BoP Lab / Michelin Raceway Road Atlanta

AS vs FE2 vs F6 vs FX pace at Michelin Raceway Road Atlanta

Quickest here: AS 1:34.231 Tom Ellis, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta qualifying · FE2 1:22.855 Paul Schneider, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta race · F6 1:30.014 Clint McMahan, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta qualifying · FX 1:25.399 Trent Walko, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta race

Lap times% of AS

ASFE2F6FXsolid race · dashed qualifying · slower is lower

ASFE2F6FXsolid 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			FE2					F6					FX
	Event	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%)	1:24.639Paul Schneider · fastest of 7 · top 5 within 2.4s+1.503s (+1.81%)	1:24.978Paul Schneider · fastest of 7 · top 5 within 2.9s+1.478s (+1.77%)	138.5Paul Schneider+4.9 mph (+3.6%)	-9.664squal -63.765s	89.8%qual 57.0%	1:30.039Calvin Stewart · fastest of 4 · top 4 within 13.3s+0.025s (+0.03%)	1:33.719H Cory Mcleod · fastest of 3 · top 3 within 14.2s+3.452s (+3.82%)	137.8Calvin Stewart+5.7 mph (+4.3%)	-0.923squal -58.365s	99.0%qual 60.7%
13 rule changes (AS: 11, FE2: 2)2 induction · 2 weight · 1 cars added · 8 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. · 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. · 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. · FE and FE2 Enterprises must use bubble tail P/N WM138014; FE2 allows only this configuration. · 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 · 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. · 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. · FE2 allows driver safety and comfort modifications for disabled drivers with SCCA approval, not transferable to other drivers.showhide 2026-03-01 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. 2026-02-01 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. 2026-01-01 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. 2025-12-01 AS 1994 Mustang Spec Line Request #39104wordingunclearAS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft. 2025-11-01 AS Cadillac CTS-V BOP Weight Change #38640weight -50 lbsfasterAS Cadillac CTS-V 04-07 Restricted Prep weight reduced 50 lbs to 3400. 2025-10-01 FE2 FE & FE2 Bubble Tail #38978wordingwordingFE and FE2 Enterprises must use bubble tail P/N WM138014; FE2 allows only this configuration. 2025-07-01 AS RE: Previous Letter 37695 Update #38245weight -75 lbsfasterAS Ford Mustang GT 5.0 2018- weight reduced from 3600 to 3525 lbs. 2025-06-01 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 2025-05-01 AS Errors and Omission #38055inductionslowerAS Ford Mustang GT 5.0L (15-17) flat plate restrictor reduced from 67mm to 64mm. 2025-05-01 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. 2025-04-01 AS Flotek Head Plunge Cut Inconsistencies #37502wordingunclearAS Flotek Head plunge cut dimensions figure updated in GCR Section 9.1.6. 2025-04-01 AS Notes clean up #37693wordingwordingAS class notes cleanup: multiple Camaro, Firebird, CTS-V, Challenger, Mustang specs and fuel cell/ECM/head restrictions removed. 2025-04-01 FE2 Driver Safety & Comfort #37965wordingwordingFE2 allows driver safety and comfort modifications for disabled drivers with SCCA approval, not transferable to other drivers.
	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%)	1:23.136Franklin Futrelle · fastest of 8 · top 5 within 2.1s-0.076s (-0.09%)	1:23.500Franklin Futrelle · fastest of 8 · top 5 within 1.9s-0.914s (-1.08%)	133.6Eric Wisniewski+1.7 mph (+1.3%)	-11.851squal -12.331s	87.6%qual 87.1%
15 rule changes (AS: 12, FX: 3)4 cars added · 2 engine · 2 weight · 1 induction · 1 tyres & wheels · 4 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. · FX Ligier JS F422 loses 15 lbs, to 1360 minimum weight. · AS Ford Mustang GT models gain alternate transmission ratio options for 2024-09-01. · FX Ligier JS F4 1st Gen minimum weight drops to 1405 lbs; 2nd Gen rises to 1375 lbs. · 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. · 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. · FX adds 2nd Gen Ligier JS F422 classification effective 2024-04-01.showhide 2025-03-01 AS Race memo #37902wordingunclearAS Spec Lines removes ECM flexibility restriction from five Cadillac and Chevrolet/Pontiac V8 models. 2025-01-01 AS Increase Coyote Engine Restrictor to 80mm #36177inductionfasterAS Ford Mustang Coyote engines increase restrictor to 80mm from 64mm or 67mm. 2025-01-01 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. 2025-01-01 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. 2025-01-01 AS ECU specs for LS engine #37208enginefasterAS LS-engine cars gain ECU freedom; Camaro/Firebird 93-02 LS1 removes fuel cell location restriction. 2024-12-01 FX Request to Change to Weight for Ligier JS F422 #37124weight -15 lbsfasterFX Ligier JS F422 loses 15 lbs, to 1360 minimum weight. 2024-09-01 AS Mustang transmission ratios #36662wordingunclearAS Ford Mustang GT models gain alternate transmission ratio options for 2024-09-01. 2024-07-01 FX Adjust minimum weights to align with pro F4 rules #36221weight -15 lbsfasterFX Ligier JS F4 1st Gen minimum weight drops to 1405 lbs; 2nd Gen rises to 1375 lbs. 2024-06-01 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. 2024-05-01 AS 6th gen Camaro limited prep #35733cars addedcars addedAS Chevrolet Camaro 1LE (2016-) classified with 3600 lbs minimum weight, 60mm restrictor, 275 tires. 2024-05-01 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. 2024-05-01 AS Full Prep Head #35891otherotherAS Chevrolet Camaro, Firebird, and Ford Mustang models permitted to use Flo Tek cylinder heads. 2024-04-01 AS Restricted Prep Aftermarket Parts Request #35682wordingwordingAS Camaro/Firebird and GTO LS1 connecting rods approved: Callies CSC6100DS6A2AH, Scat 2-1CR6100-944, GM 12649190. 2024-04-01 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. 2024-04-01 FX Add Classification for 2nd Gen Ligier JS F422 #35844cars addedcars addedFX adds 2nd Gen Ligier JS F422 classification effective 2024-04-01.
	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%)	1:23.212Franklin Futrelle · fastest of 14 · top 5 within 2.3s+0.084s (+0.10%)	1:24.414Charles Russell Turner · fastest of 13 · top 5 within 1.5s-0.040s (-0.05%)	131.9Jason Conzo-9.2 mph (-6.5%)	-35.851squal -21.089s	70.2%qual 79.8%	1:30.014Clint McMahan · fastest of 8 · top 5 within 4.6s-5.777s (-6.03%)	1:30.267Clint McMahan · fastest of 8 · top 5 within 4.8s-4.980s (-5.23%)	132.1Calvin Stewart-3.7 mph (-2.7%)	-29.998squal -14.287s	75.1%qual 86.3%	1:34.337Brad Yake · only car+5.991s (+6.78%)	1:36.351Brad Yake · only car+10.952s (+12.82%)	117.3Brad Yake-19.8 mph (-14.4%)	-23.914squal -9.964s	80.1%qual 90.4%
11 rule changes (AS: 8, FX: 3)4 cars added · 1 tyres & wheels · 6 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. · FX Formula 4 now complies with Table 1 notes only; removed reference to FIA 2015 technical regulations and FIA/SCCA safety requirements. · Unable to summarize: FX Formula Mazda spec changes reference attached document not provided. · 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. · USF2000 Van Diemen with Mazda MZR LF-DE 2.0L added as spec line car in FC; removed from FX.showhide 2024-03-01 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. 2024-03-01 AS Fuel Cell 12 #34194wordingwordingAS class: multiple cars gain fuel cell placement note allowing 24 inches from standard tank, unrestricted filler location. 2024-03-01 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. 2024-03-01 AS spec lines #35713cars addedcars addedAS adds Ford Mustang GT 05-14 Restricted prep Engine with 62mm FPR, 3400 lbs minimum, 18-inch wheels. 2024-03-01 FX Clarify Formula 4 Rules in FX #35700wordingunclearFX Formula 4 now complies with Table 1 notes only; removed reference to FIA 2015 technical regulations and FIA/SCCA safety requirements. 2023-11-01 FX FM Rules Update #34841wordingunclearUnable to summarize: FX Formula Mazda spec changes reference attached document not provided. 2023-08-01 AS Crate Motor Part Numbers #32944wordingwordingAS crate motor part number specified: GM Performance CT400 P/N 19370604 engine assembly for GM vehicles. 2023-08-01 AS Request wheel size change #33007tyres & wheelsfasterAS Spec Lines Ford Mustang GT 5.0L (15-17) max wheel size increases to 19.0 inches. 2023-08-01 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. 2023-08-01 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. 2023-06-01 FX USF2000 Van Diemen with Mazda MZR LF-DE 2.0L in FC #34329cars addedcars addedUSF2000 Van Diemen with Mazda MZR LF-DE 2.0L added as spec line car in FC; removed from FX.
	Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST23MAR102023-03-10				1:23.128Franklin Futrelle · fastest of 15 · top 5 within 2.5s+0.032s (+0.04%)	1:24.454Charles Russell Turner · fastest of 15 · top 5 within 1.2s+1.599s (+1.93%)	141.1Eric Cruz-3.0 mph (-2.1%)			1:35.791George Bugg · fastest of 5 · top 5 within 8.8s	1:35.247H Cory McLeod · fastest of 5 · top 5 within 9.3s	135.8Jack Walbran
10 rule changes (AS: 3, FX: 7)2 engine · 2 weight · 1 cars added · 1 induction · 1 tyres & wheels · 3 wording · FX: Wording clarified to remove references to FB and FM in GCR section 1.4.2.D. · Formula Renault 2.0 (10-17) reclassified from FX to FA; weight reduced to 1280 lbs, restrictor removed. · 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. · Pro Formula F2000 tube frame reduced to 4 forward gears, sequential carries 25 lb. weight penalty. · FX Formula Mazda minimum weight exception set to 1270 lb. · FX Formula Mazda engine spec changed to six-port 13B only; weight now per notes instead of 1350/1400. · AS Cadillac CTS-V 6.0L V8 removes 50 lbs weight penalty for 295 tire size. · Formula Renault 2.0 (10-17) now requires 45mm Flat Plate Intake Restrictor; fairings prohibited before or after. · USF2000 Tube Frame may now use Performance Electronics PE3-8400 ECU as alternative to Pectel T2.showhide 2023-02-01 FX E&O - Remove references to FB and FM in GCR section 1.4.2.D #33725wordingwordingFX: Wording clarified to remove references to FB and FM in GCR section 1.4.2.D. 2022-12-01 FX Reclassify 2010-2017 Formula Renault 2.0 as a spec line car in FA #33395cars addedfasterFormula Renault 2.0 (10-17) reclassified from FX to FA; weight reduced to 1280 lbs, restrictor removed. 2022-09-01 AS Request to add Hoosier W2 #33031tyres & wheelstyres & wheelsAS allows Hoosier W2 tyre option in addition to R7, R6, WET/H20. 2022-09-01 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. 2022-08-01 FX Pro Formula F2000/USF2000 Transmission E&O #32823engineslowerPro Formula F2000 tube frame reduced to 4 forward gears, sequential carries 25 lb. weight penalty. 2022-08-01 FX Formula Mazda Minimum Weight #33010weightslowerFX Formula Mazda minimum weight exception set to 1270 lb. 2022-08-01 FX Formula Mazda Spec Line E&O Corrections #33011engineunclearFX Formula Mazda engine spec changed to six-port 13B only; weight now per notes instead of 1350/1400. 2022-07-01 AS Request CTS-V Spec Line Error Correction #30242weightfasterAS Cadillac CTS-V 6.0L V8 removes 50 lbs weight penalty for 295 tire size. 2022-07-01 FX Formula Renault 2.0 (10-17) Intake Restrictor #32745inductionslowerFormula Renault 2.0 (10-17) now requires 45mm Flat Plate Intake Restrictor; fairings prohibited before or after. 2022-07-01 FX Allow Performance Electronics PE3-8400 for USF2000 MZR #32767wordingwordingUSF2000 Tube Frame may now use Performance Electronics PE3-8400 ECU as alternative to Pectel T2.
	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+2.115s (+2.24%)	1:35.993Gregory Eaton · fastest of 2+1.259s (+1.33%)	143.6Gregory Eaton-19.3 mph (-11.9%)	1:23.096Paul Schneider · fastest of 13 · top 5 within 2.8s-1.268s (-1.50%)	1:22.855Paul Schneider · fastest of 13 · top 5 within 2.5s-1.101s (-1.31%)	144.1Bailey Monette+5.2 mph (+3.8%)	-13.138squal -13.250s	86.3%qual 86.2%						1:28.346Trent Walko · fastest of 4 · top 4 within 6.6s+0.215s (+0.24%)	1:25.399Trent Walko · fastest of 4 · top 4 within 5.7s-2.391s (-2.72%)	137.1Trent Walko+2.7 mph (+2.0%)	-10.594squal -8.000s	89.0%qual 91.7%
18 rule changes (AS: 11, FX: 7)4 tyres & wheels · 3 weight · 2 engine · 1 cars added · 1 suspension & brakes · 6 wording · 1 other · Formula Mazda tire marking no longer required; compliance now referenced to updated online specifications document. · FX Formula 4 tire choice becomes unrestricted; must comply with FIA F4 2015 Technical Regulations and subsequent safety requirements. · FX USF2000 Tube Frame front tyre changes from radial to unspecified type, rear tyre options added. · FX Formula Renault 2.0 (00-17) tire choice unrestricted; original components required except repairs. · 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. · 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. · FX USF2000 Tube Frame allows Hoosier radials 20.5x7.0x13 front and 22.5x8.0x13 rear, FC-compliant shocks, Wilwood brakes, Bosch spark plugs. · 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. · FX USF2000 Tube Frame now allows any Hoosier radial tire 20.5x7.0x13 front, 22.5x8.0x13 rear. · FX adds 2000-2009 Formula Renault 2.0 / Fran-Am 2000 classified at 1250 lbs with sealed 2.0L Renault F4R 832 engine.showhide 2022-02-01 FX FM Rule Set Clarification #31881wordingwordingFormula Mazda tire marking no longer required; compliance now referenced to updated online specifications document. 2022-02-01 FX E&O F4 Tires #31940tyres & wheelsfasterFX Formula 4 tire choice becomes unrestricted; must comply with FIA F4 2015 Technical Regulations and subsequent safety requirements. 2022-02-01 FX E&O USF2000 Tube Frame #31951tyres & wheelsunclearFX USF2000 Tube Frame front tyre changes from radial to unspecified type, rear tyre options added. 2022-02-01 FX URGENT - FX- Formula Renault Tire #32058tyres & wheelsfasterFX Formula Renault 2.0 (00-17) tire choice unrestricted; original components required except repairs. 2022-01-01 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. 2022-01-01 AS specification line consolidation and correction #31846wordingwordingAS Mercury Capri (79-86) removed as individual spec line, merged into Ford Mustang (79-93) spec line. 2022-01-01 AS correction of SMG specification line #31847wordingunclearAS Spec Mustang SMG loses 3.73 gear ratio and 355/300 mm brake specification. 2022-01-01 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. 2021-10-01 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. 2021-10-01 AS Request Pontiac GTO tire size change #30881weightslowerAS Pontiac GTO 04-06 LS1 to 3300 lbs, LS2 to 3350 lbs on 295 tire. 2021-08-01 FX Rules Adjustment #30950otherotherFX USF2000 Tube Frame allows Hoosier radials 20.5x7.0x13 front and 22.5x8.0x13 rear, FC-compliant shocks, Wilwood brakes, Bosch spark plugs. 2021-06-01 AS Request CTS-V Spec Line Error Correction #30242weightfasterAS Cadillac CTS-V 6.0L V8 removes 50 lbs tire size penalty, making it lighter. 2021-06-01 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. 2021-06-01 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. 2021-06-01 AS Correction to specifications inadvertently deleted #30691wordingwordingAS Camaro/Firebird and Mustang GT gear ratio specifications restored with alternate sets permitted. 2021-06-01 AS weight adjustments #30700weight +50 lbsslowerAS Chevrolet Camaro & Firebird, Ford Mustang variants, Mercury Capri minimum weights increase 50 lbs across all model years. 2021-06-01 FX FX/FRP Tire Rule #30723tyres & wheelstyres & wheelsFX USF2000 Tube Frame now allows any Hoosier radial tire 20.5x7.0x13 front, 22.5x8.0x13 rear. 2021-05-01 FX Classify the 2000-2009 Formula Renault 2.0 / Fran-Am 2000 #30460cars addedcars addedFX adds 2000-2009 Formula Renault 2.0 / Fran-Am 2000 classified at 1250 lbs with sealed 2.0L Renault F4R 832 engine.
	Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST21MAR192021-03-19	1:34.231Tom Ellis · fastest of 7 · top 5 within 7.4s	1:34.734Tom Ellis · fastest of 7 · top 5 within 5.6s	163.0Tom Ellis	1:24.364Bailey Monette · fastest of 18 · top 5 within 1.3s	1:23.956Bailey Monette · fastest of 18 · top 5 within 0.8s	138.9T Vanacore	-10.778squal -9.867s	88.6%qual 89.5%						1:28.131Austin Hill · fastest of 6 · top 5 within 3.8s	1:27.790Austin Hill · fastest of 6 · top 5 within 4.1s	134.4Austin Hill	-6.944squal -6.100s	92.7%qual 93.5%
39 earlier rule changes on record, in force before Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta (from 2019)11 cars added · 7 weight · 4 engine · 3 suspension & brakes · 2 tyres & wheels · 11 wording · 1 other · 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. · 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. · Formula Renault 2.0 (2010–2017) newly classified in FX, must comply with Table 1 notes. · 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. · FX FormulaSPEED FS2.0 specification requirements updated; World Speed Inc. deadline removed, compliance now per SCCA website. · 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. · Formula Ireland / Formula FX added to FX classification under Table 1 with compliance notes. · 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. · 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. · Formula Ireland/Formula FX car addition to FX Table 1 pending specification submission; not recommended. · AS Chevrolet/Pontiac Camaro & Firebird (82-92) loses 50 lbs, to 3500. · Ex-Pro Formula Super Vee classified in FX with 1190 lbs minimum weight, 1600cc or 1835cc VW engine, 6in front and 8in rear wheels. · FormulaSPEED reclassified from FA to FX with 2.0L Mazda MZR engine, 1350 lbs minimum weight, sealed ECU and dampers. · FX Formula Mazda no longer requires tire marking; must comply with December 2019 GCR rules. · 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. · Pro Formula F 2000 Tube Frame engine now must follow current FC rules with restricted ECU map, cams, and air restrictor required. · FE and FE2 minimum weight increased to 1270 lbs including driver; spring options and tire warmer ban added. · AS Spec Mustang (SMG) added as Restricted Prep class. · AS class minimum ride height clarified to 5 inches measured at rocker panel, excluding seams and cladding. · AS Ford Mustang (79-93) 313 CID and under loses 100 lbs to 3150; over 313 CID loses 100 lbs to 3450. · AS Spec Mustang (SMG) newly classified with 107.1 wheelbase, 3.73 gears, 355mm front brakes, 300mm rear.showhide 2021-03-01 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. 2021-03-01 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. 2021-03-01 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. 2021-01-01 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. 2021-01-01 AS Request Trunk lid / Rear Hatch clarification #29591wordingwordingAS underhood bracing on stock hoods, trunks, and rear decks may be modified or removed. 2021-01-01 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. 2021-01-01 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. 2021-01-01 FX Request for Car Classification to Compete in Formula X #29933cars addedcars addedFormula Renault 2.0 (2010–2017) newly classified in FX, must comply with Table 1 notes. 2020-12-01 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. 2020-12-01 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. 2020-12-01 FX Update specifications for FormulaSPEED cars #29674wordingwordingFX FormulaSPEED FS2.0 specification requirements updated; World Speed Inc. deadline removed, compliance now per SCCA website. 2020-09-01 FE2 FE/FE2 Oil Cooler #29293wordingwordingFE2 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. 2020-09-01 FX Follow up to to Letter#28991 Request for FX classification #29281cars addedcars addedFormula Ireland / Formula FX added to FX classification under Table 1 with compliance notes. 2020-08-01 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°. 2020-08-01 AS Dodge Challenger AS Spec Line Clarification #2 #28699wordingwordingAS Dodge Challenger 08-14 rear spoiler part number changes from 1GL20RXF to 1GL20TZZAB. 2020-07-01 AS Support for R-Type Specification Tires #27450tyres & wheelsunclearAS class pursues specified list of eligible tires; details of tire changes not provided in letter. 2020-07-01 AS Spec Tire Request #27519tyres & wheelsunclearAS class pursuing specified list of eligible tires; details pending further communication. 2020-07-01 AS Restrictor Plate Change for RP 2011+ Mustang with Coyote Engine #27675wordingunclearNo restrictor plate change implemented; 2021 AS Mustang Coyote under evaluation. 2020-07-01 AS 2005-2009 Restricted Prep 4.6 3V #27908engineunclearAS 2005-2009 Restricted Prep 4.6 3V now permits conversion to 2 valve configuration. 2020-07-01 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. 2020-07-01 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. 2020-07-01 AS Cylinder Heads #28696wordingunclearAS class cylinder head replacement options under review; implementation planned for 2021 season. 2020-07-01 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. 2020-07-01 AS Request increase rotor diameter #28797suspension & brakessuspension & brakesAS rotor diameter increase approved; see Fastrack letter #28748 for details. 2020-07-01 FX Request to be added to FX group #28991cars addedcars addedFormula Ireland/Formula FX car addition to FX Table 1 pending specification submission; not recommended. 2020-05-01 AS weight adjustments for 2020 season #28785weight -50 lbsfasterAS Chevrolet/Pontiac Camaro & Firebird (82-92) loses 50 lbs, to 3500. 2020-04-01 FX Request to classify FSV in FX #28057cars addedcars addedEx-Pro Formula Super Vee classified in FX with 1190 lbs minimum weight, 1600cc or 1835cc VW engine, 6in front and 8in rear wheels. 2020-04-01 FX Classify FormulaSPEED in FX #28715cars addedcars addedFormulaSPEED reclassified from FA to FX with 2.0L Mazda MZR engine, 1350 lbs minimum weight, sealed ECU and dampers. 2020-03-01 FX Request to remove tire marking language from FM #28415wordingwordingFX Formula Mazda no longer requires tire marking; must comply with December 2019 GCR rules. 2020-02-01 AS Rear Trailing Arms #28007suspension & brakessuspension & brakesAS rear trailing arms may be replaced with tubular arms maintaining stock length and axle location purpose only. 2020-02-01 AS Weight reduction for cars running iron heads #28010weightfasterAS Ford and GM full-prep cars get 200 lb weight reduction, up from 150 lb. 2020-02-01 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. 2020-02-01 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. 2020-02-01 FX Change to FX Table 1 #28322engineslowerPro Formula F 2000 Tube Frame engine now must follow current FC rules with restricted ECU map, cams, and air restrictor required. 2019-12-01 FE2 FE / FE2 Update Rules #27624weightslowerFE and FE2 minimum weight increased to 1270 lbs including driver; spring options and tire warmer ban added. 2019-10-01 AS Request to add SMG to 9.1.6.B.1 AS Intent #27140cars addedcars addedAS Spec Mustang (SMG) added as Restricted Prep class. 2019-08-01 AS Request Ride Height Clarification #26598wordingwordingAS class minimum ride height clarified to 5 inches measured at rocker panel, excluding seams and cladding. 2019-05-31 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. 2019-02-01 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.

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.