BoP Labbeta

BoP Lab / Buttonwillow Raceway Park

FP vs HP vs FC pace at Buttonwillow Raceway Park

Class · click a class to switch, + to compare alongside (up to 4)
Reference class · the others' laps as a share of this one's at the same event, so years compare despite weather; + a class above to measure against it
Track configuration

Quickest here: FP 1:55.440 Michael Lewis, Cal Club 2025 race · HP 2:03.082 Lee Fleming, Cal Club 2025 race · FC 1:45.137 Robert Armington, Cal Club 2026 qualifying

1:451:501:552:002:0565 rule changes between Cal Club 2025 and Cal Club 202665 ▾FP race best at Cal Club 2025: 1:55.440 (Michael Lewis)FP race best at Cal Club 2026: 1:57.587 (Michael Lewis)FP qualifying best at Cal Club 2025: 1:56.121 (Michael Lewis)FP qualifying best at Cal Club 2026: 1:58.084 (Steven Powers)HP race best at Cal Club 2025: 2:03.082 (Lee Fleming)HP race best at Cal Club 2026: 2:03.324 (Lee Fleming)HP qualifying best at Cal Club 2025: 2:06.770 (Lee Fleming)HP qualifying best at Cal Club 2026: 2:04.965 (Brian Linn)FC race best at Cal Club 2025: 1:48.522 (Paul MacFarlane)FC race best at Cal Club 2026: 1:45.314 (Robert Armington)FC qualifying best at Cal Club 2025: 1:50.067 (Paul MacFarlane)FC qualifying best at Cal Club 2026: 1:45.137 (Robert Armington)Cal Club 20252025Cal Club 20262026
FPHPFCsolid race · dashed qualifying · slower is lower
88%90%92%94%96%98%100%102%104%106%108%110%65 rule changes between Cal Club 2025 and Cal Club 202665 ▾FP race best at Cal Club 2025: 100.0% of FP's (Michael Lewis)FP race best at Cal Club 2026: 100.0% of FP's (Michael Lewis)FP qualifying best at Cal Club 2025: 100.0% of FP's (Michael Lewis)FP qualifying best at Cal Club 2026: 100.0% of FP's (Steven Powers)HP race best at Cal Club 2025: 106.6% of FP's (Lee Fleming)HP race best at Cal Club 2026: 104.9% of FP's (Lee Fleming)HP qualifying best at Cal Club 2025: 109.2% of FP's (Lee Fleming)HP qualifying best at Cal Club 2026: 105.8% of FP's (Brian Linn)FC race best at Cal Club 2025: 94.0% of FP's (Paul MacFarlane)FC race best at Cal Club 2026: 89.6% of FP's (Robert Armington)FC qualifying best at Cal Club 2025: 94.8% of FP's (Paul MacFarlane)FC qualifying best at Cal Club 2026: 89.0% of FP's (Robert Armington)Cal Club 20252025Cal Club 20262026
FPHPFCsolid race · dashed qualifying · each class's best lap as a share of FP's at the same event (the reference class, changeable above); 100% is level, higher is quicker
EventFPHPFC
Qual bestRace bestTrapQual bestRace bestTrapvs FP% of FPQual bestRace bestTrapvs FP% of FP
Cal Club 2026 CALCL262026-02-211:58.084Steven Powers · fastest of 2+1.963s (+1.69%)1:57.587Michael Lewis · fastest of 3 · top 3 within 2.1s+2.147s (+1.86%)137.8Daniel Snow+26.9 mph (+24.3%)2:04.965Brian Linn · fastest of 3 · top 3 within 4.8s-1.805s (-1.42%)2:03.324Lee Fleming · fastest of 3 · top 3 within 0.9s+0.242s (+0.20%)126.2Lee Fleming+25.8 mph (+25.7%)+5.737squal +6.881s104.9%qual 105.8%1:45.137Robert Armington · fastest of 4 · top 4 within 25.0s-4.930s (-4.48%)1:45.314Robert Armington · fastest of 4 · top 4 within 12.9s-3.208s (-2.96%)147.5Bill Wallschlaeger+33.0 mph (+28.9%)-12.273squal -12.947s89.6%qual 89.0%
65 rule changes (FP: 34, HP: 29, FC: 2)21 weight · 9 induction · 8 cars added · 8 engine · 1 tyres & wheels · 18 wording · 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. · HP Triumph Spitfire 1296cc compression ratio increases from 11.0 to 12.0:1. · FC USF2000 Tube Frame may use Hewland LD200 4-speed H-pattern as alternative to Hewland JL-200 5-speed sequential. · FC F2000 Metrik ZF2 minimum weight reduced to 1220 lbs. · HP Toyota MR-2 1.6L (85-89) compression ratio set to 11.0:1. · BMW 2002 newly classified to H Production at 2350 lbs with 1990cc iron block, 40 DCNF carburetor, 11.0:1 compression. · 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. · Datsun SPL-311 newly classified to HP at 2050 lbs with 1595cc OHV iron engine and specified carburetors. · 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. · HP Honda Civic and CRX models get wider 13-inch wheels: 6 to 7 inches. · 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. · 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 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. · 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. · 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. · 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. · 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. · HP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines. · HP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines. · 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. · 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. · 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 and 3-series models get smaller intake restrictors: Z3 2.5L to 52mm, Z3 2.8L to 55mm, 328i to 58mm, 325i to 56mm. · HP Mazda 2 11-14 base weight up 50 lbs to 2045; all VW 80s models up 50 lbs to 2150 base. · 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. · HP Mini Cooper 07-13 engine corrected to DOHC; valve lift limit reduced to 0.390 inches.showhide
  • FP Request Toyota 5E Series Engines #38208cars addedneutralFP class adds Toyota 5E DOHC 1497cc engine, 1900 lbs minimum weight, 23mm SIR induction.
  • FP Request for Toyota 4E Series Engines #38209cars addedneutralFP 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.
  • HP Triumph Spitfire 1296cc Compression Ratio Increase to 12:1 #39589enginefasterHP Triumph Spitfire 1296cc compression ratio increases from 11.0 to 12.0:1.
  • FC F2000 MZR Spec Line Clarity/Revision Requested #38927wordingneutralFC USF2000 Tube Frame may use Hewland LD200 4-speed H-pattern as alternative to Hewland JL-200 5-speed sequential.
  • FC Adjust F2000 Metrik ZF2 weight #39612weight -20 lbsfasterFC F2000 Metrik ZF2 minimum weight reduced to 1220 lbs.
  • HP E/O: Improve Consistency of the Spec Lines #39500engineunclearHP Toyota MR-2 1.6L (85-89) compression ratio set to 11.0:1.
  • HP Request to Reclassify BMW 2002 Into H Production #39567cars addedneutralBMW 2002 newly classified to H Production at 2350 lbs with 1990cc iron block, 40 DCNF carburetor, 11.0:1 compression.
  • 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 Competition Adjustment Request #39259weight -80 lbsfasterFP Lancia Scorpion minimum weight drops 80 lbs, to 1950.
  • FP Factory Roll Bar Removal on VW Convertible #39268wordingneutralFP 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.
  • HP Request to Re-Classsify Datsun SPL-311 to HP from FP #39116cars addedneutralDatsun SPL-311 newly classified to HP at 2050 lbs with 1595cc OHV iron engine and specified carburetors.
  • HP TR2 Notes E&O #39180wordingunclearEP Triumph TR2-TR4A allows 5-speed gearbox without overdrive; removes Weber carb and weight specification.
  • HP 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.
  • HP Alternative BOP Request for 84-87 Honda CRX/Civic #39223tyres & wheelsfasterHP Honda Civic and CRX models get wider 13-inch wheels: 6 to 7 inches.
  • 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 Weight Break for 1098 Midget / Sprite #38970weight -80 lbsfasterHP Austin-Healey Sprite/Midget 1098cc minimum weight drops 80 lbs to 1550.
  • 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 addedneutralFP 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 #39019wordingneutralFP 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 #39025wordingneutralEP, 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 #39130wordingneutralEP 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.
  • HP Please Lower Weight of 280Z #38871weight -160 lbsfasterEP Nissan 280Z minimum weight reduced from 2560 to 2400 lbs.
  • HP Miata Weight Adjustment Follow Up #38949weight -25 lbsfasterEP Mazda MX-5 1.8L 90-97 weight reduced to 2125 lbs from 2150 lbs.
  • HP Weight Break for 1098 Midget / Sprite #38970weight -80 lbsfasterHP Austin-Healey Sprite/Midget 1098cc minimum weight drops 80 lbs to 1550.
  • HP HP Volvo 142 spec omission #38994engineslowerHP Volvo 142/142E gains compression ratio limit 12.0:1 and valve lift limit .425".
  • HP HP Mini DOHC 1.6 #38996engineslowerHP Mini Cooper 07-15 valve lift reduced to .390", from .450".
  • HP Add to Rabbit description #39019wordingneutralFP and HP Volkswagen Rabbit descriptions updated: Convertible changed to Cabriolet in FP; Cabriolet added to three HP engine variants.
  • HP Clean-up 9.1.5.E.7e #39025wordingneutralEP, FP, HP: rear drum brake to disc conversion clarified; rotors solid, diameter limited to largest front rotor permitted.
  • HP Add TB size to Ford Mustang (94-98) Spec Line #39130wordingneutralEP Ford Mustang (94-98) fuel injected throttle body inside diameter specified at 60.
  • FP HP Plymouth Arrow spec omission #38995wordingneutralHP Plymouth Arrow transmission max speeds clarified to 4 or 5.
  • FP Add Wheel Diameter to Appendix G #39008wordingneutralEP, FP, HP wheel diameter added to Appendix G as absolute maximum specification.
  • FP Add TB ID tolerance to general Prod rules #39009wordingneutralEP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only.
  • HP HP Plymouth Arrow spec omission #38995wordingneutralHP Plymouth Arrow transmission max speeds clarified to 4 or 5.
  • HP Add Wheel Diameter to Appendix G #39008wordingneutralEP, FP, HP wheel diameter added to Appendix G as absolute maximum specification.
  • HP Add TB ID tolerance to general Prod rules #39009wordingneutralEP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only.
  • 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.
  • HP BMW Z4 update #38490inductionslowerEP BMW Z4 03-05 restricted to 52mm flat plate intake restrictor.
  • HP 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.
  • 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.
  • HP 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.
  • FP Request for Classification of Chevrolet Spark #37755cars addedneutralChevrolet 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.
  • HP Request for Classification of Chevrolet Spark #37755cars addedneutralChevrolet Spark 16-22 classified HP Pre at 1850 lbs minimum weight, fuel injected, 1399 cc.
  • HP 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.
  • 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 #37235wordingneutralEP, 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 addedneutralFP GTL Volkswagen Jetta Mark IV 4dr FWD 98.2 wheelbase newly classified.
  • FP GTL/FP consolidation 2025 Rules #37659inductionneutralFP Spec Lines option: carburettor chokes permitted as alternative to SIR, same size as listed SIR.
  • HP 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.
  • HP HP Class Adjustments #37459weight +50 lbsslowerHP Mazda 2 11-14 base weight up 50 lbs to 2045; all VW 80s models up 50 lbs to 2150 base.
  • HP Interpretation of Production Rules on Mirrors #37235wordingneutralEP, FP, HP: interior or exterior mirrors meeting rule 9.3.36 now permitted.
  • HP Weight Reduction for Honda S2000 #37466weightfasterEP Honda S2000 1997cc base loses 75 lbs to 2375; 2157cc base loses 60 lbs to 2450.
  • HP 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.
  • HP MINI Cooper (07-13) Spec Line Correction: Errors and Omissions #37560engineslowerHP Mini Cooper 07-13 engine corrected to DOHC; valve lift limit reduced to 0.390 inches.
Cal Club 2025 CALCL252025-02-221:56.121Michael Lewis · fastest of 5 · top 5 within 25.2s1:55.440Michael Lewis · fastest of 6 · top 5 within 10.7s110.9Michael Lewis2:06.770Lee Fleming · fastest of 4 · top 4 within 4.3s2:03.082Lee Fleming · fastest of 5 · top 5 within 6.2s100.4Lee Fleming+7.642squal +10.649s106.6%qual 109.2%1:50.067Paul MacFarlane · only car1:48.522Paul MacFarlane · only car114.4Paul MacFarlane-6.918squal -6.054s94.0%qual 94.8%
237 earlier rule changes on record, in force before Cal Club 2025 (from 2019)52 cars added · 48 weight · 18 induction · 11 engine · 9 suspension & brakes · 5 tyres & wheels · 2 aero · 92 wording · 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. · 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. · 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. · EP BMW 325i/is E30 (84-91) weight reduced 50–52 lbs across three spec lines to 2150, 2204, 2258. · HP Honda Civic 1.5 88-91 weight reduced to 2175 lbs base, 2229 lbs with one asterisk, 2284 lbs with two asterisks. · HP Mini Cooper 02-06 rear brake rotor increases from 239/9.4 mm/in to 259/10.2. · FC tire limit reduced to four dry and four wet for Regional/Major/Super Tour, eight for Runoffs. · FF and FC cars with sequential gearbox must add 10 lbs. to minimum weight, down from 25 lbs. · HP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1. · HP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1. · Suzuki Swift GT 89-94 newly classified to HP Pre at 1900 lbs, 1298cc DOHC fuel injected. · FP Honda CRX/CRX Si 84-87 block material changes from Iron to Alum. · HP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in). · HP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in). · 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. · 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. · 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. · HP Honda CRX/Si 84-87 plastic panels can be replaced with replica alternate material if stock appearance maintained. · FC adds F2000 Metrik ZF2 with Ford Zetec engine and four-piston Brembo calipers as spec-line car. · 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. · HP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve, Scirocco 1588. · HP Honda Civic 1.5 (88-91) weight reduced to 2175 lbs base, 2229 lbs with power adder, 2284 lbs with two. · HP Honda Civic 1.5 (88-91) weight reduced to 2175 lbs base, 2229 lbs with power adder, 2284 lbs with two. · F600 Rotax 494, 493, 593 engines now require single expansion chamber and pull starter; electric starter optional. · 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 BMW Z3 2.5L weight increases to 2500 lbs, 2563 lbs with turbo, 2625 lbs with supercharger. · HP Sprite/Midget Mk I–IV, Mk 1500 compression ratio raised to 12.0:1 at Prep Level 1/2. · HP Triumph Spitfire 1500 valve spec changes from 36.6/5.5/(1.44/0) to 36.6/(1.44). · 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. · HP Honda CRX/Si 84-87 front header/nose panel may use alternate material if appearance remains stock. · 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. · HP Mazda 2 (11-14) minimum weight increases to 1995 lbs, 2045 lbs with*, 2095 lbs with**. · 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. · HP Honda CRX 1.5 (88-91) weight reduced to 2175 lbs, 2229 lbs, and 2284 lbs across three spec lines. · 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. · HP Mazda 626 84-87 weight reduced to 2200 lbs, 2255 lbs, and 2310 lbs across three configurations. · EP Triumph GT6 minimum weight reduced to 1800 lbs. · HP Nissan/Datsun PL510 carburetors allow larger 4mm chokes, replacing 2mm specification. · FC tire marking rule clarified: four dry and wet tires for Regionals, eight each for Runoffs; damaged tire replacement procedures revised. · 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. · 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. · USF2000 Van Diemen with Mazda MZR LF-DE 2.0L added as spec line car in FC; removed from FX. · Ford Fiesta HP and Chevrolet Sonic FP model year ranges extended from 2016 to 2019. · Ford Fiesta HP and Chevrolet Sonic FP model year ranges extended from 2016 to 2019. · 1978-80 Toyota Celica classified FP Prep Level 2, 2100-2205 lbs, 2190cc SOHC, 11.0:1 compression, .450" valve lift max. · FP Mazda Protégé ES (01-03) renamed to include P5 designation as Mazda Protégé ES/5 (01-03). · FC/FF PE3-8400 ECU monitor firmware version reduced from V3.04.50 to V3.04.35. · EP, FP, HP cylinder head ports limited to 1 inch maximum depth matching from mating surface. · MGB & MGB-GT HP weight breaks reduced to 2000, 2050, 2100 lbs; new MGB HP Prep 1/2 hybrid added at 2175 lbs. · HP Nissan/Datsun PL510 weight reduced: base 1960 to 1910 lbs, * 2009 to 1958 lbs, ** 2058 to 2006 lbs. · EP, FP, HP cylinder head ports limited to 1 inch maximum depth matching from mating surface. · 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. · 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. · FC Ford Zetec Performance Electronics ECU model renamed PE-3 to PE3-8400; Monitor firmware updated to V3.04.50. · EP Subaru BRZ and Toyota 86/Scion FR-S model year ranges updated to 13-20. · 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 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. · 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. · 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. · HP Volkswagen New Beetle (98-05) classified at 2350 lbs minimum, 1984cc SOHC, fuel injection, 11.0:1 compression limit. · 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. · HP Triumph Spitfire 1500 minimum weight increases to 1605 lbs, 1645 lbs, or 1685 lbs. · 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. · EP, FP, HP classes allow stock/original idle control devices unmodified or completely removed with openings blocked. · EP, FP, HP classes allow stock/original idle control devices unmodified or completely removed with openings blocked. · HP Fiat X1/9 intake valves corrected to 36.3mm/1.43in; exhaust valves to 33.3mm/1.31in or 31.2mm/1.23in depending on level. · FC chassis/frame section reorganized: anti-intrusion panels between main tubes clarified, suspension mounting restrictions strengthened, firewall requirements reworded. · 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 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. · HP Fiat X1/9 1500 loses 50 lbs to 1950; 1300 loses 45–47 lbs; Bertone 1500 loses 50–52 lbs. · Austin-Healey Sprite Mk I, II, III, IV and MG Midget classified in HP Prep with 1510–1586 lbs depending on prep level. · EP BMW Z3 2.5L allows alternate throttle body from 92-95 325i with Turner adapter; head casting 1738400 permitted with specific blocks. · Austin-Healey Sprite Mk I–IV and MG Midget classified in HP with 1655 lbs minimum weight. · FC Zetec ECU requirements clarified: Pectel T2 or Performance PE-3 required with specific communications ports and SCCA tune-file/map. · 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. · 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. · FC composite anti-intrusion panels of non-uniform thickness limited to eight fasteners per side. · FC tire marking rules clarified: competitor responsible for declaring, marking, and logging tires with Tech before qualifying or race. · HP Toyota MR-2 1.6L (85-89) track corrected to 15.47 inches front and rear. · 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. · 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. · 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. · 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. · Daimler SP 250 classified in EP at 2165 lbs with 2548 cc OHV 8-cylinder engine. · 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. · HP Spec Line Porsche 924 (76-84) brakes change from solid to vented disc. · EP, FP, HP clarifies percentage weight penalties sum first, then apply to base weight, rounding to nearest pound. · HP Mazda 626 (84-87) induction changed from dual 32mm sidedraft carbs to carburation or fuel injection. · 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. · Volvo 142/142E moves from HP Spec P-1800 Engine to HP Prep with 1989cc OHV four-cylinder, 2450–2573 lbs. · Volkswagen Golf III/Jetta III 93-98 classified to HP at 2325–2441 lbs with 1984cc SOHC engine. · Porsche 924 (76-84) newly classified to HP with 2400-2520 lbs weight, fuel injection, 1984cc engine. · 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. · 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. · HP Mini Cooper classification expands to include 12-15 Coupe model in existing spec line. · HP Volkswagen Rabbit GTI 1780 (83-84) permits Mk2 VW front spindles, hubs and bearings. · FC Pinto engine loses 10 lbs to 1190; Pinto aluminum head loses 10 lbs to 1190; Zetec loses 10 lbs to 1210. · 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. · EP Austin-Healey 3000 Mk. I, II, III now allows TR-6 front calipers and discs as alternate. · 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. · 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. · FC: Pectel T2 and Performance PE-3 ECU maps clarified; SCCA Club or 2013 Pro map required. · HP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches. · HP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches. · FC Zetec engine minimum weight increases 20 lbs to 1220 lbs. · EP BMW Z3 2.5L iron block casting 1738566-C designation removed, wording clarification only. · EP BMW Z3 2.5L iron block casting 1738566-C designation removed, wording clarification only. · 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. · Porsche 911 S 67-68 classified in EP at three weight levels: 1800, 1845, or 1890 lbs. · 1.8 VW GTI Mk1 dual carb request denied; remains stock fuel injection only. · 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. · EP BMW 2.8L, 328i E36/E46, and 325i E36 blocks now iron only; 325i E46 aluminum only. · 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. · 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. · EP Caterham 7 Spec Line removes redundant suspension note, clarifies engine prep limits and comp ratio to 10.0:1. · 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. · HP Volkswagen Rabbit and Scirocco 1588 remove 32mm choke requirement, clarify carburetor options and weight penalties. · HP Mini Cooper Convertible (07-13) newly classified; (05-08) convertible spec consolidated into main listing. · HP Datsun 510 Level 2 brakes changed from factory spec to 9.1 disc front, 9.0 drum rear, allowing 240Z/260Z/280Z parts. · HP Datsun 510 gains 40 DCOE carburetor option alongside existing 40 DCN and 36mm DCNVH choices. · HP Ford Fiesta 78-80 minimum weight drops 50 lbs to 1725; both asterisk tiers drop 51 lbs. · HP Datsun 1200 carburetor choke size increases from 26mm to 30mm. · HP Datsun 1200 carburetor choke size increases from 26mm to 30mm. · 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. · HP Mazda2 updates to 11-14, Honda Fit to 15-19, Mini Cooper to 07-13. · HP Porsche 914-4 1.8L now allows 2-stage dry sump if cam-driven and OEM-located. · HP Toyota Corolla 71-74 permitted to use rear axle housing from 84-87 Corolla. · FP and EP Mazda Miata models standardized to 55mm throttle body diameter; brake spec clarified. · HP VW Rabbit Convertible and Scirocco 1.6L lose 50 lbs minimum weight, to 1735. · FC Zetec connecting rods now allow Eagle #CRS5483F3D in addition to original Ford. · FC adds Mahle #930169439 piston as alternate option to existing Ford, Sealed Power, and United Engine choices. · 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. · 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. · 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. · 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. · EP Mazda MX-5/Miata eligibility years expanded from 1999-2002 to 1999-2005. · EP Mazda MX-5/Miata eligibility years expanded from 1999-2002 to 1999-2005. · FC Wiseco piston and Crower connecting rod part numbers updated; minimum weight 976 grams. · 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. · 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. · HP Toyota Yaris 06-11, 07-12 sedan, 12-18 add 130-136 lbs minimum weight. · HP Ford Fiesta years corrected to 11-16; Mazda hubs D651-33-06 front and D651-26-15XE rear allowed. · FC Wiseco piston and Crower connecting rod assembly minimum weight increases from 555 to 976 grams.showhide
  • 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.
  • HP 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.
  • 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 #37437wordingneutralFP 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 addedneutralF Production now allows GT-Lite cars meeting Appendix N specifications to compete, effective 2025-01-01.
  • HP 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.
  • HP Request to Update 1988-1991 Civic to Match 1988-1991 CRX #37444weight -70 lbsfasterHP Honda Civic 1.5 88-91 weight reduced to 2175 lbs base, 2229 lbs with one asterisk, 2284 lbs with two asterisks.
  • HP MINI Cooper Spec Line Correction - Rear Brake Rotor Diameter #37176suspension & brakesneutralHP Mini Cooper 02-06 rear brake rotor increases from 239/9.4 mm/in to 259/10.2.
  • FC 9.1.1.10.h. FC Tire Rule #36533tyres & wheelsslowerFC tire limit reduced to four dry and four wet for Regional/Major/Super Tour, eight for Runoffs.
  • FC Change FF/FC Weight with Sequential Gearbox #36651weightfasterFF and FC cars with sequential gearbox must add 10 lbs. to minimum weight, down from 25 lbs.
  • FP 1275 HP Spridget Level 2 Only #36518enginefasterHP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1.
  • HP 1275 HP Spridget Level 2 Only #36518enginefasterHP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1.
  • HP Request for Classification of 1989-1994 Suzuki Swift GT 16V Twin #36858cars addedneutralSuzuki Swift GT 89-94 newly classified to HP Pre at 1900 lbs, 1298cc DOHC fuel injected.
  • FP Errors/emissions Honda Civic/CRX #36700enginefasterFP Honda CRX/CRX Si 84-87 block material changes from Iron to Alum.
  • FP Errant entry in HP production line item #36231wordingneutralHP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in).
  • HP Errant entry in HP production line item #36231wordingneutralHP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in).
  • FP NIssan 300ZX Z31 to EP #35830cars addedneutralNissan 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 addedneutralMazda 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 #36156wordingneutralEP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains.
  • HP NIssan 300ZX Z31 to EP #35830cars addedneutralNissan 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.
  • HP RX7 1993 and Up Request In EP Spec Lines, classify #36031cars addedneutralMazda RX-7 92-97 newly classified EP Prep Level 2 at 2200–2310 lbs with 13B 6-port rotary engine.
  • HP Clean-up Multiple EP RX-8 Spec Lines In EP #36156wordingneutralEP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains.
  • FP Request to Replace CRX Plastic Panels #35876wordingneutralFP 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.
  • HP Replace plastic panels #35875wordingneutralHP Honda CRX/Si 84-87 plastic panels can be replaced with replica alternate material if stock appearance maintained.
  • FC Four Pot Calipers #35481cars addedneutralFC adds F2000 Metrik ZF2 with Ford Zetec engine and four-piston Brembo calipers as spec-line car.
  • FP GCR Correction - Redundant HP Spec Lines #35623wordingneutralHP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve, Scirocco 1588.
  • FP Update FP Protege (01-03) Model Info #35715wordingneutralFP Mazda Protégé ES (01-03) model designation updated to include /5 variant.
  • HP GCR Correction - Redundant HP Spec Lines #35623wordingneutralHP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve, Scirocco 1588.
  • 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.
  • HP 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.
  • FC Please correct omitted punctuation #34890engineneutralF600 Rotax 494, 493, 593 engines now require single expansion chamber and pull starter; electric starter optional.
  • 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 Triumph GT6 Adjustments #35255weightfasterEP Triumph GT6 dual 1.75" carbs weight drops to 1940 lbs; triple Weber 40 DCOE options consolidated.
  • 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 #35315wordingneutralEP Triumph TR8 dry sump allowance moved from carburetor line to notes section.
  • FP Correction to EP 924S/944 Spec Line #35317wordingneutralEP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs.
  • HP 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.
  • HP Parity in HP #35138enginefasterHP Sprite/Midget Mk I–IV, Mk 1500 compression ratio raised to 12.0:1 at Prep Level 1/2.
  • HP Spitfire classification #35224wordingunclearHP Triumph Spitfire 1500 valve spec changes from 36.6/5.5/(1.44/0) to 36.6/(1.44).
  • HP 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.
  • HP Triumph GT6 Adjustments #35255weightfasterEP Triumph GT6 dual 1.75" carbs weight drops to 1940 lbs; triple Weber 40 DCOE options consolidated.
  • HP Honda S2000 throttle body #35272inductionfasterEP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm.
  • HP Front Header/Nose Panel Alternate Material For 84-87 CRX #35301wordingneutralHP Honda CRX/Si 84-87 front header/nose panel may use alternate material if appearance remains stock.
  • HP Correction within Triumph TR8 Spec Line #35315wordingneutralEP Triumph TR8 dry sump allowance moved from carburetor line to notes section.
  • HP Correction to EP 924S/944 Spec Line #35317wordingneutralEP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs.
  • HP Review Classification of HP Mazda 2 #35318weight +75 lbsslowerHP Mazda 2 (11-14) minimum weight increases to 1995 lbs, 2045 lbs with*, 2095 lbs with**.
  • FP Porsche 944/924S Rule Change Request #35002cars addedneutralEP 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.
  • FP Triumph GT6 Adjustments #35054weight -30 lbsfasterEP Triumph GT6 minimum weight reduced to 1800 lbs.
  • HP Request to Adjust Weight of 1988-1991 CRX/Civic #35115weight -70 lbsfasterHP Honda CRX 1.5 (88-91) weight reduced to 2175 lbs, 2229 lbs, and 2284 lbs across three spec lines.
  • HP Porsche 944/924S Rule Change Request #35002cars addedneutralEP Porsche 944/924S combines 2.5L and 2.7L variants with new weights: 2250–2415 lbs depending on engine and year.
  • HP 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.
  • HP Weight Reduction for Mazda 626 #35031weight -100 lbsfasterHP Mazda 626 84-87 weight reduced to 2200 lbs, 2255 lbs, and 2310 lbs across three configurations.
  • HP Triumph GT6 Adjustments #35054weight -30 lbsfasterEP Triumph GT6 minimum weight reduced to 1800 lbs.
  • HP Larger chokes #34681inductionfasterHP Nissan/Datsun PL510 carburetors allow larger 4mm chokes, replacing 2mm specification.
  • FC Review FC Runoffs Tire Marking Rule #34274wordingneutralFC tire marking rule clarified: four dry and wet tires for Regionals, eight each for Runoffs; damaged tire replacement procedures revised.
  • FP Correct Intake Valve Size on 1500cc Midget/Spitfire #34419wordingneutralFP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44).
  • FP ITC to FP? #34286cars addedneutralHP Volkswagen Rabbit Cabriolet 1780 removed; Rabbit 1588 and 1715 reclassified with engine sizes and year ranges specified.
  • HP Correct Intake Valve Size on 1500cc Midget/Spitfire #34419wordingneutralFP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44).
  • HP ITC to FP? #34286cars addedneutralHP Volkswagen Rabbit Cabriolet 1780 removed; Rabbit 1588 and 1715 reclassified with engine sizes and year ranges specified.
  • FC USF2000 Van Diemen with Mazda MZR LF-DE 2.0L in FC #34329cars addedneutralUSF2000 Van Diemen with Mazda MZR LF-DE 2.0L added as spec line car in FC; removed from FX.
  • FP Request to Classify Sonic and Fiesta in HP #34264wordingneutralFord Fiesta HP and Chevrolet Sonic FP model year ranges extended from 2016 to 2019.
  • HP Request to Classify Sonic and Fiesta in HP #34264wordingneutralFord Fiesta HP and Chevrolet Sonic FP model year ranges extended from 2016 to 2019.
  • FP Classification Request for 1978 Toyota Celica #34097cars addedneutral1978-80 Toyota Celica classified FP Prep Level 2, 2100-2205 lbs, 2190cc SOHC, 11.0:1 compression, .450" valve lift max.
  • FP Request to Add Mazda Protege P5 to FP #33664wordingneutralFP Mazda Protégé ES (01-03) renamed to include P5 designation as Mazda Protégé ES/5 (01-03).
  • FC E&O 9.1.1.B.16.j #33634wordingunclearFC/FF PE3-8400 ECU monitor firmware version reduced from V3.04.50 to V3.04.35.
  • FP Review Limited Prep Port Matching Rules #33600wordingneutralEP, FP, HP cylinder head ports limited to 1 inch maximum depth matching from mating surface.
  • HP MGB HP Weight Break and/or Hybrid 1/2 Prep in HP #33127weightfasterMGB & MGB-GT HP weight breaks reduced to 2000, 2050, 2100 lbs; new MGB HP Prep 1/2 hybrid added at 2175 lbs.
  • HP Datsun 510 Help #33568weight -50 lbsfasterHP Nissan/Datsun PL510 weight reduced: base 1960 to 1910 lbs, * 2009 to 1958 lbs, ** 2058 to 2006 lbs.
  • HP Review Limited Prep Port Matching Rules #33600wordingneutralEP, FP, HP cylinder head ports limited to 1 inch maximum depth matching from mating surface.
  • FP Request to classify VW New Beetle 2.5L in EP #32725cars addedneutralVW 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 #32985wordingneutralEP VW Corrado 92-95 stroke corrected to 90.3 mm, displacement to 2792 cc.
  • HP Request to classify VW New Beetle 2.5L in EP #32725cars addedneutralVW 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.
  • HP 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).
  • HP Request for Corrado Stroke & Displacement Correction #32985wordingneutralEP VW Corrado 92-95 stroke corrected to 90.3 mm, displacement to 2792 cc.
  • FC Add Specification to Performance Electronics ECU for Ford Zetec #32761wordingneutralFC Ford Zetec Performance Electronics ECU model renamed PE-3 to PE3-8400; Monitor firmware updated to V3.04.50.
  • FP Subaru BRZ Model Years #32500wordingneutralEP Subaru BRZ and Toyota 86/Scion FR-S model year ranges updated to 13-20.
  • HP Subaru BRZ Model Years #32500wordingneutralEP 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 addedneutralBMW 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 addedneutralMazda 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.
  • HP 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.
  • HP Please Class BMW 128i in EP #32370cars addedneutralBMW 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.
  • HP 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 Mazda RX8 with 13b Rotary #32170wordingneutralEP Mazda RX-8 13B carburetor rules clarified: dual 2bbl carb, fuel injected throttle body, or stock fuel injection permitted.
  • FP Request Idle control valve clarification #32178wordingneutralEP 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 #32394wordingneutralFP BMW 325e/es displacement corrected from 1647 to 2693 cc.
  • HP Mazda RX8 with 13b Rotary #32170wordingneutralEP Mazda RX-8 13B carburetor rules clarified: dual 2bbl carb, fuel injected throttle body, or stock fuel injection permitted.
  • HP Request Idle control valve clarification #32178wordingneutralEP and FP Production clarifies idle control valve rules: stock devices allowed original, removed with blocked ports, or mechanical replaced with electronic stock type.
  • HP Classify VW New Beetle in HP. #32241cars addedneutralHP Volkswagen New Beetle (98-05) classified at 2350 lbs minimum, 1984cc SOHC, fuel injection, 11.0:1 compression limit.
  • 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 & wheelsneutralEP, 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.
  • HP Weight Change for Competition Adjustment #31182weight +45 lbsslowerHP Triumph Spitfire 1500 minimum weight increases to 1605 lbs, 1645 lbs, or 1685 lbs.
  • HP EP Adjustments #31858inductionslowerEP BMW Z3 2.5L intake restrictor reduced from 59mm to 58mm flat plate.
  • HP 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.
  • HP Improved Touring Tires #32064tyres & wheelsneutralEP, FP, HP Improved Touring cars may use any DOT-approved tire per section 9.3.45 in Production class.
  • FP Throttle Body and Idle Air #31800wordingneutralEP, FP, HP classes allow stock/original idle control devices unmodified or completely removed with openings blocked.
  • HP Throttle Body and Idle Air #31800wordingneutralEP, FP, HP classes allow stock/original idle control devices unmodified or completely removed with openings blocked.
  • HP Incorrect Valve Size Changes in Jan 2022 GCR for FIAT X1/9 #31990wordingunclearHP Fiat X1/9 intake valves corrected to 36.3mm/1.43in; exhaust valves to 33.3mm/1.31in or 31.2mm/1.23in depending on level.
  • FC Clean up Chassis/Frame section #31867wordingneutralFC chassis/frame section reorganized: anti-intrusion panels between main tubes clarified, suspension mounting restrictions strengthened, firewall requirements reworded.
  • 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 #31592wordingneutralEP, 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 #31724wordingneutralEP 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 #31868wordingneutralFP Honda Prelude 84-87 and Mazda GLC/323 86-88 standardize valve lift measurement and remove Level 1 dry sump restrictions.
  • HP Porsche 968 Engine Questions #31478enginefasterEP Porsche 968 intake valve size increased from 37 to 39.0 mm.
  • HP PCS E. 2. n. 4. Add Axle Shaft to Allow FWD the Same Freedom #31592wordingneutralEP, FP, HP front-wheel-drive cars may alter body and suspension to install alternate transmission, transaxle, and axle shaft.
  • HP Weight Adjustment To Fiat X1/9 Spec Lines, H-Production #31653weight -50 lbsfasterHP Fiat X1/9 1500 loses 50 lbs to 1950; 1300 loses 45–47 lbs; Bertone 1500 loses 50–52 lbs.
  • HP 1500 Midget #31665cars addedneutralAustin-Healey Sprite Mk I, II, III, IV and MG Midget classified in HP Prep with 1510–1586 lbs depending on prep level.
  • HP BMW Z3 2.5L Spec Line #31724wordingneutralEP BMW Z3 2.5L allows alternate throttle body from 92-95 325i with Turner adapter; head casting 1738400 permitted with specific blocks.
  • HP Request weight requirement for 1500 MG Midget #31802cars addedneutralAustin-Healey Sprite Mk I–IV and MG Midget classified in HP with 1655 lbs minimum weight.
  • FC Clarify Zetec ECU requirements #31554wordingneutralFC Zetec ECU requirements clarified: Pectel T2 or Performance PE-3 required with specific communications ports and SCCA tune-file/map.
  • 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 addedneutralHP Corolla GTS RWD (84-87) added at 2300 lbs; HP Corolla FX16 FWD (87-88) added at 2260 lbs; old Corolla (84-87) removed.
  • HP 944S2 Restrictor #31396inductionslowerEP Porsche 944S2 89-91 requires 56mm flat plate intake restrictor; comp ratio max 12.0:1, valve lift max 0.500".
  • HP Classing Clarification for 1986 Toyota Corolla FX16 #31527cars addedneutralHP Corolla GTS RWD (84-87) added at 2300 lbs; HP Corolla FX16 FWD (87-88) added at 2260 lbs; old Corolla (84-87) removed.
  • FC Clarify composite anti-intrusion panel language #31426wordingneutralFC composite anti-intrusion panels of non-uniform thickness limited to eight fasteners per side.
  • FC Clarify tire marking requirements #31455wordingneutralFC tire marking rules clarified: competitor responsible for declaring, marking, and logging tires with Tech before qualifying or race.
  • FP E&O; MR2 Track #31120wordingneutralHP Toyota MR-2 1.6L (85-89) track corrected to 15.47 inches front and rear.
  • HP E&O; MR2 Track #31120wordingneutralHP 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.
  • HP 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.
  • HP 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.
  • 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 addedneutralPlymouth 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 addedneutralBMW 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 addedneutralDaimler SP 250 classified in EP at 2165 lbs with 2548 cc OHV 8-cylinder engine.
  • HP Lotus/Caterham 7 America Request #30392wordingunclearEP Lotus/Caterham 7 America carburetor changed from IT fuel injection prep to fuel injection.
  • HP Request to classify ITC Plymouth Arrow #30588cars addedneutralPlymouth Arrow 1598cc four-cylinder classified to HP at 1800 lbs minimum weight.
  • HP Reclassification of the 1984/85 BMW 318i from FP to HP #30661cars addedneutralBMW 318i E30 (84-85) reclassified from FP to HP at 2200–2310 lbs with fuel injection and .425" valve lift limit.
  • HP Reclassify Daimler SP 250 #30721cars addedneutralDaimler SP 250 classified in EP at 2165 lbs with 2548 cc OHV 8-cylinder engine.
  • FP Move Porsche 924 in Level 1 Prep From EP to FP #30135cars addedneutralPorsche 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.
  • HP 924 Brakes- and Thank You. #30614suspension & brakesfasterHP Spec Line Porsche 924 (76-84) brakes change from solid to vented disc.
  • HP 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.
  • HP Correct Induction Error on new HP Mazda 626 Spec Line #30702inductionunclearHP Mazda 626 (84-87) induction changed from dual 32mm sidedraft carbs to carburation or fuel injection.
  • FP Change Classification of 84-87 Mazda 626 from FP to HP #30350cars addedneutral84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lbs weight, 1998cc SOHC, dual 32mm carbs.
  • FP Fiat X1/9 brake rotors #30423suspension & brakesneutralFP Fiat X1/9 brake rotors change to 257 (10.1) x 12 (.407) solid disc.
  • HP Volvo 142 spec line complete. #29479cars addedneutralVolvo 142/142E moves from HP Spec P-1800 Engine to HP Prep with 1989cc OHV four-cylinder, 2450–2573 lbs.
  • HP Request to Classify 93-98 Volkswagen Golf to HP #29790cars addedneutralVolkswagen Golf III/Jetta III 93-98 classified to HP at 2325–2441 lbs with 1984cc SOHC engine.
  • HP Appeal of Request to Move Porsche 924 to HP #30132cars addedneutralPorsche 924 (76-84) newly classified to HP with 2400-2520 lbs weight, fuel injection, 1984cc engine.
  • HP Change Classification of 84-87 Mazda 626 from FP to HP #30350cars addedneutral84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lbs weight, 1998cc SOHC, dual 32mm carbs.
  • HP Fiat X1/9 brake rotors #30423suspension & brakesneutralFP Fiat X1/9 brake rotors change to 257 (10.1) x 12 (.407) solid disc.
  • FP Please Classify Mazda3 in FP #30165cars addedneutralMazda 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.
  • HP Request to Classify 2012-2015 MINI Cooper Coupe in HP #30167cars addedneutralHP Mini Cooper classification expands to include 12-15 Coupe model in existing spec line.
  • HP Request clarification on VW 1.8 Rabbit GTI Spec Line #30368wordingneutralHP Volkswagen Rabbit GTI 1780 (83-84) permits Mk2 VW front spindles, hubs and bearings.
  • FC Request for FC Weight Change #30171weightfasterFC Pinto engine loses 10 lbs to 1190; Pinto aluminum head loses 10 lbs to 1190; Zetec loses 10 lbs to 1210.
  • FP Alternate Front Brake Rotors and Calipers for EP AH 3000 #29893suspension & brakesneutralEP Austin-Healey 3000 Mk. I, II, III now allows TR-6 front calipers and discs as alternate.
  • FP Request VW weight break #29963weight -50 lbsfasterFP 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.
  • HP Alternate Front Brake Rotors and Calipers for EP AH 3000 #29893suspension & brakesneutralEP Austin-Healey 3000 Mk. I, II, III now allows TR-6 front calipers and discs as alternate.
  • 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 #29406wordingneutralEP, 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 addedneutralHonda Civic EX 96-00 classified in FP at 1975 lbs, 1590cc SOHC, 56mm throttle body, valve lift .450" max.
  • FP FAJS Carburetor #29576wordingneutralFP adds FAJS carburetor to permitted Weber and auto-type substitutions in two rule sections.
  • HP 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.
  • HP Correct Wording for Level 1 and Level 2 Induction Systems #29406wordingneutralEP, FP, HP Level 1 and Level 2 induction systems: clarified carburetor and fuel injection rules, jets/needles/rods unrestricted in Level 2.
  • HP Weight Reduction for Datsun Roadster #29409weight -75 lbsfasterEP Datsun SRL 311U Roadster minimum weight reduced to 1925 lbs from 2000 lbs.
  • HP EP TR8 Adjustment #29512weight -100 lbsfasterEP Triumph TR8 78-81 weight reduced from 2600 to 2500 lbs.
  • FC Urgent: SCCA PE3 map unsuitable #29475wordingneutralFC: Pectel T2 and Performance PE-3 ECU maps clarified; SCCA Club or 2013 Pro map required.
  • 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.
  • HP 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.
  • FC Request for weight adjustments to equalize FC competition. #28888weightslowerFC Zetec engine minimum weight increases 20 lbs to 1220 lbs.
  • FP EP BMW Z3 Rule Clarification #28998wordingneutralEP BMW Z3 2.5L iron block casting 1738566-C designation removed, wording clarification only.
  • HP EP BMW Z3 Rule Clarification #28998wordingneutralEP BMW Z3 2.5L iron block casting 1738566-C designation removed, wording clarification only.
  • FP Request to Classify Porsche 911 2.0L #28456cars addedneutralPorsche 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.
  • HP Request to Classify Porsche 911 2.0L #28456cars addedneutralPorsche 911 S 67-68 classified in EP at three weight levels: 1800, 1845, or 1890 lbs.
  • HP Request Dual Carbs for 1.8 VW GTI Mk1 #28922wordingneutral1.8 VW GTI Mk1 dual carb request denied; remains stock fuel injection only.
  • 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 addedneutralFP Volkswagen Scirocco E&O adds four engine variants with weights 1520–1853 lbs and displacements 1471–1780 cc.
  • HP 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 Request to Classify 1990-1994 Mazda Protege #28381cars addedneutral1990-1994 Mazda Protege classified in FP Pre at 2150–2258 lbs with 1839cc DOHC engine, fuel injection.
  • FP Error in Mini Cooper Spec Line #28713wordingneutralHP Mini Cooper model year ranges for convertibles revised: 02-06 now includes 05-08, 07-13 now includes 09-15.
  • HP Request to Classify 1990-1994 Mazda Protege #28381cars addedneutral1990-1994 Mazda Protege classified in FP Pre at 2150–2258 lbs with 1839cc DOHC engine, fuel injection.
  • HP Error in Mini Cooper Spec Line #28713wordingneutralHP 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 #28498wordingneutralEP 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 addedneutral1989-90 Nissan 240-SX SOHC added to FP Level 2 with 2400-2520 lbs weight range.
  • HP Caterham 7 Spec Line #28498wordingneutralEP Caterham 7 Spec Line removes redundant suspension note, clarifies engine prep limits and comp ratio to 10.0:1.
  • FP VW Weight and Valve Size Request #27886wordingneutralFP Volkswagen Jetta, Rabbit, Scirocco 1457-1853cc reclassified with inlet valve 40.0mm, exhaust 33.0mm, weights 1520-1853 lbs.
  • 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 addedneutralPorsche 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.
  • HP Letter #27917 #28085wordingneutralHP Volkswagen Rabbit and Scirocco 1588 remove 32mm choke requirement, clarify carburetor options and weight penalties.
  • HP Request to Classify 2007 - 2013 Mini Cooper Convertible #28111cars addedneutralHP Mini Cooper Convertible (07-13) newly classified; (05-08) convertible spec consolidated into main listing.
  • HP Allow HP Datsun 510 Under Level 2 to Utilize Datsun Z Brakes #28121suspension & brakesneutralHP Datsun 510 Level 2 brakes changed from factory spec to 9.1 disc front, 9.0 drum rear, allowing 240Z/260Z/280Z parts.
  • HP 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.
  • HP Request Ford Fiesta Weight Adjustment #28337weightfasterHP Ford Fiesta 78-80 minimum weight drops 50 lbs to 1725; both asterisk tiers drop 51 lbs.
  • FP Request for Help for Datsun 1200 #27934inductionfasterHP Datsun 1200 carburetor choke size increases from 26mm to 30mm.
  • HP Request for Help for Datsun 1200 #27934inductionfasterHP Datsun 1200 carburetor choke size increases from 26mm to 30mm.
  • FP Request to List Mazda Miata Throttle Body Size #27907wordingneutralFP 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 addedneutralFP 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.
  • HP Update years for the Mazda2, Honda Fit, & Mini #27782wordingneutralHP Mazda2 updates to 11-14, Honda Fit to 15-19, Mini Cooper to 07-13.
  • HP Allow Dry Sump, Limited Prep Porsche 914 #27814wordingneutralHP Porsche 914-4 1.8L now allows 2-stage dry sump if cam-driven and OEM-located.
  • HP Please Allow Alternate Rear Axle Housing for RWD Toyota Corolla #27854wordingneutralHP Toyota Corolla 71-74 permitted to use rear axle housing from 84-87 Corolla.
  • HP Request to List Mazda Miata Throttle Body Size #27907wordingneutralFP and EP Mazda Miata models standardized to 55mm throttle body diameter; brake spec clarified.
  • HP HP VW Rabbit Convertible 1.6L #1922 and 32mm chokes #27917weightfasterHP VW Rabbit Convertible and Scirocco 1.6L lose 50 lbs minimum weight, to 1735.
  • FC Request for Better Zetec Connecting Rods #27710wordingneutralFC Zetec connecting rods now allow Eagle #CRS5483F3D in addition to original Ford.
  • FC Add Alternate Piston #27795wordingneutralFC adds Mahle #930169439 piston as alternate option to existing Ford, Sealed Power, and United Engine choices.
  • FP Request to Correct Track of 1988-91 Honda Civic #27487wordingneutralFP 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 #27661wordingneutralEP, FP, HP cylinder head rules reorganized for clarity; no performance change.
  • HP Request to Correct Track of 1988-91 Honda Civic #27487wordingneutralFP and HP Honda Civic and CRX 1988–91 track specifications corrected to 61.3/61.7 inches.
  • HP Re-organize Prep2 Cylinder Head Rules for Clarity & Consistency #27661wordingneutralEP, FP, HP cylinder head rules reorganized for clarity; no performance change.
  • FP Request bodywork for Austin Healey Bugeye Sprite MK1 #27106wordingneutralFP 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 #27263wordingneutralEP Mazda MX-5 Global Cup classification year changes from 16-18 to 16-19.
  • FP level one susp. component rule #27270wordingneutralProduction suspension rule clarifies spindles, hubs, bushings, bearings, ball joints unrestricted.
  • FP Clarification of Carb Rules - Prep 1 #27300wordingneutralProduction carb rules clarified: carburetor options, fuel injection throttle body dimensions, and intake manifold restrictions reorganised and refined.
  • FP Clarification of Carb Rules - Prep 2 #27301wordingneutralEP, FP, HP carburetors clarified: jets, needles, metering rods, needle valves unrestricted; choke parts removable; permitted optional carburetors listed.
  • HP Request bodywork for Austin Healey Bugeye Sprite MK1 #27106wordingneutralFP and HP Austin-Healey Sprite Mk I and MG Midget variants may replace rear bodywork aft of cockpit with stock-appearing alternate material components.
  • HP Request to classify the GMX5 2019 #27263wordingneutralEP Mazda MX-5 Global Cup classification year changes from 16-18 to 16-19.
  • HP level one susp. component rule #27270wordingneutralProduction suspension rule clarifies spindles, hubs, bushings, bearings, ball joints unrestricted.
  • HP Clarification of Carb Rules - Prep 1 #27300wordingneutralProduction carb rules clarified: carburetor options, fuel injection throttle body dimensions, and intake manifold restrictions reorganised and refined.
  • HP Clarification of Carb Rules - Prep 2 #27301wordingneutralEP, FP, HP carburetors clarified: jets, needles, metering rods, needle valves unrestricted; choke parts removable; permitted optional carburetors listed.
  • FP Request Miata Eligibility - 2003 #27121cars addedneutralEP Mazda MX-5/Miata eligibility years expanded from 1999-2002 to 1999-2005.
  • HP Request Miata Eligibility - 2003 #27121cars addedneutralEP Mazda MX-5/Miata eligibility years expanded from 1999-2002 to 1999-2005.
  • FC E&O Wiseco piston and Crower connecting rod #26659wordingneutralFC Wiseco piston and Crower connecting rod part numbers updated; minimum weight 976 grams.
  • 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 #26476wordingneutralEP open cars may now use aftermarket hardtops if they retain OEM appearance; specific model hardtop allowances removed.
  • HP 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.
  • HP Hardtops #26476wordingneutralEP 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.
  • HP Do Something About the Toyota Yaris In H Production #25834weight +130 lbsslowerHP Toyota Yaris 06-11, 07-12 sedan, 12-18 add 130-136 lbs minimum weight.
  • HP Request to Allow 2011+ Fiesta to Change Bolt Pattern on Wheels #25929wordingneutralHP Ford Fiesta years corrected to 11-16; Mazda hubs D651-33-06 front and D651-26-15XE rear allowed.
  • FC Correct Wiseco piston and connecting rod #25809weightslowerFC Wiseco piston and Crower connecting rod assembly minimum weight increases from 555 to 976 grams.

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 FP" is the class's best as a share of FP'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 FP'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.