FX vs SM vs FP vs AS pace at Michelin Raceway Road Atlanta
Quickest here:FX 1:25.399 Trent Walko, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta race · SM 1:41.864 Travis Wiley, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta race · FP 1:37.623 Ken Kannard, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta race · AS 1:34.642 Michael Kamalian, Atlanta Region SCCA Hoosier Super Tour @ Michelin Raceway Road Atlanta race
FXSMFPASsolid race · dashed qualifying · slower is lower
FXSMFPASsolid race · dashed qualifying · each class's best lap as a share of FX's at the same event (the reference class, changeable above); 100% is level, higher is quicker
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FP
AS
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Race best
Trap
Qual best
Race best
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Atlanta Region SCCA Hoosier Super Tour @ Michelin Raceway Road Atlanta ST26MAR062026-03-06
1:42.324Skyler Cottrell · fastest of 52 · top 5 within 0.4s-0.524s (-0.51%)
1:42.611Charles Mactutus · fastest of 51 · top 5 within 0.2s-0.014s (-0.01%)
112.2James Newell+5.2 mph (+4.9%)
1:39.075Ken Kannard · fastest of 4 · top 4 within 2.6s+0.849s (+0.86%)
1:39.386Cliff Ira · fastest of 4 · top 4 within 2.8s+0.948s (+0.96%)
124.2Cliff Ira+5.8 mph (+4.9%)
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%)
43 rule changes (SM: 3, FP: 29, AS: 11)11 weight · 6 induction · 5 cars added · 4 engine · 17 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. · FP Fiat X-1/9 1300 and 1500 intake valves increased to 36.3mm, exhaust valves corrected to 31.2mm and 33.3mm. · FP Fiat X-1/9 & Bertone dual carburetors increase from 28mm to 30mm choke. · AS Chevy LS adds Edelbrock Performer RPM 71187 intake manifold with MSD 6014 ignition and 4776 Holly carburetor as spec line option. · FP class adds Toyota 5E DOHC 1497cc engine, 1900 lbs minimum weight, 23mm SIR induction. · FP Toyota 4E DOHC 1331cc engine added to Appendix N with 1900 lbs minimum weight. · FP Fiat X1/9 gains dual carburetor options with 28mm side-draft alternates and revised valve/transmission specs. · 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. · EP Triumph TR2-TR4A allows 5-speed gearbox without overdrive; removes Weber carb and weight specification. · EP BMW Z3 2.5L restrictor reduced 52mm to 50mm, weight increased to 2550 lbs base; five other BMW models get smaller restrictors. · FP Lancia Scorpion minimum weight drops 80 lbs, to 1950. · FP Volkswagen Rabbit Convertible no longer required to remove factory roll bar. · FP Acura Integras and Honda Civics gain 50–79 lbs; Mazda Miata and Mercury Capri compression ratio to 11.0:1, valve lift to .425". · FP Honda B/D-series engines gain 105–120 lbs minimum weight across seven variants. · AS Cadillac CTS-V 04-07 Restricted Prep weight reduced 50 lbs to 3400. · EP Nissan 280Z minimum weight reduced from 2560 to 2400 lbs. · EP Mazda MX-5 1.8L 90-97 weight reduced to 2125 lbs from 2150 lbs. · HP Austin-Healey Sprite/Midget 1098cc minimum weight drops 80 lbs to 1550. · HP Volvo 142/142E gains compression ratio limit 12.0:1 and valve lift limit .425". · HP Mini Cooper 07-15 valve lift reduced to .390", from .450". · FP Scirocco 83-88 established as spec line with 1733–1803 lbs, 1715–1780 cc SOHC, 40/33 mm valves, Solex carbs or fuel injection. · FP and HP Volkswagen Rabbit descriptions updated: Convertible changed to Cabriolet in FP; Cabriolet added to three HP engine variants. · EP, FP, HP: rear drum brake to disc conversion clarified; rotors solid, diameter limited to largest front rotor permitted. · EP Ford Mustang (94-98) fuel injected throttle body inside diameter specified at 60. · FP Volkswagen Scirocco: remove two engine variants (1715cc and 1780cc), lighten one variant to 1663 lbs, allow 15×7 wheels instead of 13×7. · HP Plymouth Arrow transmission max speeds clarified to 4 or 5. · EP, FP, HP wheel diameter added to Appendix G as absolute maximum specification. · EP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only. · AS Ford Mustang GT 5.0 2018- weight reduced from 3600 to 3525 lbs. · EP BMW Z4 03-05 restricted to 52mm flat plate intake restrictor. · EP Fiat 124 Spider 1600 & 2000 weight drops 50 lbs to 2000; carburetors gain 2mm chokes to 36mm. · AS Ford Mustang GT 05-14 Restricted Prep Engine gains alternative gear ratios: 3.66, 2.43, 1.69, 1.32, 1.00, .65 · HP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines. · 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. · SM cars limited to one set of Hoosier SM 7.5 P205/50/ZR17 per Super Tour event weekend for dry sessions. · 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. · Chevrolet Spark 16-22 classified HP Pre at 1850 lbs minimum weight, fuel injected, 1399 cc. · HP Ford Festiva 88-93 minimum weight drops to 1600 lbs, variants to 1640 and 1680 lbs; compression ratio raised to 11.0:1.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.
FP Correct Valve Sizes on FP Fiat x19 1300 and 1500 #39850enginefasterFP Fiat X-1/9 1300 and 1500 intake valves increased to 36.3mm, exhaust valves corrected to 31.2mm and 33.3mm.
FP Dual Carburetor Adjustments #39851inductionfasterFP Fiat X-1/9 & Bertone dual carburetors increase from 28mm to 30mm choke.
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.
FP Request Toyota 5E Series Engines #38208cars addedcars addedFP class adds Toyota 5E DOHC 1497cc engine, 1900 lbs minimum weight, 23mm SIR induction.
FP Request for Toyota 4E Series Engines #38209cars addedcars addedFP Toyota 4E DOHC 1331cc engine added to Appendix N with 1900 lbs minimum weight.
FP Dual Carbs for the Fiat X1/9 #39593inductionunclearFP Fiat X1/9 gains dual carburetor options with 28mm side-draft alternates and revised valve/transmission specs.
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.
AS 1994 Mustang Spec Line Request #39104wordingunclearAS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft.
FP TR2 Notes E&O #39180wordingunclearEP Triumph TR2-TR4A allows 5-speed gearbox without overdrive; removes Weber carb and weight specification.
FP Balance of Power #39187induction +50 lbsslowerEP BMW Z3 2.5L restrictor reduced 52mm to 50mm, weight increased to 2550 lbs base; five other BMW models get smaller restrictors.
FP Factory Roll Bar Removal on VW Convertible #39268wordingwordingFP Volkswagen Rabbit Convertible no longer required to remove factory roll bar.
FP FP Parity Request #39325weight +50 lbsslowerFP Acura Integras and Honda Civics gain 50–79 lbs; Mazda Miata and Mercury Capri compression ratio to 11.0:1, valve lift to .425".
FP Adjust former-GTL Honda's with B/D-Series Engines #39374weightslowerFP Honda B/D-series engines gain 105–120 lbs minimum weight across seven variants.
AS Cadillac CTS-V BOP Weight Change #38640weight -50 lbsfasterAS Cadillac CTS-V 04-07 Restricted Prep weight reduced 50 lbs to 3400.
FP Please Lower Weight of 280Z #38871weight -160 lbsfasterEP Nissan 280Z minimum weight reduced from 2560 to 2400 lbs.
FP Miata Weight Adjustment Follow Up #38949weight -25 lbsfasterEP Mazda MX-5 1.8L 90-97 weight reduced to 2125 lbs from 2150 lbs.
FP HP Volvo 142 spec omission #38994engineslowerHP Volvo 142/142E gains compression ratio limit 12.0:1 and valve lift limit .425".
FP HP Mini DOHC 1.6 #38996engineslowerHP Mini Cooper 07-15 valve lift reduced to .390", from .450".
FP 83-88 FP Scirocco Spec Line Creation #38997cars addedcars addedFP Scirocco 83-88 established as spec line with 1733–1803 lbs, 1715–1780 cc SOHC, 40/33 mm valves, Solex carbs or fuel injection.
FP Add to Rabbit description #39019wordingwordingFP and HP Volkswagen Rabbit descriptions updated: Convertible changed to Cabriolet in FP; Cabriolet added to three HP engine variants.
FP Clean-up 9.1.5.E.7e #39025wordingwordingEP, FP, HP: rear drum brake to disc conversion clarified; rotors solid, diameter limited to largest front rotor permitted.
FP Add TB size to Ford Mustang (94-98) Spec Line #39130wordingwordingEP Ford Mustang (94-98) fuel injected throttle body inside diameter specified at 60.
FP Correct Existing VW Scirocco Spec Line #39140enginefasterFP Volkswagen Scirocco: remove two engine variants (1715cc and 1780cc), lighten one variant to 1663 lbs, allow 15×7 wheels instead of 13×7.
FP HP Plymouth Arrow spec omission #38995wordingwordingHP Plymouth Arrow transmission max speeds clarified to 4 or 5.
FP Add Wheel Diameter to Appendix G #39008wordingwordingEP, FP, HP wheel diameter added to Appendix G as absolute maximum specification.
FP Add TB ID tolerance to general Prod rules #39009wordingwordingEP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only.
AS RE: Previous Letter 37695 Update #38245weight -75 lbsfasterAS Ford Mustang GT 5.0 2018- weight reduced from 3600 to 3525 lbs.
FP BMW Z4 update #38490inductionslowerEP BMW Z4 03-05 restricted to 52mm flat plate intake restrictor.
FP EP Fiat 124 Spider Competition Adjustment Request #38498weight -50 lbsfasterEP Fiat 124 Spider 1600 & 2000 weight drops 50 lbs to 2000; carburetors gain 2mm chokes to 36mm.
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
FP Base Weight Adjustment for H-Production X1/9 Spec Lines #38255weight -50 lbsfasterHP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines.
SM SMX Data Submission - Penalties #38248wordingwordingSMX drivers must submit data acquisition files on time or face suspension and $250 fine.
SM 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.
SM Clarify Tire Marking Regs #38005wordingwordingSM cars limited to one set of Hoosier SM 7.5 P205/50/ZR17 per Super Tour event weekend for dry sessions.
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.
FP Request for Classification of Chevrolet Spark #37755cars addedcars addedChevrolet Spark 16-22 classified HP Pre at 1850 lbs minimum weight, fuel injected, 1399 cc.
FP Request to Lower Ford Festiva Minimum Weight to 1600 LBS #37939weight -100 lbsfasterHP Ford Festiva 88-93 minimum weight drops to 1600 lbs, variants to 1640 and 1680 lbs; compression ratio raised to 11.0:1.
Atlanta Region SCCA Hoosier Super Tour @ Michelin Raceway Road Atlanta ST25MAR072025-03-07
1:42.848Sean Noonan · fastest of 35 · top 5 within 0.2s+0.228s (+0.22%)
1:42.625Sean Noonan · fastest of 33 · top 5 within 0.6s-0.370s (-0.36%)
107.0Sean Noonan+1.8 mph (+1.7%)
1:38.226Mason Workman · fastest of 5 · top 5 within 3.6s+0.302s (+0.31%)
1:38.438Ken Kannard · fastest of 5 · top 5 within 3.2s+0.815s (+0.83%)
118.3Ken Kannard-0.7 mph (-0.6%)
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%)
39 rule changes (FX: 3, SM: 5, FP: 19, AS: 12)8 cars added · 6 induction · 5 weight · 4 engine · 1 tyres & wheels · 14 wording · 1 other · AS Spec Lines removes ECM flexibility restriction from five Cadillac and Chevrolet/Pontiac V8 models. · EP BMW Z3 and 3-series models get smaller intake restrictors: Z3 2.5L to 52mm, Z3 2.8L to 55mm, 328i to 58mm, 325i to 56mm. · FP Acura Integra and Honda Civic models get smaller 51mm intake restrictors, down from 55mm; Del Sol VTEC weight increases to 2290–2405 lbs. · EP, FP, HP: interior or exterior mirrors meeting rule 9.3.36 now permitted. · EP Honda S2000 1997cc base loses 75 lbs to 2375; 2157cc base loses 60 lbs to 2450. · EP Mazda MX-5/Miata 99-05 minimum weight drops to 2100 lbs, 2153 lbs with power adder, 2205 lbs with two adders. · FP GTL Volkswagen Jetta Mark IV 4dr FWD 98.2 wheelbase newly classified. · FP Spec Lines option: carburettor chokes permitted as alternative to SIR, same size as listed SIR. · EP BMW Z3 2.5L requires 52mm flat plate intake restrictor; Z3 2.8L 55mm; 328i/is E36 58mm; 328i/ci E46 58mm; 325i/is E46 56mm; 325i/is E36 56mm; 325is M-Technic 56mm. · 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. · EP BMW 325i/is E30 (84-91) weight reduced 50–52 lbs across three spec lines to 2150, 2204, 2258. · FP Spridget and Midget 1275cc and 1500cc spec line corrections to bore, stroke, displacement, and valve sizes. · F Production now allows GT-Lite cars meeting Appendix N specifications to compete, effective 2025-01-01. · FX Ligier JS F422 loses 15 lbs, to 1360 minimum weight. · SMX allows OE instrument cluster relocation for aftermarket dash mounting, with wiring re-routed only; alternate gauges now permitted. · HP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1. · FP Honda CRX/CRX Si 84-87 block material changes from Iron to Alum. · AS Ford Mustang GT models gain alternate transmission ratio options for 2024-09-01. · 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. · HP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in). · 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. · Nissan 300ZX 84-89 classified to EP at 2550 lbs minimum, 2960cc 6-cyl SOHC, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit. · Mazda RX-7 92-97 newly classified EP Prep Level 2 at 2200–2310 lbs with 13B 6-port rotary engine. · EP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains. · 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. · FP Honda CRX 84-87 can replace plastic front header, rocker skirt, door cap panels with stock-appearance replicas in alternate materials. · FP Acura Integra and Honda Civic models now require 55mm Flat Plate Intake Restrictor. · 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
AS Race memo #37902wordingunclearAS Spec Lines removes ECM flexibility restriction from five Cadillac and Chevrolet/Pontiac V8 models.
FP Request Competition Adjustment to BMW Z3 2.5L #37120inductionslowerEP BMW Z3 and 3-series models get smaller intake restrictors: Z3 2.5L to 52mm, Z3 2.8L to 55mm, 328i to 58mm, 325i to 56mm.
FP FP Class Adjustments #37458inductionslowerFP Acura Integra and Honda Civic models get smaller 51mm intake restrictors, down from 55mm; Del Sol VTEC weight increases to 2290–2405 lbs.
FP Interpretation of Production Rules on Mirrors #37235wordingwordingEP, FP, HP: interior or exterior mirrors meeting rule 9.3.36 now permitted.
FP Weight Reduction for Honda S2000 #37466weightfasterEP Honda S2000 1997cc base loses 75 lbs to 2375; 2157cc base loses 60 lbs to 2450.
FP Mazda 1999 Miata 1.8L #37488weight -50 lbsfasterEP Mazda MX-5/Miata 99-05 minimum weight drops to 2100 lbs, 2153 lbs with power adder, 2205 lbs with two adders.
FP Errors & Omissions #37648cars addedcars addedFP GTL Volkswagen Jetta Mark IV 4dr FWD 98.2 wheelbase newly classified.
FP GTL/FP consolidation 2025 Rules #37659inductioninductionFP Spec Lines option: carburettor chokes permitted as alternative to SIR, same size as listed SIR.
FP Effective date for Jan 2025 GCR updates #37654inductionslowerEP BMW Z3 2.5L requires 52mm flat plate intake restrictor; Z3 2.8L 55mm; 328i/is E36 58mm; 328i/ci E46 58mm; 325i/is E46 56mm; 325i/is E36 56mm; 325is M-Technic 56mm.
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.
FP Request to Reduce Weight of BMW 325i/is E30 (84-91) Spec Line #37119weight -50 lbsfasterEP BMW 325i/is E30 (84-91) weight reduced 50–52 lbs across three spec lines to 2150, 2204, 2258.
FP Fix Error in Spridget Spec Line #37437wordingwordingFP Spridget and Midget 1275cc and 1500cc spec line corrections to bore, stroke, displacement, and valve sizes.
FP Create ruleset that allows GTL cars to run in FP #37485cars addedcars addedF Production now allows GT-Lite cars meeting Appendix N specifications to compete, effective 2025-01-01.
FX Request to Change to Weight for Ligier JS F422 #37124weight -15 lbsfasterFX Ligier JS F422 loses 15 lbs, to 1360 minimum weight.
SM 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.
FP 1275 HP Spridget Level 2 Only #36518enginefasterHP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1.
FP Errors/emissions Honda Civic/CRX #36700enginefasterFP Honda CRX/CRX Si 84-87 block material changes from Iron to Alum.
AS Mustang transmission ratios #36662wordingunclearAS Ford Mustang GT models gain alternate transmission ratio options for 2024-09-01.
SM SMX Camera Rule Correction #36496wordingwordingSMX Spec MX-5 camera requirement wording changed; non-functioning recorder now grounds for penalty or disqualification.
SM Committee) AIM ECU Protocol #36556wordingwordingSMX Spec MX-5 must run latest AIM Data Logger Spec MX-5 ECU Protocol; wording clarification for technical compliance.
SM Committee) OE versus OEM Definitons #36608wordingwordingSMX Mazda Miata OE versus OEM definitions clarified in GCR Section 9.1.7.1.
SM Committee) Shifter Bushing #36611wordingwordingSM and SMX shifter bushing rules clarified: alternate bushing at shift lever bottom now allowed.
FP Errant entry in HP production line item #36231wordingwordingHP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in).
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.
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.
FP NIssan 300ZX Z31 to EP #35830cars addedcars addedNissan 300ZX 84-89 classified to EP at 2550 lbs minimum, 2960cc 6-cyl SOHC, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit.
FP RX7 1993 and Up Request In EP Spec Lines, classify #36031cars addedcars addedMazda RX-7 92-97 newly classified EP Prep Level 2 at 2200–2310 lbs with 13B 6-port rotary engine.
FP Clean-up Multiple EP RX-8 Spec Lines In EP #36156wordingwordingEP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains.
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.
FP Request to Replace CRX Plastic Panels #35876wordingwordingFP Honda CRX 84-87 can replace plastic front header, rocker skirt, door cap panels with stock-appearance replicas in alternate materials.
FP FP data and parity #35896inductionslowerFP Acura Integra and Honda Civic models now require 55mm Flat Plate Intake Restrictor.
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.
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
1:34.337Brad 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%)
1:42.620Danny Steyn · fastest of 47 · top 5 within 0.4s+0.001s (+0.00%)
1:42.995Charles Mactutus · fastest of 46 · top 5 within 0.1s+0.442s (+0.43%)
105.2Tyler Brown-6.9 mph (-6.2%)
+6.644squal +8.283s
106.9%qual 108.8%
1:37.924Ken Kannard · fastest of 4 · top 4 within 7.1s-0.418s (-0.43%)
1:37.623Ken Kannard · fastest of 5 · top 5 within 31.1s-0.945s (-0.96%)
119.0Ken Kannard-3.6 mph (-2.9%)
+1.272squal +3.587s
101.3%qual 103.8%
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%)
+23.914squal +9.964s
124.8%qual 110.6%
29 rule changes (FX: 3, FP: 18, AS: 8)7 cars added · 7 weight · 1 induction · 1 tyres & wheels · 13 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. · HP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve, Scirocco 1588. · FP Mazda Protégé ES (01-03) model designation updated to include /5 variant. · FX Formula 4 now complies with Table 1 notes only; removed reference to FIA 2015 technical regulations and FIA/SCCA safety requirements. · HP Honda Civic 1.5 (88-91) weight reduced to 2175 lbs base, 2229 lbs with power adder, 2284 lbs with two. · FP Acura Integra LS and Honda Del Sol VTEC minimum weights increase 25–78 lbs across all configurations. · EP BMW Z3 2.5L weight increases to 2500 lbs, 2563 lbs with turbo, 2625 lbs with supercharger. · FP Honda throttle body specs corrected: Civic 1.5 to 42", Si to 55", CRX variants adjusted. · EP Mazda MX-5 1.8L 1990-97 minimum weight drops to 2150 lbs; 1994-97 variants to 2000, 2050, 2100 lbs respectively. · EP Triumph GT6 dual 1.75" carbs weight drops to 1940 lbs; triple Weber 40 DCOE options consolidated. · EP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm. · EP Triumph TR8 dry sump allowance moved from carburetor line to notes section. · EP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs. · EP Porsche 944/924S combines 2.5L and 2.7L variants with new weights: 2250–2415 lbs depending on engine and year. · FP Toyota Corolla 2TC loses 43 lbs to 1810; HP Corolla loses 50–52 lbs to 1910–2006. · EP Triumph GT6 minimum weight reduced to 1800 lbs. · 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. · FP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44). · HP Volkswagen Rabbit Cabriolet 1780 removed; Rabbit 1588 and 1715 reclassified with engine sizes and year ranges specified. · Ford Fiesta HP and Chevrolet Sonic FP model year ranges extended from 2016 to 2019. · USF2000 Van Diemen with Mazda MZR LF-DE 2.0L added as spec line car in FC; removed from FX. · 1978-80 Toyota Celica classified FP Prep Level 2, 2100-2205 lbs, 2190cc SOHC, 11.0:1 compression, .450" valve lift max.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.
FP Update FP Protege (01-03) Model Info #35715wordingwordingFP Mazda Protégé ES (01-03) model designation updated to include /5 variant.
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.
FP Update 1988-1991 Civic to Match 1988-1991 CRX #35399weightfasterHP Honda Civic 1.5 (88-91) weight reduced to 2175 lbs base, 2229 lbs with power adder, 2284 lbs with two.
FP FP data #35060weight +25 lbsslowerFP Acura Integra LS and Honda Del Sol VTEC minimum weights increase 25–78 lbs across all configurations.
FP Request to Review Z3 2.5 Spec Line #35073weight +50 lbsslowerEP BMW Z3 2.5L weight increases to 2500 lbs, 2563 lbs with turbo, 2625 lbs with supercharger.
FP Corrections to Honda Spec Lines in FP #35250wordingunclearFP Honda throttle body specs corrected: Civic 1.5 to 42", Si to 55", CRX variants adjusted.
FP Miata Alternate Head #35253weight -50 lbsfasterEP Mazda MX-5 1.8L 1990-97 minimum weight drops to 2150 lbs; 1994-97 variants to 2000, 2050, 2100 lbs respectively.
FP Honda S2000 throttle body #35272inductionfasterEP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm.
FP Correction within Triumph TR8 Spec Line #35315wordingwordingEP Triumph TR8 dry sump allowance moved from carburetor line to notes section.
FP Correction to EP 924S/944 Spec Line #35317wordingwordingEP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs.
FP Porsche 944/924S Rule Change Request #35002cars addedcars addedEP Porsche 944/924S combines 2.5L and 2.7L variants with new weights: 2250–2415 lbs depending on engine and year.
FP FP and HP Toyota Corolla #35030weight -43 lbsfasterFP Toyota Corolla 2TC loses 43 lbs to 1810; HP Corolla loses 50–52 lbs to 1910–2006.
FX FM Rules Update #34841wordingunclearUnable to summarize: FX Formula Mazda spec changes reference attached document not provided.
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.
FP Correct Intake Valve Size on 1500cc Midget/Spitfire #34419wordingwordingFP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44).
FP ITC to FP? #34286cars addedcars addedHP Volkswagen Rabbit Cabriolet 1780 removed; Rabbit 1588 and 1715 reclassified with engine sizes and year ranges specified.
FP Request to Classify Sonic and Fiesta in HP #34264wordingwordingFord Fiesta HP and Chevrolet Sonic FP model year ranges extended from 2016 to 2019.
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.
FP Classification Request for 1978 Toyota Celica #34097cars addedcars added1978-80 Toyota Celica classified FP Prep Level 2, 2100-2205 lbs, 2190cc SOHC, 11.0:1 compression, .450" valve lift max.
Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST23MAR102023-03-10
1:42.619Charles Mactutus · fastest of 48 · top 5 within 0.7s-0.195s (-0.19%)
1:42.553Charles Mactutus · fastest of 47 · top 5 within 0.4s+0.689s (+0.68%)
112.2Jonathan Neudorf-1.3 mph (-1.2%)
1:38.342Mason Workman · fastest of 6 · top 5 within 8.5s-1.122s (-1.13%)
1:38.568Mason Workman · fastest of 6 · top 5 within 5.9s+0.177s (+0.18%)
122.6Mason Workman-3.9 mph (-3.1%)
26 rule changes (FX: 7, SM: 2, FP: 14, AS: 3)5 weight · 4 cars added · 2 engine · 2 induction · 1 aero · 1 tyres & wheels · 11 wording · FP Mazda Protégé ES (01-03) renamed to include P5 designation as Mazda Protégé ES/5 (01-03). · FX: Wording clarified to remove references to FB and FM in GCR section 1.4.2.D. · EP, FP, HP cylinder head ports limited to 1 inch maximum depth matching from mating surface. · SM Mazda MX-5 Miata 01-05 weight increases to 2450 lbs, or 2465 with alternate bore. · 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. · VW New Beetle 2.5L 5-cyl added to EP at 2400–2520 lbs, 2480 cc, fuel injection, comp ratio 12.0:1 max, valve lift 0.500" max. · EP Mazda RX-7 12A/13B gains fuel injection option on dual-y manifold with 42mm choke(s). · EP VW Corrado 92-95 stroke corrected to 90.3 mm, displacement to 2792 cc. · 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. · EP Subaru BRZ and Toyota 86/Scion FR-S model year ranges updated to 13-20. · FP Lotus Super Seven 91.7 ci minimum weight increases to 1580 lbs. · EP Mazda MX-5 Global Cup 16-22 minimum weight set to 2400 lbs; sequential gearbox allowed with +150 lbs penalty. · BMW 128i (08-13) classified in EP at 2700 lbs minimum with stock throttle body, 11.0:1 compression ratio, 0.400 in. valve lift limits. · EP/FP/HP open cars may now use carbon fiber hardtops if they retain OEM appearance in all exterior profiles. · Mazda Protégé ES 99-00 classified in FP at 2150–2258 lbs with 1839cc DOHC engine, fuel injection, 11.0:1 compression, .450" valve lift limit. · EP Mazda RX-8 13B carburetor rules clarified: dual 2bbl carb, fuel injected throttle body, or stock fuel injection permitted. · EP and FP Production clarifies idle control valve rules: stock devices allowed original, removed with blocked ports, or mechanical replaced with electronic stock type. · FP BMW 325e/es displacement corrected from 1647 to 2693 cc. · SM Majors must run authorized Penske shock and mount; Regional competitors' requirement eligibility clarified.showhide
FP Request to Add Mazda Protege P5 to FP #33664wordingwordingFP Mazda Protégé ES (01-03) renamed to include P5 designation as Mazda Protégé ES/5 (01-03).
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.
FP Review Limited Prep Port Matching Rules #33600wordingwordingEP, FP, HP cylinder head ports limited to 1 inch maximum depth matching from mating surface.
SM BOP for NB1 and NB2 #32309weightslowerSM Mazda MX-5 Miata 01-05 weight increases to 2450 lbs, or 2465 with alternate bore.
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.
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.
FP Request to classify VW New Beetle 2.5L in EP #32725cars addedcars addedVW New Beetle 2.5L 5-cyl added to EP at 2400–2520 lbs, 2480 cc, fuel injection, comp ratio 12.0:1 max, valve lift 0.500" max.
FP Request Rotary Injection on Dual Y manifold #32775inductionunclearEP Mazda RX-7 12A/13B gains fuel injection option on dual-y manifold with 42mm choke(s).
FP Request for Corrado Stroke & Displacement Correction #32985wordingwordingEP VW Corrado 92-95 stroke corrected to 90.3 mm, displacement to 2792 cc.
FX Pro Formula F2000/USF2000 Transmission E&O #32823engineslowerPro Formula F2000 tube frame reduced to 4 forward gears, sequential carries 25 lb. weight penalty.
FX Formula Mazda Minimum Weight #33010weightslowerFX Formula Mazda minimum weight exception set to 1270 lb.
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.
AS Request CTS-V Spec Line Error Correction #30242weightfasterAS Cadillac CTS-V 6.0L V8 removes 50 lbs weight penalty for 295 tire size.
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.
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.
FP Subaru BRZ Model Years #32500wordingwordingEP Subaru BRZ and Toyota 86/Scion FR-S model year ranges updated to 13-20.
FP Weight Adjustment of Lotus 7 #32213weight +50 lbsslowerFP Lotus Super Seven 91.7 ci minimum weight increases to 1580 lbs.
FP EP MX-5 Global Cup Car #32218weightslowerEP Mazda MX-5 Global Cup 16-22 minimum weight set to 2400 lbs; sequential gearbox allowed with +150 lbs penalty.
FP Please Class BMW 128i in EP #32370cars addedcars addedBMW 128i (08-13) classified in EP at 2700 lbs minimum with stock throttle body, 11.0:1 compression ratio, 0.400 in. valve lift limits.
FP Inconsistency in Body Work Descriptions #32396aerofasterEP/FP/HP open cars may now use carbon fiber hardtops if they retain OEM appearance in all exterior profiles.
FP Request to classify the 1999-2000 Mazda Protege in FP #32398cars addedcars addedMazda Protégé ES 99-00 classified in FP at 2150–2258 lbs with 1839cc DOHC engine, fuel injection, 11.0:1 compression, .450" valve lift limit.
FP Request Idle control valve clarification #32178wordingwordingEP and FP Production clarifies idle control valve rules: stock devices allowed original, removed with blocked ports, or mechanical replaced with electronic stock type.
FP Correct FP BMW 325e/es Displacement #32394wordingwordingFP BMW 325e/es displacement corrected from 1647 to 2693 cc.
SM Update GCR Section 9.1.7.3.A.1. #32217wordingwordingSM Majors must run authorized Penske shock and mount; Regional competitors' requirement eligibility clarified.
Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST22MAR122022-03-12
1:28.346Trent Walko · fastest of 4 · top 4 within 6.6s
1:25.399Trent Walko · fastest of 4 · top 4 within 5.7s
137.1Trent Walko
1:42.814Connor Zilisch · fastest of 60 · top 5 within 0.3s
1:41.864Travis Wiley · fastest of 60 · top 5 within 0.7s
113.5Junior Brock
+16.465squal +14.468s
119.3%qual 116.4%
1:39.464Perry Simonds · fastest of 5 · top 5 within 220.2s
1:38.391Perry Simonds · fastest of 5 · top 5 within 16.9s
126.5Ken Kannard
+12.992squal +11.118s
115.2%qual 112.6%
1:36.346Gregory Eaton · fastest of 3 · top 3 within 7.0s
1:35.993Gregory Eaton · fastest of 2
143.6Gregory Eaton
+10.594squal +8.000s
112.4%qual 109.1%
124 earlier rule changes on record, in force before Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta (from 2019)29 cars added · 18 weight · 10 engine · 8 suspension & brakes · 8 tyres & wheels · 5 induction · 44 wording · 2 other · EP BMW Z3 2.5L intake restrictor reduced from 59mm to 58mm flat plate. · Ford Mustang 99-03 classified to EP at 2700/2768/2835 lbs; 94-98 Mustang weight reduced to 2550/2614/2678 lbs. · EP, FP, HP Improved Touring cars may use any DOT-approved tire per section 9.3.45 in Production class. · FP VW Golf III/Jetta III 93-98 intake valve to 39.5/1.56, exhaust to 32.9/1.30. · EP, FP, HP classes allow stock/original idle control devices unmodified or completely removed with openings blocked. · 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. · EP Porsche 968 intake valve size increased from 37 to 39.0 mm. · EP, FP, HP front-wheel-drive cars may alter body and suspension to install alternate transmission, transaxle, and axle shaft. · EP BMW Z3 2.5L allows alternate throttle body from 92-95 325i with Turner adapter; head casting 1738400 permitted with specific blocks. · FP Honda Civic Del Sol VTEC removes restrictions on dry sump, connecting rods, intake manifold porting, crankshaft, rocker arms, cam followers. · FP Honda Prelude 84-87 and Mazda GLC/323 86-88 standardize valve lift measurement and remove Level 1 dry sump restrictions. · EP Porsche 944S2 89-91 requires 56mm flat plate intake restrictor; comp ratio max 12.0:1, valve lift max 0.500". · HP Corolla GTS RWD (84-87) added at 2300 lbs; HP Corolla FX16 FWD (87-88) added at 2260 lbs; old Corolla (84-87) removed. · 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. · HP Toyota MR-2 1.6L (85-89) track corrected to 15.47 inches front and rear. · Honda S2000 (00-03) reclassified as EP Prep with F22c engine option: 1997cc or 2157cc, weight 2450–2636 lbs depending on displacement. · EP Nissan 240-SX S13/S14 loses 200-210 lbs minimum weight; comp ratio rises to 12.0:1, valve lift to .500. · FX USF2000 Tube Frame allows Hoosier radials 20.5x7.0x13 front and 22.5x8.0x13 rear, FC-compliant shocks, Wilwood brakes, Bosch spark plugs. · EP Lotus/Caterham 7 America carburetor changed from IT fuel injection prep to fuel injection. · Plymouth Arrow 1598cc four-cylinder classified to HP at 1800 lbs minimum weight. · BMW 318i E30 (84-85) reclassified from FP to HP at 2200–2310 lbs with fuel injection and .425" valve lift limit. · FP Fiat X-1/9 1300 loses 50 lbs to 1665; X-1/9 loses 50 lbs to 1765. · Daimler SP 250 classified in EP at 2165 lbs with 2548 cc OHV 8-cylinder engine. · 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. · Porsche 924 moves from EP to FP Level 1 Prep, classified at 2200 lbs with 1984cc 4-cylinder OHC engine. · EP, FP, HP clarifies percentage weight penalties sum first, then apply to base weight, rounding to nearest pound. · FX USF2000 Tube Frame now allows any Hoosier radial tire 20.5x7.0x13 front, 22.5x8.0x13 rear. · 84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lbs weight, 1998cc SOHC, dual 32mm carbs. · FP Fiat X1/9 brake rotors change to 257 (10.1) x 12 (.407) solid disc. · FX adds 2000-2009 Formula Renault 2.0 / Fran-Am 2000 classified at 1250 lbs with sealed 2.0L Renault F4R 832 engine. · Mazda 3 S 04-08 classified in EP at 2350 lbs minimum, 2.26L DOHC, 12.0:1 compression, .500" valve lift limit. · FP Volkswagen Golf III and IV intake valves increase to 40.0 mm, exhaust valves to 33.0 mm. · SM adds procedures for testing obsolete part replacements and BOP updates in sanctioned events with CRB approval. · 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. · EP Austin-Healey 3000 Mk. I, II, III now allows TR-6 front calipers and discs as alternate. · FP Volkswagen Golf 1.8 (85-92), Jetta 1.8 (85-92) lose 50 lbs to 1900; Jetta (82-84), Rabbit, Scirocco lose 50-100 lbs to 1733-1803. · 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. · FP Volkswagen Golf and Jetta 1.8 lose 50 lbs each, to 1900. HP Jetta GLI engine code removed. · EP, FP, HP Level 1 and Level 2 induction systems: clarified carburetor and fuel injection rules, jets/needles/rods unrestricted in Level 2. · EP Datsun SRL 311U Roadster minimum weight reduced to 1925 lbs from 2000 lbs. · EP Triumph TR8 78-81 weight reduced from 2600 to 2500 lbs. · Honda Civic EX 96-00 classified in FP at 1975 lbs, 1590cc SOHC, 56mm throttle body, valve lift .450" max. · FP adds FAJS carburetor to permitted Weber and auto-type substitutions in two rule sections. · FX FormulaSPEED FS2.0 specification requirements updated; World Speed Inc. deadline removed, compliance now per SCCA website. · HP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches. · SM aftermarket radiators must mount in original location, maintain core plane, require no body modifications, block openings, keep one OEM fan in stock location; 1990-1997 cars may install upper radiator seal NA75-50-OK7A. · 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. · EP BMW Z3 2.5L iron block casting 1738566-C designation removed, wording clarification only. · SM rear brake calipers may use single bracket under upper retaining bolt to prevent pin failure. · 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. · Porsche 911 S 67-68 classified in EP at three weight levels: 1800, 1845, or 1890 lbs. · FP Mazda 626 84-87 carburetor spec now specifies two auto-type sidedraft 32mm choke carbs or fuel injection. · Formula Ireland/Formula FX car addition to FX Table 1 pending specification submission; not recommended. · EP BMW 2.8L, 328i E36/E46, and 325i E36 blocks now iron only; 325i E46 aluminum only. · FP Volkswagen Scirocco E&O adds four engine variants with weights 1520–1853 lbs and displacements 1471–1780 cc. · AS Chevrolet/Pontiac Camaro & Firebird (82-92) loses 50 lbs, to 3500. · 1990-1994 Mazda Protege classified in FP Pre at 2150–2258 lbs with 1839cc DOHC engine, fuel injection. · HP Mini Cooper model year ranges for convertibles revised: 02-06 now includes 05-08, 07-13 now includes 09-15. · EP Caterham 7 Spec Line removes redundant suspension note, clarifies engine prep limits and comp ratio to 10.0:1. · 1989-90 Nissan 240-SX SOHC added to FP Level 2 with 2400-2520 lbs weight range. · 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. · FP Volkswagen Jetta, Rabbit, Scirocco 1457-1853cc reclassified with inlet valve 40.0mm, exhaust 33.0mm, weights 1520-1853 lbs. · HP Datsun 510 gains 40 DCOE carburetor option alongside existing 40 DCN and 36mm DCNVH choices. · Porsche 914-4 2.0L classified in FP Prep 2 at 2030-2132 lbs with 1968cc OHV engine, 11.0:1 compression limit, .450" valve lift limit. · FP Ford Fiesta 78-80 weight reduced 130 lbs to 1660. · 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. · HP Datsun 1200 carburetor choke size increases from 26mm to 30mm. · Pro Formula F 2000 Tube Frame engine now must follow current FC rules with restricted ECU map, cams, and air restrictor required. · FP and EP Mazda Miata models standardized to 55mm throttle body diameter; brake spec clarified. · FP Mazda Protégé ES 01-03 newly classified at 2350–2468 lbs with 1991cc 4-cyl DOHC, fuel injection, 11.0:1 compression, .450 in. valve lift limit. · FP and HP Honda Civic and CRX 1988–91 track specifications corrected to 61.3/61.7 inches. · EP, FP, HP cylinder head rules reorganized for clarity; no performance change. · AS Spec Mustang (SMG) added as Restricted Prep class. · FP and HP Austin-Healey Sprite Mk I and MG Midget variants may replace rear bodywork aft of cockpit with stock-appearing alternate material components. · EP Mazda MX-5 Global Cup classification year changes from 16-18 to 16-19. · Production suspension rule clarifies spindles, hubs, bushings, bearings, ball joints unrestricted. · Production carb rules clarified: carburetor options, fuel injection throttle body dimensions, and intake manifold restrictions reorganised and refined. · EP, FP, HP carburetors clarified: jets, needles, metering rods, needle valves unrestricted; choke parts removable; permitted optional carburetors listed. · AS class minimum ride height clarified to 5 inches measured at rocker panel, excluding seams and cladding. · EP Mazda MX-5/Miata eligibility years expanded from 1999-2002 to 1999-2005. · AS Ford Mustang (79-93) 313 CID and under loses 100 lbs to 3150; over 313 CID loses 100 lbs to 3450. · EP, FP, HP clarified: tapered holes in ball joints now allowed for bolt conversion; wheel bearings and hubs unrestricted at any wheel. · EP open cars may now use aftermarket hardtops if they retain OEM appearance; specific model hardtop allowances removed. · FP Dodge Daytona/Chrysler Laser added at 2100/2153/2205 lbs; Shelby Charger/Omni 024 weight reduced to 2100/2153/2205 lbs. · SM fuel pump and filter must be Mazda or OEM Equivalent part. · AS Spec Mustang (SMG) newly classified with 107.1 wheelbase, 3.73 gears, 355mm front brakes, 300mm rear. · SM 1999-2000 model year cars may use replacement Mazda ECU and injector harnesses, unmodified. · SM electrical rules reorganized and clarified; alternator external regulation now prohibited except via OEM ECU/kill switch. · SM removes tire tread protrusion beyond fender opening requirement from GCR 9.1.7.C.5.showhide
FP EP Adjustments #31858inductionslowerEP BMW Z3 2.5L intake restrictor reduced from 59mm to 58mm flat plate.
FP 1999 3.8L Ford Mustang to EP? #31635weightfasterFord Mustang 99-03 classified to EP at 2700/2768/2835 lbs; 94-98 Mustang weight reduced to 2550/2614/2678 lbs.
FP Improved Touring Tires #32064tyres & wheelstyres & wheelsEP, FP, HP Improved Touring cars may use any DOT-approved tire per section 9.3.45 in Production class.
FP VW Golf Jetta 2.0L intake and exhaust size correction. #32173inductionslowerFP VW Golf III/Jetta III 93-98 intake valve to 39.5/1.56, exhaust to 32.9/1.30.
FP Throttle Body and Idle Air #31800wordingwordingEP, FP, HP classes allow stock/original idle control devices unmodified or completely removed with openings blocked.
FX FM Rule Set Clarification #31881wordingwordingFormula Mazda tire marking no longer required; compliance now referenced to updated online specifications document.
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.
FX E&O USF2000 Tube Frame #31951tyres & wheelsunclearFX USF2000 Tube Frame front tyre changes from radial to unspecified type, rear tyre options added.
FX URGENT - FX- Formula Renault Tire #32058tyres & wheelsfasterFX Formula Renault 2.0 (00-17) tire choice unrestricted; original components required except repairs.
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.
FP Porsche 968 Engine Questions #31478enginefasterEP Porsche 968 intake valve size increased from 37 to 39.0 mm.
FP PCS E. 2. n. 4. Add Axle Shaft to Allow FWD the Same Freedom #31592wordingwordingEP, FP, HP front-wheel-drive cars may alter body and suspension to install alternate transmission, transaxle, and axle shaft.
FP BMW Z3 2.5L Spec Line #31724wordingwordingEP BMW Z3 2.5L allows alternate throttle body from 92-95 325i with Turner adapter; head casting 1738400 permitted with specific blocks.
FP FP Del Sol VTEC #31859enginefasterFP Honda Civic Del Sol VTEC removes restrictions on dry sump, connecting rods, intake manifold porting, crankshaft, rocker arms, cam followers.
FP Standardize Level 2 Classifications in FP #31868wordingwordingFP Honda Prelude 84-87 and Mazda GLC/323 86-88 standardize valve lift measurement and remove Level 1 dry sump restrictions.
FP 944S2 Restrictor #31396inductionslowerEP Porsche 944S2 89-91 requires 56mm flat plate intake restrictor; comp ratio max 12.0:1, valve lift max 0.500".
FP Classing Clarification for 1986 Toyota Corolla FX16 #31527cars addedcars addedHP Corolla GTS RWD (84-87) added at 2300 lbs; HP Corolla FX16 FWD (87-88) added at 2260 lbs; old Corolla (84-87) removed.
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.
FP E&O; MR2 Track #31120wordingwordingHP Toyota MR-2 1.6L (85-89) track corrected to 15.47 inches front and rear.
FP Request to Allow F22c Engine for 2000-2003 Honda S2000 #30548cars addedunclearHonda S2000 (00-03) reclassified as EP Prep with F22c engine option: 1997cc or 2157cc, weight 2450–2636 lbs depending on displacement.
FP Request a review of the S14 240SX in EP. #30873weight -200 lbsfasterEP Nissan 240-SX S13/S14 loses 200-210 lbs minimum weight; comp ratio rises to 12.0:1, valve lift to .500.
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.
FP Lotus/Caterham 7 America Request #30392wordingunclearEP Lotus/Caterham 7 America carburetor changed from IT fuel injection prep to fuel injection.
FP Request to classify ITC Plymouth Arrow #30588cars addedcars addedPlymouth Arrow 1598cc four-cylinder classified to HP at 1800 lbs minimum weight.
FP Reclassification of the 1984/85 BMW 318i from FP to HP #30661cars addedcars addedBMW 318i E30 (84-85) reclassified from FP to HP at 2200–2310 lbs with fuel injection and .425" valve lift limit.
FP Fiat x1/9 Competition Adjustments #30711weight -50 lbsfasterFP Fiat X-1/9 1300 loses 50 lbs to 1665; X-1/9 loses 50 lbs to 1765.
FP Reclassify Daimler SP 250 #30721cars addedcars addedDaimler SP 250 classified in EP at 2165 lbs with 2548 cc OHV 8-cylinder engine.
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.
FP Move Porsche 924 in Level 1 Prep From EP to FP #30135cars addedcars addedPorsche 924 moves from EP to FP Level 1 Prep, classified at 2200 lbs with 1984cc 4-cylinder OHC engine.
FP Clarify Application of Percentage Based Weight Penalties #30669weightslowerEP, FP, HP clarifies percentage weight penalties sum first, then apply to base weight, rounding to nearest pound.
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.
FP Change Classification of 84-87 Mazda 626 from FP to HP #30350cars addedcars added84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lbs weight, 1998cc SOHC, dual 32mm carbs.
FP Fiat X1/9 brake rotors #30423suspension & brakessuspension & brakesFP Fiat X1/9 brake rotors change to 257 (10.1) x 12 (.407) solid disc.
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.
FP Please Classify Mazda3 in FP #30165cars addedcars addedMazda 3 S 04-08 classified in EP at 2350 lbs minimum, 2.26L DOHC, 12.0:1 compression, .500" valve lift limit.
FP Golf MkIII Valve Size Request #30268enginefasterFP Volkswagen Golf III and IV intake valves increase to 40.0 mm, exhaust valves to 33.0 mm.
SM Updates - Obsolete Parts & BOP Parts #30438wordingwordingSM adds procedures for testing obsolete part replacements and BOP updates in sanctioned events with CRB approval.
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.
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.
FP Alternate Front Brake Rotors and Calipers for EP AH 3000 #29893suspension & brakessuspension & brakesEP Austin-Healey 3000 Mk. I, II, III now allows TR-6 front calipers and discs as alternate.
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.
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.
FP Mk2 VW Consistency and Cleanup of FP and HP Spec Lines #29195weight -50 lbsfasterFP Volkswagen Golf and Jetta 1.8 lose 50 lbs each, to 1900. HP Jetta GLI engine code removed.
FP Correct Wording for Level 1 and Level 2 Induction Systems #29406wordingwordingEP, FP, HP Level 1 and Level 2 induction systems: clarified carburetor and fuel injection rules, jets/needles/rods unrestricted in Level 2.
FP Weight Reduction for Datsun Roadster #29409weight -75 lbsfasterEP Datsun SRL 311U Roadster minimum weight reduced to 1925 lbs from 2000 lbs.
FP EP TR8 Adjustment #29512weight -100 lbsfasterEP Triumph TR8 78-81 weight reduced from 2600 to 2500 lbs.
FP Request to Classify 1996-2000 Honda Civic EX #29515cars addedcars addedHonda Civic EX 96-00 classified in FP at 1975 lbs, 1590cc SOHC, 56mm throttle body, valve lift .450" max.
FP FAJS Carburetor #29576wordingwordingFP adds FAJS carburetor to permitted Weber and auto-type substitutions in two rule sections.
FX Update specifications for FormulaSPEED cars #29674wordingwordingFX FormulaSPEED FS2.0 specification requirements updated; World Speed Inc. deadline removed, compliance now per SCCA website.
FP 84-87 Toyota Corolla HP Wheel Diameter Allowance Proposal E&O #29458tyres & wheelsfasterHP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches.
SM Radiator E&O Clarifications #29294wordingwordingSM aftermarket radiators must mount in original location, maintain core plane, require no body modifications, block openings, keep one OEM fan in stock location; 1990-1997 cars may install upper radiator seal NA75-50-OK7A.
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.
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.
FP EP BMW Z3 Rule Clarification #28998wordingwordingEP BMW Z3 2.5L iron block casting 1738566-C designation removed, wording clarification only.
SM Modifications to prevent failures of Rear Brake Caliper Pin #28953suspension & brakessuspension & brakesSM rear brake calipers may use single bracket under upper retaining bolt to prevent pin failure.
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.
FP Request to Classify Porsche 911 2.0L #28456cars addedcars addedPorsche 911 S 67-68 classified in EP at three weight levels: 1800, 1845, or 1890 lbs.
FP Request to change to Carburetor Spec Line 84-87 Mazda 626 #28926wordingunclearFP Mazda 626 84-87 carburetor spec now specifies two auto-type sidedraft 32mm choke carbs or fuel injection.
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.
FP BMW Cylinder Head Casting and Part Numbers #28708engineslowerEP BMW 2.8L, 328i E36/E46, and 325i E36 blocks now iron only; 325i E46 aluminum only.
FP Correct Scirocco Spec line E&O #28892cars addedcars addedFP Volkswagen Scirocco E&O adds four engine variants with weights 1520–1853 lbs and displacements 1471–1780 cc.
AS weight adjustments for 2020 season #28785weight -50 lbsfasterAS Chevrolet/Pontiac Camaro & Firebird (82-92) loses 50 lbs, to 3500.
FP Request to Classify 1990-1994 Mazda Protege #28381cars addedcars added1990-1994 Mazda Protege classified in FP Pre at 2150–2258 lbs with 1839cc DOHC engine, fuel injection.
FP Error in Mini Cooper Spec Line #28713wordingwordingHP Mini Cooper model year ranges for convertibles revised: 02-06 now includes 05-08, 07-13 now includes 09-15.
FP Caterham 7 Spec Line #28498wordingwordingEP Caterham 7 Spec Line removes redundant suspension note, clarifies engine prep limits and comp ratio to 10.0:1.
FP Request to classify SOHC 1989-90 240SX in F prod L2 #28553cars addedcars added1989-90 Nissan 240-SX SOHC added to FP Level 2 with 2400-2520 lbs weight range.
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.
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.
FP Request to allow 40 DCOE carb for the Datsun 510 #28195inductionfasterHP Datsun 510 gains 40 DCOE carburetor option alongside existing 40 DCN and 36mm DCNVH choices.
FP Request to classify Porsche 914 2L in LPrep FProd #28231cars addedcars addedPorsche 914-4 2.0L classified in FP Prep 2 at 2030-2132 lbs with 1968cc OHV engine, 11.0:1 compression limit, .450" valve lift limit.
FP Request Ford Fiesta Weight Adjustment #28336weightfasterFP Ford Fiesta 78-80 weight reduced 130 lbs to 1660.
FX Request to remove tire marking language from FM #28415wordingwordingFX Formula Mazda no longer requires tire marking; must comply with December 2019 GCR rules.
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.
FP Request for Help for Datsun 1200 #27934inductionfasterHP Datsun 1200 carburetor choke size increases from 26mm to 30mm.
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.
FP Request to List Mazda Miata Throttle Body Size #27907wordingwordingFP and EP Mazda Miata models standardized to 55mm throttle body diameter; brake spec clarified.
FP Request to Classify 2001-2003 Mazda Protege ES in FP #27922cars addedcars addedFP Mazda Protégé ES 01-03 newly classified at 2350–2468 lbs with 1991cc 4-cyl DOHC, fuel injection, 11.0:1 compression, .450 in. valve lift limit.
FP Request to Correct Track of 1988-91 Honda Civic #27487wordingwordingFP and HP Honda Civic and CRX 1988–91 track specifications corrected to 61.3/61.7 inches.
FP Re-organize Prep2 Cylinder Head Rules for Clarity & Consistency #27661wordingwordingEP, FP, HP cylinder head rules reorganized for clarity; no performance change.
AS Request to add SMG to 9.1.6.B.1 AS Intent #27140cars addedcars addedAS Spec Mustang (SMG) added as Restricted Prep class.
FP Request bodywork for Austin Healey Bugeye Sprite MK1 #27106wordingwordingFP and HP Austin-Healey Sprite Mk I and MG Midget variants may replace rear bodywork aft of cockpit with stock-appearing alternate material components.
FP Request to classify the GMX5 2019 #27263wordingwordingEP Mazda MX-5 Global Cup classification year changes from 16-18 to 16-19.
FP Clarification of Carb Rules - Prep 1 #27300wordingwordingProduction carb rules clarified: carburetor options, fuel injection throttle body dimensions, and intake manifold restrictions reorganised and refined.
FP Clarification of Carb Rules - Prep 2 #27301wordingwordingEP, FP, HP carburetors clarified: jets, needles, metering rods, needle valves unrestricted; choke parts removable; permitted optional carburetors listed.
AS Request Ride Height Clarification #26598wordingwordingAS class minimum ride height clarified to 5 inches measured at rocker panel, excluding seams and cladding.
FP Request Miata Eligibility - 2003 #27121cars addedcars addedEP Mazda MX-5/Miata eligibility years expanded from 1999-2002 to 1999-2005.
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.
FP Rollcenter Correction Clarification #25873suspension & brakesfasterEP, FP, HP clarified: tapered holes in ball joints now allowed for bolt conversion; wheel bearings and hubs unrestricted at any wheel.
FP Hardtops #26476wordingwordingEP open cars may now use aftermarket hardtops if they retain OEM appearance; specific model hardtop allowances removed.
FP Request Classification of Dodge Daytona in F Production #26259cars added -150 lbsfasterFP Dodge Daytona/Chrysler Laser added at 2100/2153/2205 lbs; Shelby Charger/Omni 024 weight reduced to 2100/2153/2205 lbs.
SM Request to allow aftermarket fuel filters. #26370wordingwordingSM fuel pump and filter must be Mazda or OEM Equivalent part.
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.
SM Request 99-00 replacement Wire harnesses #25602wordingwordingSM 1999-2000 model year cars may use replacement Mazda ECU and injector harnesses, unmodified.
SM Organize and Clarify 9.1.7.C.1.o. #25913wordingwordingSM electrical rules reorganized and clarified; alternator external regulation now prohibited except via OEM ECU/kill switch.
SM Strike Tire Tread Language #26123wordingwordingSM removes tire tread protrusion beyond fender opening requirement from GCR 9.1.7.C.5.
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 FX" is the class's best as a share of FX'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 FX'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.