GT taillights may now be original style or a panel graphic with functioning red LED brake lamps; wording change only. · AS Cadillac CTS-V 6.0L V8 removes 50 lbs weight penalty for 295 tire size.showhide
GTL Toyota 4Y Engine Classification Request #33562engineengineGTL Toyota 3K, 4K, 5K engines now permitted to use 4Y block only.
GTL Toyota 4A-F and 4A-FE 1.6L DOHC 16V Engine Request #33415cars addedcars addedGT2 Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines newly classified in spec line.
STL Spec MX5 in STL #33473wordingwordingSTL Spec MX5 clutch, wheels, and tyres specified: ACT 0000-02-5004-G6, 17x8 wheels, Toyo RR and RA1 235-40-17.
GTL Fiat HP Limited Prep X1/9 Weight in GTL #33297weightslowerGTL Fiat 1500 Limited Prep X1/9 weight increases to 2000 lbs.
GTL GT2 (TA2)/GTA Part Number Update #33315wordingwordingGT2 TA2 and GTA throttle body part numbers updated to GM 90mm electronic #12570790 or Edelbrock 90mm mechanical #33869 or #3870.
GTL Request to add Ford Festiva to GTL #33335cars addedcars addedFord Festiva 1988-1993 added to GTL with Mazda B3 1324cc engine.
GTL Engine Request #33064cars addedcars addedGTL Toyota G16E-GTS 3-cylinder engine added: 1618cc, 1945 lbs, naturally aspirated with SIR fuel induction.
AS Request to add Hoosier W2 #33031tyres & wheelstyres & wheelsAS allows Hoosier W2 tyre option in addition to R7, R6, WET/H20.
AS correction of Dodge Challenger specification line #33151wordingwordingAS Dodge Challenger 08-20 adds two transmission ratio options: 2.97, 2.10, 1.45, 1.00, 0.74, 0.50 or 2.26, 1.58, 1.19, 1.00, 0.77, 0.63.
GTL Tail lights on all GT category race cars. #32799wordingwordingGT taillights may now be original style or a panel graphic with functioning red LED brake lamps; wording change only.
AS Request CTS-V Spec Line Error Correction #30242weightfasterAS Cadillac CTS-V 6.0L V8 removes 50 lbs weight penalty for 295 tire size.
Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST22MAR122022-03-12
1:36.346Gregory Eaton · fastest of 3 · top 3 within 7.0s
1:35.993Gregory Eaton · fastest of 2
143.6Gregory Eaton
1:35.976Danny Steyn · fastest of 18 · top 5 within 2.9s
1:35.479Danny Steyn · fastest of 18 · top 5 within 3.2s
126.3Trever Degioanni
-0.514squal -0.370s
99.5%qual 99.6%
1:38.265Peter Shadowen · fastest of 2
1:36.536Peter Shadowen · fastest of 2
130.3Peter Shadowen
+0.543squal +1.919s
100.6%qual 102.0%
122 earlier rule changes on record, in force before Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta (from 2019)23 cars added · 15 induction · 15 weight · 8 engine · 7 aero · 4 suspension & brakes · 3 tyres & wheels · 1 removed · 45 wording · 1 other · Ginetta G40 classified in GTL with Ford Zetec 1796cc engine at 2050 lbs, plus 51 lbs for IRS or 26 lbs for sequential. · 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. · SMG long tube headers: Borla PN 17237 discontinued, Kooks PN 11312000 and American Racing PN MT3-05134300LSNC approved alternatives. · AS Mercury Capri (79-86) removed as individual spec line, merged into Ford Mustang (79-93) spec line. · AS Spec Mustang SMG loses 3.73 gear ratio and 355/300 mm brake specification. · AS Chevrolet, Pontiac, Ford full prep engines now permit alternate cylinder heads with restrictor plate ALL26180 and 1.250 inserts ALL26186 for regional competition. · 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. · AS Chevrolet/Pontiac Camaro & Firebird 93-02 now allow BMR AA004 or UMI 2310 adjustable front upper control arms. · AS Pontiac GTO 04-06 LS1 to 3300 lbs, LS2 to 3350 lbs on 295 tire. · GT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight. · STL Spec MX-5 removes redundant specification line; no performance change. · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two sections and 6010 to 6014X in TA2 Appendix. · GTL Honda B18a,b vs B18c: new split classifies B18a,b at 2050 lbs, B18c at 2065 lbs. · GTL Nissan B13 Sentra allowed hood bulge maximum 1.5 inches high, 10.0 inches long, 6.0 inches wide. · GTL BMW E21 added to GT Cars - BMW classification. · AS Cadillac CTS-V 6.0L V8 removes 50 lbs tire size penalty, making it lighter. · AS consolidates seven SN95 Mustang spec lines into three: 94-04 including Cobra, 94-95 5.0/5.8, and 96-04 4.6L two/four valve. · AS Camaro/Firebird LT1/LS1 transmission code changes to 6362; Mustang GT 4.6L/5spd changes to 5.0L/6spd with 300 lbs weight reduction. · AS Camaro/Firebird and Mustang GT gear ratio specifications restored with alternate sets permitted. · AS Chevrolet Camaro & Firebird, Ford Mustang variants, Mercury Capri minimum weights increase 50 lbs across all model years. · STL Volkswagen 2.0L TFSI 1984cc classified with turbocharger removal required, meeting all other STL specs. · 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. · ST oil coolers and filters now explicitly allowed to be added or substituted; wording clarifies existing permissions. · AS Mustang 4.6L/5spd loses 300 lbs; 5.0L/6spd gains 56mm restrictor requirement. · AS CTS-V LS6 and LS2 may now use Driveshaft Shop carbon fiber driveshaft for durability. · AS Chevrolet Camaro SS V8 6.2L model years extended from 10-13 to 10-15. · GTL Mazda 12A SIR increases to 29mm, minimum weight rises to 2000 lbs. · 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. · Fiat X-1/9 Bertone 1500 added to GTL with 2000 lbs minimum weight, SOHC, fuel induction options, Level 2 prep. · 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. · Ford Mustang GT 5.0L 15-17 Restricted Preparation classified in AS with 55mm flat plate restrictor required. · AS underhood bracing on stock hoods, trunks, and rear decks may be modified or removed. · AS Cadillac CTS-V 04-07 with 295 tire drops to 3450 lbs; Camaro SS V8 10-13 275 tire removed; Challenger 08-20 gains 315 tire option at 3600 lbs. · AS Camaro & Firebird (93-02) and Mustang GT (05-14) specifications restored with 200 lb weight reduction for permitted heads. · GTL Nissan MRA8DE 1797cc engine classified with 2050 lbs minimum weight and 22.5mm restrictor. · GTL Mazda 13B SIR increases from 26mm to 28mm; 27mm plus 175 lbs option removed. · 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. · AS Dodge Challenger 08-20 gains 6.1L and 6.4L V8 options; 5.7L weight rises to 3500 lbs on 295 tyres, 3600 on 315 tyres. · AS Camaro/Firebird (93-02) and Mustang Coupe GT (05-14) consolidated into single specs with 100 lb and 300 lb weight reductions respectively. · ST aero devices and reference areas now include end plates but exclude fasteners protruding over 1/2 inch. · GT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line. · AS Dodge Challenger 5.7L V8 gets iron block requirement, 10.5:1 compression max, intake valve 12.7 mm, exhaust 12.3 mm, intake duration 188°, exhaust duration 205°. · AS Dodge Challenger 08-14 rear spoiler part number changes from 1GL20RXF to 1GL20TZZAB. · GTL Mazda 13B restrictor increases to 26mm SIR, minimum weight rises to 2125 lbs. · 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. · AS class pursues specified list of eligible tires; details of tire changes not provided in letter. · AS class pursuing specified list of eligible tires; details pending further communication. · No restrictor plate change implemented; 2021 AS Mustang Coyote under evaluation. · AS 2005-2009 Restricted Prep 4.6 3V now permits conversion to 2 valve configuration. · AS Ford Mustang Coupe GT 4.6L 3V Restricted Prep now permits Ford Performance camshaft kit P/N-M-6550-3V. · 2010-2014 Camaro reclassified to AS; full preparation classification approved effective 2020-07-01. · AS class cylinder head replacement options under review; implementation planned for 2021 season. · AS Mustang, Camaro, Firebird, Capri max brake rotor diameter increases from 12.2 to 13.1 inches. · AS rotor diameter increase approved; see Fastrack letter #28748 for details. · GTL Toyota MR2 Spyder 1999-2007 newly classified. · TA2 Gurney flap wording clarified: terminology standardized to 'Gurney flap', height limits and thickness specifications remain 0.50 inch / 0.625 inch or 0.375 inch / 0.0625 inch depending on configuration. · STO rear wing wording clarified: 'wicker' changed to 'Gurney flap' in maximum chord and mounting height rules. · GT classes clarify Gurney flap wording, replacing wickerbill/tab terminology with flap; specifications unchanged. · GTL Mazda 13B restrictor size clarification issued; refer to letter 28518 for details. · GT3 and STU add Borg-Warner EFR6258 to approved turbocharger list. · GTL stall test procedure clarified: intake system must pass SIR test as raced, no air bypass allowed. · 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. · AS Chevrolet/Pontiac Camaro & Firebird (82-92) loses 50 lbs, to 3500. · GTL wing mount openings excluded from square inch limit. · STL Honda B18 restrictor reduced from 54mm to 53mm flat plate; B18C1 added with 54mm restrictor. · 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. · GTL wing mounting posts limited to 85 square inches exposed area each, measured flat from side view. · GTL wing mounting posts limited to 85 square inches exposed area each, measured flat from side. · GTL wing endplates change from 8.5×3.0 inch rectangle to maximum 64 square inches. · GTL Mazda 12A Street Port minimum weight reduced to 1950 lbs from 2000 lbs. · STL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL. · AS rear trailing arms may be replaced with tubular arms maintaining stock length and axle location purpose only. · AS Ford and GM full-prep cars get 200 lb weight reduction, up from 150 lb. · 05-10 Ford Mustang Coupe GT 4.6L OHC classified AS with 3200 lbs minimum weight, HR cam restricted prep. · AS 10-15 Chevrolet Camaro Full Prep classified with 3400 lbs base weight, over 313 CID engine 3700 lbs maximum. · GT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications. · Factory Five Type 65 Coupe R with Ford 302/351 or 5.0/5.2L NA added to GTX-MISC at 2600 lbs. · GTL adds Jetta Mk1 two door classification effective 2020-01-01. · GTL Honda CRX 84-87 and 88-91 remove IRS option with 2.5% weight penalty. · AS Spec Mustang (SMG) added as Restricted Prep class. · Mazda Spec MX-5 Challenge classified in STL with 2000cc displacement and 2500 lbs minimum weight. · GTL Fun Cup Beetle engine weight specified at 1850 lbs with sealed SOHC 1780cc specification. · AS class minimum ride height clarified to 5 inches measured at rocker panel, excluding seams and cladding. · GTL Fun Cup Beetle removes reference to VW engine table; Fun Cup engine spec remains 1.8L at 2040 lbs. · GTL Honda CRZ 10-14, CRZ 15-16, and Insight 00-06 gain alternate wheelbase option of 90.6 in. · STU alternate intake manifolds now allowed case-by-case instead of prohibited. · AS Ford Mustang (79-93) 313 CID and under loses 100 lbs to 3150; over 313 CID loses 100 lbs to 3450. · STL Acura/Honda B18 except C engine restrictor increases from 53mm to 54mm flat plate. · GTL adds VW Fun Cup Beetle, all model years, 2-door RWD, 94.5-inch wheelbase. · GTX tube frame cars gain fuel injection with 90mm maximum throttle body size. · Ligier JS2 R classified in GTX, no performance parameters specified in filing. · GTL Mazda 13B may use 25mm SIR with 175 lbs weight penalty added. · STL and STU ride height measurement clarified: without driver, at rocker panel lowest point, excluding pinch weld. · GT1 and GT2/GT3/LITE ride height requirements removed from GCR sections 9.1.2.D.5.a.1 and 9.1.2.F.7.b. · GTL Mazda 12A may use 28mm SIR plus 175 lbs. · GTL Mustang 94-04 newly classified in GTL. · 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. · AS Spec Mustang (SMG) newly classified with 107.1 wheelbase, 3.73 gears, 355mm front brakes, 300mm rear. · GTL Mini 1275-1399 Iron and Aluminum Crossflow gain 75 lbs weight reduction to 125 lbs with OE common sump gearbox. · GTL BMC thru Rover Group removes long inactive Mini engines: 948, 970, 1071, 1098. · GTX FIA GT3: Audi R8 40mm restrictor 2900 lbs, BMW Z4 70mm 2800 lbs, Ferrari 488 35mm restrictor 3025 lbs classified. · 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.showhide
GTL Request to Classify Ginetta G40 in GTL #31599cars addedcars addedGinetta G40 classified in GTL with Ford Zetec 1796cc engine at 2050 lbs, plus 51 lbs for IRS or 26 lbs for sequential.
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 & wheelstyres & wheelsSTL and STU Improved Touring vehicles must conform to 9.1.4 Tires & Wheels requirements.
AS Proposed Revisions to SCCA GCR 2021 Appendix M, Part 3 #30295wordingwordingSMG long tube headers: Borla PN 17237 discontinued, Kooks PN 11312000 and American Racing PN MT3-05134300LSNC approved alternatives.
AS specification line consolidation and correction #31846wordingwordingAS Mercury Capri (79-86) removed as individual spec line, merged into Ford Mustang (79-93) spec line.
AS correction of SMG specification line #31847wordingunclearAS Spec Mustang SMG loses 3.73 gear ratio and 355/300 mm brake specification.
AS Alternate cylinder heads for full prep engine builds - Evaluation #31851engineunclearAS Chevrolet, Pontiac, Ford full prep engines now permit alternate cylinder heads with restrictor plate ALL26180 and 1.250 inserts ALL26186 for regional competition.
STL Throttling Device Clarification #31323wordingwordingSTL 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 #31621wordingwordingSTL Mazda RX-7 12A 79-85 clarifies carburetor, emissions, and water jacket modification rules.
AS Request for adjustable Front Upper Control Arms on 4th Gen F-Body #30457suspension & brakessuspension & brakesAS Chevrolet/Pontiac Camaro & Firebird 93-02 now allow BMR AA004 or UMI 2310 adjustable front upper control arms.
AS Request Pontiac GTO tire size change #30881weightslowerAS Pontiac GTO 04-06 LS1 to 3300 lbs, LS2 to 3350 lbs on 295 tire.
GTL Request car classification #31032cars addedcars addedGT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight.
STL Request to clean up Spec MX-5 Redundancy #31069wordingwordingSTL Spec MX-5 removes redundant specification line; no performance change.
GTL Request to Update GTA Obsolete Part Numbers #30615wordingwordingGTA part numbers updated: 0-80541-1 to 0-80541-2 in two sections and 6010 to 6014X in TA2 Appendix.
GTL Request clarification for the Honda B18a,bVS B18c #30482wordingwordingGTL Honda B18a,b vs B18c: new split classifies B18a,b at 2050 lbs, B18c at 2065 lbs.
GTL Request to Allow Hood Bulge on Nissan B13 Sentra #30504aeroaeroGTL Nissan B13 Sentra allowed hood bulge maximum 1.5 inches high, 10.0 inches long, 6.0 inches wide.
GTL Request BMW E21 Classing #30582cars addedcars addedGTL BMW E21 added to GT Cars - BMW classification.
AS Request CTS-V Spec Line Error Correction #30242weightfasterAS Cadillac CTS-V 6.0L V8 removes 50 lbs tire size penalty, making it lighter.
AS Request to consolidate SN95 Mustang '94-'04 Mustang spec lines #30428wordingwordingAS consolidates seven SN95 Mustang spec lines into three: 94-04 including Cobra, 94-95 5.0/5.8, and 96-04 4.6L two/four valve.
AS American Sedan Transmission Rule Change Request #30595enginefasterAS Camaro/Firebird LT1/LS1 transmission code changes to 6362; Mustang GT 4.6L/5spd changes to 5.0L/6spd with 300 lbs weight reduction.
AS Correction to specifications inadvertently deleted #30691wordingwordingAS Camaro/Firebird and Mustang GT gear ratio specifications restored with alternate sets permitted.
AS weight adjustments #30700weight +50 lbsslowerAS Chevrolet Camaro & Firebird, Ford Mustang variants, Mercury Capri minimum weights increase 50 lbs across all model years.
STL VW Engine Request #30625engineslowerSTL Volkswagen 2.0L TFSI 1984cc classified with turbocharger removal required, meeting all other STL specs.
STL Request Mazda B5 DOHC #30420cars addedcars addedSTL 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.
STL ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wordingwordingST oil coolers and filters now explicitly allowed to be added or substituted; wording clarifies existing permissions.
AS AS Mustang LP 4.6 3V Classification Transmission Request #29886weightfasterAS Mustang 4.6L/5spd loses 300 lbs; 5.0L/6spd gains 56mm restrictor requirement.
AS Request CF driveshaft on CTS-V for durability improvement #30117otherotherAS CTS-V LS6 and LS2 may now use Driveshaft Shop carbon fiber driveshaft for durability.
AS Adjustment to model years of 5th generation RP Camaro #30348wordingwordingAS Chevrolet Camaro SS V8 6.2L model years extended from 10-13 to 10-15.
GTL Request for Help for Mazda 12A #29754induction +50 lbsslowerGTL Mazda 12A SIR increases to 29mm, minimum weight rises to 2000 lbs.
STL GM Ecotec engines in STL #30247wordingwordingSTL GM Ecotec engines now permit any combination within the family, must use 55mm flat plate restrictor.
STL Super Touring Alternate Miata Hubs #30345wordingwordingSTL/STU 90-05 Mazda Miata gains approval for Mazda Motorsports Development alternate front wheel hubs.
GTL Request LP HP Fiat X1/9 & Bertone 1500 to GTL #30058cars addedcars addedFiat X-1/9 Bertone 1500 added to GTL with 2000 lbs minimum weight, SOHC, fuel induction options, Level 2 prep.
STL Brake Component Relocation #29990wordingwordingST cars may relocate ABS actuation hardware and wiring anywhere in engine compartment.
STL Super Touring Wing Clarification #30111aeroaeroSTL rear wing trailing edge, including end plates and gurney flap, maximum rearward mounting clarified to center of rearmost bodywork.
STL Transmission Options #30118wordingwordingSTL allows OEM gear sets from same manufacturer transmissions with input shaft modifications for fitment.
AS Request for 2015 -2017 Ford Mustang Spec Line #29514cars addedcars addedFord Mustang GT 5.0L 15-17 Restricted Preparation classified in AS with 55mm flat plate restrictor required.
AS Request Trunk lid / Rear Hatch clarification #29591wordingwordingAS underhood bracing on stock hoods, trunks, and rear decks may be modified or removed.
AS Common Weight for CTS-V Tire #29759weightfasterAS Cadillac CTS-V 04-07 with 295 tire drops to 3450 lbs; Camaro SS V8 10-13 275 tire removed; Challenger 08-20 gains 315 tire option at 3600 lbs.
AS Correction to specifications inadvertently deleted #30041weightfasterAS Camaro & Firebird (93-02) and Mustang GT (05-14) specifications restored with 200 lb weight reduction for permitted heads.
GTL Increase 13b SIR size #29867inductionfasterGTL Mazda 13B SIR increases from 26mm to 28mm; 27mm plus 175 lbs option removed.
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.
AS Request Additional Engine Options for Dodge Challenger Spec Line #29543engineslowerAS Dodge Challenger 08-20 gains 6.1L and 6.4L V8 options; 5.7L weight rises to 3500 lbs on 295 tyres, 3600 on 315 tyres.
AS Rule simplification spec line communization #29824wordingfasterAS Camaro/Firebird (93-02) and Mustang Coupe GT (05-14) consolidated into single specs with 100 lb and 300 lb weight reductions respectively.
STL Request clarification on wing measurement #29640aeroaeroST aero devices and reference areas now include end plates but exclude fasteners protruding over 1/2 inch.
GTL GT Category Wording #29193wordingunclearGT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line.
AS Dodge Challenger AS Spec Line Clarification #28698engineslowerAS Dodge Challenger 5.7L V8 gets iron block requirement, 10.5:1 compression max, intake valve 12.7 mm, exhaust 12.3 mm, intake duration 188°, exhaust duration 205°.
AS Dodge Challenger AS Spec Line Clarification #2 #28699wordingwordingAS Dodge Challenger 08-14 rear spoiler part number changes from 1GL20RXF to 1GL20TZZAB.
GTL Request to change the Mazda 13b restrictor size #28518induction +175 lbsfasterGTL Mazda 13B restrictor increases to 26mm SIR, minimum weight rises to 2125 lbs.
STL Minimum Weight Determination #27695wordingwordingSTL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis adjustments.
STL ST Gurney flap Wicker clarification #29012wordingwordingSTL and STU rear wing rules clarify that wicker is a Gurney flap; no performance change.
AS Support for R-Type Specification Tires #27450tyres & wheelsunclearAS class pursues specified list of eligible tires; details of tire changes not provided in letter.
AS Spec Tire Request #27519tyres & wheelsunclearAS class pursuing specified list of eligible tires; details pending further communication.
AS Restrictor Plate Change for RP 2011+ Mustang with Coyote Engine #27675wordingunclearNo restrictor plate change implemented; 2021 AS Mustang Coyote under evaluation.
AS 2005-2009 Restricted Prep 4.6 3V #27908engineunclearAS 2005-2009 Restricted Prep 4.6 3V now permits conversion to 2 valve configuration.
AS Request for 2005-2009 Restricted Prep 4.6 3V Parts #27909wordingunclearAS Ford Mustang Coupe GT 4.6L 3V Restricted Prep now permits Ford Performance camshaft kit P/N-M-6550-3V.
AS Request for Full Preparation Classification for 2010-2014 Camaro #28030cars addedunclear2010-2014 Camaro reclassified to AS; full preparation classification approved effective 2020-07-01.
AS Cylinder Heads #28696wordingunclearAS class cylinder head replacement options under review; implementation planned for 2021 season.
AS Request for Max Rotor Diameter Change #28748suspension & brakesfasterAS Mustang, Camaro, Firebird, Capri max brake rotor diameter increases from 12.2 to 13.1 inches.
AS Request increase rotor diameter #28797suspension & brakessuspension & brakesAS rotor diameter increase approved; see Fastrack letter #28748 for details.
GTL Request to classify 1999-2007 Toyota MR2 Spyder body #28870cars addedcars addedGTL Toyota MR2 Spyder 1999-2007 newly classified.
GTL TA2 Gurney flap wicker clarification #28874wordingwordingTA2 Gurney flap wording clarified: terminology standardized to 'Gurney flap', height limits and thickness specifications remain 0.50 inch / 0.625 inch or 0.375 inch / 0.0625 inch depending on configuration.
GTL STO Gurney flap wicker clarification #28883wordingwordingSTO rear wing wording clarified: 'wicker' changed to 'Gurney flap' in maximum chord and mounting height rules.
GTL Mazda 13b Restrictor Size Follow up to Letter 28518 #29015wordingunclearGTL Mazda 13B restrictor size clarification issued; refer to letter 28518 for details.
STL Request for Addition to GT3 Approved Turbo List #27576wordingwordingGT3 and STU add Borg-Warner EFR6258 to approved turbocharger list.
GTL Stall Test #28709wordingwordingGTL stall test procedure clarified: intake system must pass SIR test as raced, no air bypass allowed.
STL Request to add 2016-2019 GMX-5 Spec line #28604cars addedcars addedSTL 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.
AS weight adjustments for 2020 season #28785weight -50 lbsfasterAS Chevrolet/Pontiac Camaro & Firebird (82-92) loses 50 lbs, to 3500.
GTL GTL Wing Rule #28754aeroaeroGTL wing mount openings excluded from square inch limit.
STL STL Honda B18 restrictor changes #28794inductionfasterSTL Honda B18 restrictor reduced from 54mm to 53mm flat plate; B18C1 added with 54mm restrictor.
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.
GTL Wing Mounting Upright Size #27641aeroaeroGTL wing mounting posts limited to 85 square inches exposed area each, measured flat from side view.
GTL Wing Mounting Upright Size #27641aeroaeroGTL wing mounting posts limited to 85 square inches exposed area each, measured flat from side.
GTL GTL wing end plates addition #28243aerofasterGTL wing endplates change from 8.5×3.0 inch rectangle to maximum 64 square inches.
GTL Clarification to letter #27406 #28309weight -50 lbsfasterGTL Mazda 12A Street Port minimum weight reduced to 1950 lbs from 2000 lbs.
STL Request to add wheel part numbers #28342wordingwordingSTL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL.
AS Rear Trailing Arms #28007suspension & brakessuspension & brakesAS rear trailing arms may be replaced with tubular arms maintaining stock length and axle location purpose only.
AS Weight reduction for cars running iron heads #28010weightfasterAS Ford and GM full-prep cars get 200 lb weight reduction, up from 150 lb.
AS 05-10 Mustang with HR cam classification #28226cars addedcars added05-10 Ford Mustang Coupe GT 4.6L OHC classified AS with 3200 lbs minimum weight, HR cam restricted prep.
AS 10-15 Camaro Full Prep classification #28227cars addedcars addedAS 10-15 Chevrolet Camaro Full Prep classified with 3400 lbs base weight, over 313 CID engine 3700 lbs maximum.
GTL Windshield Clips #27323wordingwordingGT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications.
GTL Request Factory Five Daytona coupe classification #26308cars addedcars addedFactory Five Type 65 Coupe R with Ford 302/351 or 5.0/5.2L NA added to GTX-MISC at 2600 lbs.
GTL Request to Classify the MK1 two door Jetta #27648cars addedcars addedGTL adds Jetta Mk1 two door classification effective 2020-01-01.
GTL 88-91 Honda CRX Spec Line Correction #27233wordingwordingGTL Honda CRX 84-87 and 88-91 remove IRS option with 2.5% weight penalty.
AS Request to add SMG to 9.1.6.B.1 AS Intent #27140cars addedcars addedAS Spec Mustang (SMG) added as Restricted Prep class.
STL Request to Classify Spec MX-5 Challenge in STL #27399cars addedcars addedMazda Spec MX-5 Challenge classified in STL with 2000cc displacement and 2500 lbs minimum weight.
GTL Fun Cup Beetle #27334wordingwordingGTL Fun Cup Beetle engine weight specified at 1850 lbs with sealed SOHC 1780cc specification.
AS Request Ride Height Clarification #26598wordingwordingAS class minimum ride height clarified to 5 inches measured at rocker panel, excluding seams and cladding.
GTL GTL #26960wordingwordingGTL Fun Cup Beetle removes reference to VW engine table; Fun Cup engine spec remains 1.8L at 2040 lbs.
GTL Request CRZ wheelbase change #26896wordingunclearGTL Honda CRZ 10-14, CRZ 15-16, and Insight 00-06 gain alternate wheelbase option of 90.6 in.
STL Request clarification for manifold and throttle in STU #27004inductionfasterSTU alternate intake manifolds now allowed case-by-case instead of prohibited.
AS Request to Revert to 2017 Weights #25885weightfasterAS Ford Mustang (79-93) 313 CID and under loses 100 lbs to 3150; over 313 CID loses 100 lbs to 3450.
STL Request Restrictor Plate correction #26779inductionfasterSTL Acura/Honda B18 except C engine restrictor increases from 53mm to 54mm flat plate.
GTL Request to Classify VW Fun Cup Beetle #25986cars addedcars addedGTL adds VW Fun Cup Beetle, all model years, 2-door RWD, 94.5-inch wheelbase.
GTL Request GTX Fuel injection for previous GT-1 tube frame cars #26141inductionfasterGTX tube frame cars gain fuel injection with 90mm maximum throttle body size.
GTL Request to Classify Ligier JS2 R #26535cars addedcars addedLigier JS2 R classified in GTX, no performance parameters specified in filing.
GTL Request for GTL Mazda 13B SIR Increase with Penalty #26572engineslowerGTL Mazda 13B may use 25mm SIR with 175 lbs weight penalty added.
STL Request Ride Height Clarification #26597wordingwordingSTL and STU ride height measurement clarified: without driver, at rocker panel lowest point, excluding pinch weld.
GTL Request Ride Height Clarification #26600wordingwordingGT1 and GT2/GT3/LITE ride height requirements removed from GCR sections 9.1.2.D.5.a.1 and 9.1.2.F.7.b.
GTL Request Mazda 12a Rotary SIR Increase #26081inductionfasterGTL Mazda 12A may use 28mm SIR plus 175 lbs.
GTL Request to Classify Mustang 2 Body in GTL #26222cars addedcars addedGTL Mustang 94-04 newly classified in GTL.
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 #25821wordingwordingSTL Mazda MX-5 Cup brake pad compound changed to open.
STL Request to clarify B18C1 GSR Honda B motor table #26209cars addedcars addedSTL 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.
AS SMG Mustang eligibility in American sedan #26224cars addedcars addedAS Spec Mustang (SMG) newly classified with 107.1 wheelbase, 3.73 gears, 355mm front brakes, 300mm rear.
GTL Request for GTL Mini Adjustments #25754weightfasterGTL Mini 1275-1399 Iron and Aluminum Crossflow gain 75 lbs weight reduction to 125 lbs with OE common sump gearbox.
GTL BMC thru Rover Group remove long inactive mini #25771removedremovedGTL BMC thru Rover Group removes long inactive Mini engines: 948, 970, 1071, 1098.
GTL GTX Homologation table update #26034cars addedcars addedGTX FIA GT3: Audi R8 40mm restrictor 2900 lbs, BMW Z4 70mm 2800 lbs, Ferrari 488 35mm restrictor 3025 lbs classified.
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.
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 AS" is the class's best as a share of AS'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 AS'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.