BoP Lab / Classes / FE2

FE2 vs GT2 vs SM vs F5 pace at every track

Lap times across years say as much about the weather as the class. % of FE2 is each class's best lap as a share of FE2's on the same day, so the conditions drop out: 100% is level, less is quicker, and a move in it is the class getting faster or slower against the field.

Class · click a class to switch, + to compare alongside (up to 4: remove one to add another)

ASB-SpecEPvsF5 ×FAFCFE2×FFFPFVFXGT1vsGT2 ×GTXHPPP2vsSM ×SMXSRF3STLSTUT1T2T3T4Show 50 inactive classes

Series Runoffs Super Tour Both

Reference class · the yardstick the % column and chart are measured against

Tracks · untick to narrow Auto Club Speedway Barber Motorsports Park Blackhawk Farms Raceway Buttonwillow Raceway Park Circuit of St. Louis (formerly Gateway Motorsports Circuit of the Americas Daytona International Speedway Grattan Raceway Hallett Motor Racing Circuit Homestead-Miami Speedway Indianapolis Motor Speedway Laguna Seca Michelin Raceway Road Atlanta Mid-Ohio Sports Car Course New Jersey Motorsports Park NOLA Motorsports Park Pacific Raceways Pittsburgh International Race Complex Portland International Raceway Pueblo Motorsports Park Road America Sebring International Raceway Sonoma Raceway Summit Point Raceway Thunderhill Raceway Park Virginia International Raceway Watkins Glen International Willow Springs Raceway World Wide Technology Raceway

Quickest here: FE2 1:35.040 Flinn Lazier, Runoffs 2018 qualifying · GT2 1:25.405 Andrew Aquilante, Runoffs 2016 qualifying · SM 1:40.514 Justin Hille, Runoffs 2016 qualifying · F5 1:28.528 Calvin Stewart, Runoffs 2016 qualifying

% of FE2Lap times

FE2GT2SMF5solid race · dashed qualifying · slower is lower

FE2GT2SMF5solid race · dashed qualifying · each class's best lap as a share of FE2's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker

	Event	FE2			GT2					SM					F5
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs FE2	% of FE2	Qual best	Race best	Trap	vs FE2	% of FE2	Qual best	Race best	Trap	vs FE2	% of FE2
	Road America Runoffs 20262026-09-28	2:12.326Franklin Futrelle · fastest of 8 · top 5 within 1.9s-0.149s (-0.11%)	2:11.881Franklin Futrelle · fastest of 8 · top 5 within 1.6s-1.458s (-1.09%)	143.5Steve Whitston-5.5 mph (-3.7%)	2:09.634John Atwell · fastest of 18 · top 5 within 4.3s-2.173s (-1.65%)	2:10.650John Atwell · fastest of 18 · top 5 within 4.1s-2.797s (-2.10%)	163.0Jack Stanford-0.3 mph (-0.2%)	-1.231squal -2.692s	99.1%qual 98.0%	2:42.173Brett Kowalski · fastest of 34 · top 5 within 0.3s-0.938s (-0.58%)	2:42.725Francisco Barroso · fastest of 35 · top 5 within 0.2s-1.705s (-1.04%)	119.6Wyatt Couch+0.3 mph (+0.3%)	+30.844squal +29.847s	123.4%qual 122.6%
16 rule changes (FE2: 1, GT2: 13, SM: 2)8 cars added · 1 weight · 4 wording · 3 other · SM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361. · GT2 Panoz Esperante GTS spec simplified to standard GT2 rules unless noted; detailed suspension, brake, aero specs removed. · TA2 shock absorbers rise to $1005, rear calipers to $585, brake pads to $330 per axle; wheels drop to $165. · GT2 Porsche 991.1 GT3 Cup now permits modifications from Grand Am, IMSA Cup, World Challenge rules; factory Lexan windows and ABS allowed. · GT2-ST Corvette C7 L76 minimum weight drops 100 lbs to 3000, restrictor rises to 83 mm FPR. · GT2 Porsche 997.2 GT3 Cup removes permission for Lexan front windows and clarifies ABS allowance status. · SM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. · Ginetta G56 GT4 (V8) added to GT2 with GM LS V8, 6.2L, 72mm restrictor, 3300 lbs. · GT3U class removed from GCR; GT3U cars now compete in STU. · GT2 Audi R8 GT4 removes requirement to carry GT4 rules at events, directs to GT2-ST header note. · GT2 Porsche 911 SC gains 4.0L air-cooled engine option at 2275 or 2350 lbs depending on valve count. · M3 E92 classified in GT2 with 3999cc V8, 35mm restrictor, 3300 lb minimum weight. · GT2 adds Cadillac CTS, Chevrolet Impala/Malibu/Monte Carlo/SS, Dodge Intrepid, Ford Fusion/Taurus, Lincoln MKS, Pontiac G8/GTO/Grand Prix, Toyota Camry, and Gen late Model Stock Car bodies Camaro/Mustang/Camry. · GT2 Mazda BP 1839cc DOHC classified with 2250 lbs minimum weight, 46mm restrictor, EFR6258 or EFR7163 turbo allowed. · FE and FE2 Enterprise bubble tail part WM138014 now allowed; FE2 must use this configuration only.showhide 2026-07-01 SM Rear Toe Link #40271wordingwordingSM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361. 2026-05-01 GT2 Panoz Esperante GTS Letter ID Number: #38494 - Additional Info #38584wordingunclearGT2 Panoz Esperante GTS spec simplified to standard GT2 rules unless noted; detailed suspension, brake, aero specs removed. 2026-05-01 GT2 Appendix L Update #39923otherotherTA2 shock absorbers rise to $1005, rear calipers to $585, brake pads to $330 per axle; wheels drop to $165. 2026-05-01 GT2 GT2 Porsche 997.2 GT3 Cup EDIT #40125otheraddedGT2 Porsche 991.1 GT3 Cup now permits modifications from Grand Am, IMSA Cup, World Challenge rules; factory Lexan windows and ABS allowed. 2026-04-01 GT2 Corvette C7 (14-19) L76 Specline Errors/Missing Changes #39838weight -100 lbsfaster · weightGT2-ST Corvette C7 L76 minimum weight drops 100 lbs to 3000, restrictor rises to 83 mm FPR. 2026-04-01 GT2 GT2 Porsche 997.2 GT3 Cup #39936wordingwordingGT2 Porsche 997.2 GT3 Cup removes permission for Lexan front windows and clarifies ABS allowance status. 2026-04-01 SM Part Number Change Request #39914otherunclearSM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. 2026-03-01 GT2 Classification Request - Ginetta G56 GT4 (V8) #39625cars addedaddedGinetta G56 GT4 (V8) added to GT2 with GM LS V8, 6.2L, 72mm restrictor, 3300 lbs. 2026-03-01 GT2 Remove GT3U from GCR as it is now in STU #39862cars addedremoved · cars addedGT3U class removed from GCR; GT3U cars now compete in STU. 2026-03-01 GT2 Audi R8 GT4 remove spec line notes #39864wordingwordingGT2 Audi R8 GT4 removes requirement to carry GT4 rules at events, directs to GT2-ST header note. 2026-02-01 GT2 Allow Larger Air Cooled Engines in Porsche 911 GT2 #39249cars addedaddedGT2 Porsche 911 SC gains 4.0L air-cooled engine option at 2275 or 2350 lbs depending on valve count. 2026-02-01 GT2 Classify T1 BMW in GT2 #39408cars addedaddedM3 E92 classified in GT2 with 3999cc V8, 35mm restrictor, 3300 lb minimum weight. 2026-01-01 GT2 Additional Body Options to Replace Older Stock Car Bodies #39086cars addedaddedGT2 adds Cadillac CTS, Chevrolet Impala/Malibu/Monte Carlo/SS, Dodge Intrepid, Ford Fusion/Taurus, Lincoln MKS, Pontiac G8/GTO/Grand Prix, Toyota Camry, and Gen late Model Stock Car bodies Camaro/Mustang/Camry. 2026-01-01 GT2 GT3 Turbo to GT2? #39365cars addedaddedGT2 Mazda BP 1839cc DOHC classified with 2250 lbs minimum weight, 46mm restrictor, EFR6258 or EFR7163 turbo allowed. 2026-01-01 GT2 Tech Bulletins for GT2 and GT2-ST #39537cars added -100 lbs 2025-10-01 FE2 FE & FE2 Bubble Tail #38978cars addedaddedFE and FE2 Enterprise bubble tail part WM138014 now allowed; FE2 must use this configuration only.
	Road America Runoffs 20252025-09-29	2:12.475Franklin Futrelle · fastest of 11 · top 5 within 1.4s+0.969s (+0.74%)	2:13.339Franklin Futrelle · fastest of 10 · top 5 within 0.6s+0.591s (+0.45%)	149.0Steve Whitston+3.7 mph (+2.6%)	2:11.807Brad McAllister · fastest of 16 · top 5 within 3.4s-0.053s (-0.04%)	2:13.447John Atwell · fastest of 13 · top 5 within 3.6s+0.136s (+0.10%)	163.3Charlie Peter-1.0 mph (-0.6%)	+0.108squal -0.668s	100.1%qual 99.5%	2:43.111Bobby Gossett · fastest of 32 · top 5 within 0.3s+2.005s (+1.24%)	2:44.430Kyle Greenhill · fastest of 28 · top 5 within 0.3s+2.944s (+1.82%)	119.3Francisco Barroso-0.6 mph (-0.5%)	+31.091squal +30.636s	123.3%qual 123.1%
12 rule changes (FE2: 1, GT2: 7, SM: 4)2 aero · 1 cars added · 1 induction · 1 weight · 5 wording · 2 other · GT2 Porsche 911, 963, 994 may use 993 3.8 RSR rear deck lid or faithful aftermarket reproductions. · 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 fines, level 2 and 4 may carry $500 fines. · SM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only. · FE2 allows pre-approved driver safety and comfort seat and control modifications for drivers with disabilities, per logbook. · GT2 Pontiac Fiero drivetrain changed to RWD and hood bulge permitted for front engine relocation. · TA2 OEM wing height rule exemption removed; STO permits factory aero but bans it with aftermarket wings. · GT2 STO aftermarket ABS weight penalty reduced from 100 lbs to 50 lbs. · GT2 Panoz Esperante GTS adds 2013-2016 Ford EcoBoost Twin Turbo V-6, 3496 cc, 2600 lbs, twin turbo induction. · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit. · GT2 Sunbeam Tiger gains Holly 650 cfm carburetors PN #80541-1 and PN #80541-2 as alternate options. · SMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation.showhide 2025-08-01 GT2 Rear Deck Lid for Older Air-Cooled Porsche #38506aeroadded · aeroGT2 Porsche 911, 963, 994 may use 993 3.8 RSR rear deck lid or faithful aftermarket reproductions. 2025-06-01 SM SMX Data Submission - Penalties #38248otheraddedSMX drivers must submit data acquisition files on time or face suspension and $250 fine. 2025-06-01 SM Committee) SMX Penaly Clarification updated language #38337wordingwordingSMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines. 2025-05-01 SM Clarify Tire Marking Regs #38005wordingwordingSM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only. 2025-04-01 FE2 Driver Safety & Comfort #37965otheraddedFE2 allows pre-approved driver safety and comfort seat and control modifications for drivers with disabilities, per logbook. 2025-03-01 GT2 Hood Bulge allowed #37000wordingwordingGT2 Pontiac Fiero drivetrain changed to RWD and hood bulge permitted for front engine relocation. 2025-03-01 GT2 OEM Wing Adjustment #37590aeroaeroTA2 OEM wing height rule exemption removed; STO permits factory aero but bans it with aftermarket wings. 2025-02-01 GT2 GT2/ST - Remove Aftermarket/Racing ABS penalty #36538weightfaster · weightGT2 STO aftermarket ABS weight penalty reduced from 100 lbs to 50 lbs. 2025-01-01 GT2 Panoz Esperante GTS BOP #36686cars addedaddedGT2 Panoz Esperante GTS adds 2013-2016 Ford EcoBoost Twin Turbo V-6, 3496 cc, 2600 lbs, twin turbo induction. 2025-01-01 GT2 Correct language regarding OEM Areo Devices #37137wordingwordingTA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit. 2025-01-01 GT2 GT2 Sunbeam Tiger Alternate Carburetor #37198inductionadded · inductionGT2 Sunbeam Tiger gains Holly 650 cfm carburetors PN #80541-1 and PN #80541-2 as alternate options. 2024-12-01 SM E&O SMX Regs 9.1.7.1.D.5.u-.w #37070wordingwordingSMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation.
	Road America Runoffs 20242024-10-01	2:11.506Porter Aiken · fastest of 18 · top 5 within 0.5s-1.300s (-0.98%)	2:12.748Porter Aiken · fastest of 17 · top 5 within 2.0s-0.523s (-0.39%)	145.3Porter Aiken+1.9 mph (+1.3%)	2:11.860Charlie Peter · fastest of 23 · top 5 within 1.1s-0.438s (-0.33%)	2:13.311John Atwell · fastest of 23 · top 5 within 0.9s-0.968s (-0.72%)	164.3Jonathan Start+2.1 mph (+1.3%)	+0.563squal +0.354s	100.4%qual 100.3%	2:41.106Ethan Goulart · fastest of 49 · top 5 within 0.5s-1.103s (-0.68%)	2:41.486Brett Kowalski · fastest of 43 · top 5 within 0.3s-2.262s (-1.38%)	119.9Alex Bertagnoli-1.4 mph (-1.2%)	+28.738squal +29.600s	121.6%qual 122.5%
17 rule changes (GT2: 13, SM: 4)5 engine · 3 cars added · 3 weight · 1 aero · 3 wording · 2 other · SMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification. · SM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01. · SMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only. · SM and SMX now allow an alternate shifter bushing at the bottom of the shift lever. · GT2-ST: aftermarket replacement differential housings permitted if exact equivalent. · GT4 cars now permitted in GT2-ST with factory power stick or Pro Series restrictor, 100-pound weight penalty for slicks. · GT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR. · GT2-ST Spec Corvette (14-19) LS2 restrictor increases from 78mm to 80mm flat plate. · Chevrolet Corvette C8 (2020–) classified in GT2-ST: 6162 cc, 3300 lbs minimum, 71 mm restrictor, flat plate. · Mitjet ST 2015 added to GT2, must run per VTS specs with FIA form CdM008. · GT1-GTX rear blade spoiler: angle 50–75°, max 59.0 wide by 5.0 high inches; total area limit removed. · GT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment. · GT2 Chevrolet Corvette 7011 OEM 7-liter minimum weight reduces to 3125 lbs, down 150 lbs. · GT2 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E. · GT2 Dodge Viper Gen 3 hybrid kit restrictor reduced from 50mm to 45mm flat plates in 8300 class. · GTL spec lines moved contiguous with GT2 and GT3; GTA category and specs renumbered behind GTL; P2 engine tables reorganised with restrictor and weight specifications clarified. · GT2-ST Dodge Viper including Comp Coupe, ACR/ACR-X adds VRL front fascia, 100 lbs weight reduction.showhide 2024-09-01 SM SMX Camera Rule Correction #36496wordingwordingSMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification. 2024-09-01 SM Committee) AIM ECU Protocol #36556engineadded · engineSM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01. 2024-09-01 SM Committee) OE versus OEM Definitons #36608wordingwordingSMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only. 2024-09-01 SM Committee) Shifter Bushing #36611otheraddedSM and SMX now allow an alternate shifter bushing at the bottom of the shift lever. 2024-07-01 GT2 GT2-ST Rule Clarification #36093otheraddedGT2-ST: aftermarket replacement differential housings permitted if exact equivalent. 2024-07-01 GT2 GT4 cars may run in GT2-ST #36235cars addedaddedGT4 cars now permitted in GT2-ST with factory power stick or Pro Series restrictor, 100-pound weight penalty for slicks. 2024-05-01 GT2 Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslower · weightGT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR. 2024-05-01 GT2 Request to Eliminate the FPR from the Corvette (-2013) with LS2 #35878enginefaster · engineGT2-ST Spec Corvette (14-19) LS2 restrictor increases from 78mm to 80mm flat plate. 2024-03-01 GT2 Classify Corvette C8 (2020- ) into GT2/ST #33759cars addedaddedChevrolet Corvette C8 (2020–) classified in GT2-ST: 6162 cc, 3300 lbs minimum, 71 mm restrictor, flat plate. 2024-03-01 GT2 Requesting classification for a 2015 Mitjet ST in GT2 #35408cars addedaddedMitjet ST 2015 added to GT2, must run per VTS specs with FIA form CdM008. 2024-02-01 GT2 Rear Blade Spoiler Clarification #35261aeroaeroGT1-GTX rear blade spoiler: angle 50–75°, max 59.0 wide by 5.0 high inches; total area limit removed. 2024-02-01 GT2 GT Direct Injection allowance and rules #35437engineadded · engineGT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment. 2024-02-01 GT2 REDUCE C6 CORVETTE WEIGHT WITH OEM 7 LITER ENGINE REDUCE BY 150LB #35385weight -150 lbsfaster · weightGT2 Chevrolet Corvette 7011 OEM 7-liter minimum weight reduces to 3125 lbs, down 150 lbs. 2024-02-01 GT2 GT2/3 remove Direction Injection not allowed in Spec line notes #35439engineadded · engineGT2 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E. 2024-01-01 GT2 Dodge Viper Gen 3 hybrid Kit Update Request #35200engineslower · engineGT2 Dodge Viper Gen 3 hybrid kit restrictor reduced from 50mm to 45mm flat plates in 8300 class. 2023-12-01 GT2 Errors in GTCS Headings and Use of the Terms Category and ClassChange existing GTL and GTA Rules #34453wordingwordingGTL spec lines moved contiguous with GT2 and GT3; GTA category and specs renumbered behind GTL; P2 engine tables reorganised with restrictor and weight specifications clarified. 2023-10-01 GT2 Late E & O #34966weightfaster · weightGT2-ST Dodge Viper including Comp Coupe, ACR/ACR-X adds VRL front fascia, 100 lbs weight reduction.
	Virginia International Raceway Runoffs 20232023-09-23	1:50.665Charles Russell Turner · fastest of 26 · top 5 within 2.3s-0.188s (-0.17%)	1:51.098Franklin Futrelle · fastest of 19 · top 5 within 1.4s-20.947s (-15.86%)	141.3Franklin Futrelle-0.6 mph (-0.4%)	1:52.004Barry Boes · fastest of 15 · top 5 within 1.6s+0.918s (+0.83%)	1:52.865Jared Odrick · fastest of 15 · top 5 within 1.0s-0.183s (-0.16%)	164.0Tom Patton-0.2 mph (-0.1%)	+1.767squal +1.339s	101.6%qual 101.2%	2:14.986Danny Steyn · fastest of 52 · top 5 within 0.1s+0.322s (+0.24%)	2:16.229Julian DaCosta · fastest of 46 · top 5 within 0.3s-2.878s (-2.07%)	120.3Jim Drago+1.1 mph (+0.9%)	+25.131squal +24.321s	122.6%qual 122.0%
20 rule changes (GT2: 19, SM: 1)7 engine · 4 cars added · 2 induction · 2 weight · 1 aero · 1 tyres & wheels · 1 wording · 2 other · GT2 Mazda 20B rotary minimum weight reduced to 2280 lbs, with 100-lb penalty for Grand Am transaxle and independent rear suspension. · GT2 BMW E46 M3, E36, Z3, 5000cc V8: 3.4L at 2575 lbs, 4.0L at 2900 lbs, 4.5L at 2950 lbs, 5.0L at 3000 lbs; S54 97mm stroke permitted at 2800 lbs. · GT2 Corvette C7 restrictor increases from 73mm to 77mm flat plate. · GT2 adds 2009-2012 Porsche Cayman S, 3.4L, RWD, no PDK transmission. · Fields Cardinal V8 added to GT1 with Ford V8 engine, 4.9L, 2100 lbs, fuel injection. · GT2 Ginetta G56 GTA may use Factory installed ProMap ECU Map. · GT2 Mazda 13B Street Port turbo changes from EFR 76/70 to BW7670 or Garrett G30-660 with 46mm TIR at 2280 lbs. · GT2 Porsche SOHC 2478/2681/2992 turbos: EFR 76/70 compressor 42mm to 44mm, SIR to TIR designation. · GT2-ST Chevrolet Corvette 14-19 restrictor increases from 70 to 73 mm. · GT2 and GTL add Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines as permitted options. · GT2 Mazda 13B turbocharger part number changed from EFR 70/76 to 76/70, compressor 42mm to 46mm. · GT2-ST BMW E36/46 spec line adds MA Shaw carbon/composite door and body kit options to notes. · GT3 normally aspirated cars may now use chokes instead of SIRs, same size as listed SIR, one per carburetor barrel. · GT3 2.0L 4-valve non-turbo engines may run unrestricted at 2060 lbs minimum weight. · GT2 Porsche 991.1 TBR 70–72mm, 991.2 weight 3100–3000lbs TBR 65–67mm, all 991/997 models ABS now free; GT2-ST Corvette and others flat plate 75–78mm, 74–77mm, 71–74mm, 68–71mm, 65–68mm per engine; Viper weight 3275–3125lbs all displacement… · SM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. · GT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870. · GT2 Ginetta G56 GTA may now use optional 18" x 9" and 18" x 10" wheels. · GT2/ST BMW E36/E46 Z3 5000cc V8 now permits MAShaw body kit: wide body, M3 front bumper with splitter, fenders, rockers, flairs, rear bumper. · GT2 Chevrolet Corvette L76 5967 restrictor increases from 73 mm to 74 mm.showhide 2023-09-01 GT2 GT2 Mazda 20B 3 rotor ENO #34765weight -220 lbsfaster · weightGT2 Mazda 20B rotary minimum weight reduced to 2280 lbs, with 100-lb penalty for Grand Am transaxle and independent rear suspension. 2023-07-01 GT2 appendix letter #33635 #34206cars addedaddedGT2 BMW E46 M3, E36, Z3, 5000cc V8: 3.4L at 2575 lbs, 4.0L at 2900 lbs, 4.5L at 2950 lbs, 5.0L at 3000 lbs; S54 97mm stroke permitted at 2800 lbs. 2023-07-01 GT2 Remove Weight and Restrictor Penalty for Corvette C7 Body #34342enginefaster · engineGT2 Corvette C7 restrictor increases from 73mm to 77mm flat plate. 2023-05-01 GT2 Request to class 2011 Porsche Cayman S #33771cars addedaddedGT2 adds 2009-2012 Porsche Cayman S, 3.4L, RWD, no PDK transmission. 2023-05-01 GT2 Please classify Fields Cardinal V8 #33784cars addedaddedFields Cardinal V8 added to GT1 with Ford V8 engine, 4.9L, 2100 lbs, fuel injection. 2023-04-01 GT2 Adding Ginetta G56 GTA Factory ProTune for GT2 Class #33825engineadded · engineGT2 Ginetta G56 GTA may use Factory installed ProMap ECU Map. 2023-02-01 GT2 GT2 Mazda 13B Turbo #33729engineengineGT2 Mazda 13B Street Port turbo changes from EFR 76/70 to BW7670 or Garrett G30-660 with 46mm TIR at 2280 lbs. 2023-01-01 GT2 Request Permission to Use a Substitute Turbo #33337engineengineGT2 Porsche SOHC 2478/2681/2992 turbos: EFR 76/70 compressor 42mm to 44mm, SIR to TIR designation. 2023-01-01 GT2 Request to Reduce Restriction on C7 GT2 Corvette #33342enginefaster · engineGT2-ST Chevrolet Corvette 14-19 restrictor increases from 70 to 73 mm. 2023-01-01 GT2 Toyota 4A-F and 4A-FE 1.6L DOHC 16V Engine Request #33415cars addedaddedGT2 and GTL add Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines as permitted options. 2023-01-01 GT2 GT2 Mazda 13b turbocharger part # update #33437enginefaster · engineGT2 Mazda 13B turbocharger part number changed from EFR 70/76 to 76/70, compressor 42mm to 46mm. 2023-01-01 GT2 GT2-ST BMW E36/46 spec line remove #33610otheraddedGT2-ST BMW E36/46 spec line adds MA Shaw carbon/composite door and body kit options to notes. 2023-01-01 GT2 GT3 Choke option effective 1-01-2023 #33669inductionadded · inductionGT3 normally aspirated cars may now use chokes instead of SIRs, same size as listed SIR, one per carburetor barrel. 2023-01-01 GT2 GT3 2.0L choke/weight option #33670otheraddedGT3 2.0L 4-valve non-turbo engines may run unrestricted at 2060 lbs minimum weight. 2023-01-01 GT2 BOP adjustment for GT2 & GT2-ST #33681inductionfaster · inductionGT2 Porsche 991.1 TBR 70–72mm, 991.2 weight 3100–3000lbs TBR 65–67mm, all 991/997 models ABS now free; GT2-ST Corvette and others flat plate 75–78mm, 74–77mm, 71–74mm, 68–71mm, 65–68mm per engine; Viper weight 3275–3125lbs all displacement… 2023-01-01 SM BOP for NB1 and NB2 #32309weightslower · weightSM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. 2022-12-01 GT2 GT2 (TA2)/GTA Part Number Update #33315wordingwordingGT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870. 2022-12-01 GT2 Ginetta G56 GTA - Optional Wheels #33357tyres & wheelsadded · tyres & wheelsGT2 Ginetta G56 GTA may now use optional 18" x 9" and 18" x 10" wheels. 2022-11-01 GT2 Allow the MAShaw Body Kit on the GT2/ST Spec Line for BMW E36/E46 #32447aeroadded · aeroGT2/ST BMW E36/E46 Z3 5000cc V8 now permits MAShaw body kit: wide body, M3 front bumper with splitter, fenders, rockers, flairs, rear bumper. 2022-10-01 GT2 Request for C5/C6 Corvette Restrictor Size Review #32982enginefaster · engineGT2 Chevrolet Corvette L76 5967 restrictor increases from 73 mm to 74 mm.
	Virginia International Raceway Runoffs 20222022-09-24	1:50.853Charles Russell Turner · fastest of 25 · top 5 within 1.1s-0.209s (-0.19%)	2:12.045Jason Conzo · fastest of 22 · top 5 within 1.8s+19.891s (+17.74%)	141.9Eric Cruz-0.6 mph (-0.5%)	1:51.086Andrew Aquilante · fastest of 23 · top 5 within 1.1s+0.904s (+0.82%)	1:53.048Daniel Bender · fastest of 17 · top 5 within 3.1s+0.573s (+0.51%)	164.2Scotty B White+1.4 mph (+0.9%)	-18.997squal +0.233s	85.6%qual 100.2%	2:14.664Danny Steyn · fastest of 60 · top 5 within 0.2s+0.112s (+0.08%)	2:19.107Travis Wiley · fastest of 58 · top 5 within 0.9s+2.648s (+1.94%)	119.2Jonathan Neudorf-0.6 mph (-0.5%)	+7.062squal +23.811s	105.3%qual 121.5%	1:57.689James Weida · fastest of 11 · top 5 within 3.9s+0.328s (+0.28%)	2:21.862Sven de Vries · fastest of 10 · top 5 within 14.3s+24.290s (+20.66%)	142.9Calvin Stewart+0.1 mph (+0.1%)	+9.817squal +6.836s	107.4%qual 106.2%
21 rule changes (GT2: 14, SM: 1, F5: 6)6 cars added · 5 engine · 6 wording · 4 other · F500 Rotax 493 and 593 intake boots: removed Moto Tassinari V3124-873B-2 from 493/593 non-HO allowance, added Moto Tassinari V3120-794A-2 option for non-HO. · GT1, GT2, GT3, GTL, GTX tail lights may now be original style or custom panel graphic with functioning red LED brake lamps. · Ginetta GTA G56 added to GT2 as spec car, 2600 lbs, 3.7L Ford V6 sealed, 6-speed Quaife sequential. · F500 Rotax engines now permit Ingi Tech Sparker ignition DCP-CDI-P2 as alternate ECU. · GT2 adds approved carbon roof suppliers and part numbers for BMW E36 and E46 models to Notes. · GT2 BMW E46 M3, E36, Z3, and 5000cc V8 may use 95mm S54 crankshaft at +150 lbs. · Audi R8 GT4 added to GT2 at 5.2L, 3000 lbs minimum weight, factory restrictor. · F500 clarifies stepped diameter exhaust headers prohibited except at cylinder head flange area. · F500 Rotax 593 intake boot options clarified; oil injection pump removal now permitted. · GT2 shock absorber attachment points clarified as movable; wording correction only. · GT2 Porsche 104.0 x 88.0 SOHC minimum weight increases to 2090 lbs; EFR 76/70 turbo allowances added for three Porsche engines at specific weights. · SM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation. · F500 Majors and Runoffs cars must install AIM part #X47KPFSOLO2R0 data box mount for Solo or Solo 2. · Ginetta G40 added to GT2 with Mazda MZR/L5-VE engine, 2488cc or 2399cc, 1950 lbs base weight. · Toyota Supra GT4 added to GT2-ST with 3000cc displacement, 3000 lb minimum weight, factory restrictor. · GT2 Porsche 944/924 may use ERC 76/70 Turbo instead of Jayco super 50. · GT2-ST Porsche Cayman 05-15 throttle body restrictor increased from 70mm to 75mm. · F5 cars must install AIM part #X47KPFSOLO2R0 data box mount for Majors and Runoffs. · GT2 Porsche Cayman 05-15 4.0L and 4.2L swap flat plate restrictor for throttle body restrictor at 2700 lbs. · GT2 Mazda 13B street port gains EFR 70/76 turbocharger with 42mm inlet restrictor at 2280 lbs minimum. · GT3 Volkswagen Fun Cup Beetle EVO3 classified, sealed SOHC 1984cc engine, 2060 lbs minimum weight.showhide 2022-09-01 F5 Intake Boots Correction #33028wordingwordingF500 Rotax 493 and 593 intake boots: removed Moto Tassinari V3124-873B-2 from 493/593 non-HO allowance, added Moto Tassinari V3120-794A-2 option for non-HO. 2022-09-01 GT2 Tail lights on all GT category race cars. #32799wordingwordingGT1, GT2, GT3, GTL, GTX tail lights may now be original style or custom panel graphic with functioning red LED brake lamps. 2022-09-01 GT2 Addendum to letter #32514 Ginetta GTA G56 #33076cars addedaddedGinetta GTA G56 added to GT2 as spec car, 2600 lbs, 3.7L Ford V6 sealed, 6-speed Quaife sequential. 2022-08-01 F5 Ensure availability of ECU for Rotax engines #32695engineadded · engineF500 Rotax engines now permit Ingi Tech Sparker ignition DCP-CDI-P2 as alternate ECU. 2022-08-01 GT2 Information requested for carbon roofs on BMW E36/E46 cars in GT2 #32682cars addedaddedGT2 adds approved carbon roof suppliers and part numbers for BMW E36 and E46 models to Notes. 2022-08-01 GT2 Request to Allow the 95mm S54 BMW Crankshaft in GT2-ST #32698engineadded · engineGT2 BMW E46 M3, E36, Z3, and 5000cc V8 may use 95mm S54 crankshaft at +150 lbs. 2022-08-01 GT2 Request to classify Audi R8 FIA GT4 to GT2 #32805cars addedaddedAudi R8 GT4 added to GT2 at 5.2L, 3000 lbs minimum weight, factory restrictor. 2022-07-01 F5 Clarify stepped exhaust header references #32743wordingwordingF500 clarifies stepped diameter exhaust headers prohibited except at cylinder head flange area. 2022-06-01 F5 593 carb boot availability and oil pump clarification #32527wordingwordingF500 Rotax 593 intake boot options clarified; oil injection pump removal now permitted. 2022-05-01 GT2 Typo in rules for shocks #32308wordingwordingGT2 shock absorber attachment points clarified as movable; wording correction only. 2022-05-01 GT2 additional response to letters #31898 & 32083 #32424engine +140 lbsslower · engineGT2 Porsche 104.0 x 88.0 SOHC minimum weight increases to 2090 lbs; EFR 76/70 turbo allowances added for three Porsche engines at specific weights. 2022-04-01 SM Update GCR Section 9.1.7.3.A.1. #32217wordingwordingSM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation. 2022-03-01 F5 E&O class name #32194otheraddedF500 Majors and Runoffs cars must install AIM part #X47KPFSOLO2R0 data box mount for Solo or Solo 2. 2022-03-01 GT2 Request to Classify Ginetta G40 in GT2 #31597cars addedaddedGinetta G40 added to GT2 with Mazda MZR/L5-VE engine, 2488cc or 2399cc, 1950 lbs base weight. 2022-03-01 GT2 2021 Supra GR GT4 #31737cars addedaddedToyota Supra GT4 added to GT2-ST with 3000cc displacement, 3000 lb minimum weight, factory restrictor. 2022-03-01 GT2 Proposed Technical Bulletin #31900otherunclearGT2 Porsche 944/924 may use ERC 76/70 Turbo instead of Jayco super 50. 2022-02-01 GT2 GT2/ST Porsche Cayman #31451 correct TBR size error #31991enginefaster · engineGT2-ST Porsche Cayman 05-15 throttle body restrictor increased from 70mm to 75mm. 2022-01-01 F5 Data Box Mounting Plate #31638otheraddedF5 cars must install AIM part #X47KPFSOLO2R0 data box mount for Majors and Runoffs. 2022-01-01 GT2 Restrictor Clarification for 2015 Cayman #31451otherunclearGT2 Porsche Cayman 05-15 4.0L and 4.2L swap flat plate restrictor for throttle body restrictor at 2700 lbs. 2021-10-01 GT2 Turbo Request for 13B Engine #30656engineadded · engineGT2 Mazda 13B street port gains EFR 70/76 turbocharger with 42mm inlet restrictor at 2280 lbs minimum. 2021-10-01 GT2 Request car classification #31032cars addedaddedGT3 Volkswagen Fun Cup Beetle EVO3 classified, sealed SOHC 1984cc engine, 2060 lbs minimum weight.
	Indianapolis Motor Speedway Runoffs 20212021-09-25	1:36.395Max Grau · fastest of 28 · top 5 within 0.7s	1:36.655Max Grau · fastest of 28 · top 5 within 0.7s	146.2Gray Fowler	1:39.665Andrew Aquilante · fastest of 22 · top 5 within 1.8s-0.254s (-0.25%)	2:03.513Tim Kezman · fastest of 18 · top 5 within 9.6s+22.537s (+22.32%)	163.7Jonathan Start	+26.858squal +3.270s	127.8%qual 103.4%	1:57.695Brian Henderson · fastest of 90 · top 5 within 0.5s-0.611s (-0.52%)	1:58.837Brian Henderson · fastest of 88 · top 5 within 0.3s-0.263s (-0.22%)	119.8Kyle Greenhill	+22.182squal +21.300s	122.9%qual 122.1%	1:42.619Ryan Mayfield · fastest of 22 · top 5 within 1.6s-0.517s (-0.50%)	1:43.140Sven de Vries · fastest of 20 · top 5 within 1.7s+0.280s (+0.27%)	144.4James Weida	+6.485squal +6.224s	106.7%qual 106.5%
20 rule changes (GT2: 16, SM: 1, F5: 3)5 cars added · 5 weight · 2 engine · 1 aero · 6 wording · 1 other · GT2 Dodge Viper ACR/ACR-X8300 front fascia loses 100 lbs, to 3175 VRL. · F5 clarifies mechanical shifting only; throttle-cut and flat-shifter devices permitted if driver retains full control. · F5 single-seat open-wheel cars: rigid suspension becomes limited suspension in class definition. · GT2 adds 04-06 World Challenge Pontiac GTO, 6062 cc, 3000 lbs minimum, World Challenge rules. · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two locations and 6010 to 6014X in TA2 Appendix. · Grullon GT 2.0L Acura K20 moved from GTX to GT2-ST class at 2350 lbs unrestricted. · GT2-ST Porsche Cayman restrictor increases from 65mm to 75mm flat plate at 2700 lbs. · GT2 Dodge Viper VRL Spec minimum weight reduced 100 lbs to 3275. · TA2 cars may run prior generation rules or current Trans Am rules at 2930 lbs minimum weight with free tire make and size. · F500 Rotax 593 HO engine now permitted; 875 lbs minimum weight, MA0242SP1020A or MA0242SP1063A restrictor, specific intake boots and piston required. · GT2 Sunbeam SBF engine firing order 1,3,7,2,6,5,4,8 now available for Boss 302 variants. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. · GT2-ST Corvette (-2019) LS2 and L76 5967 gain 100 lbs minimum weight to 3100; 6162 and 7011 variants gain 50–100 lbs; L76 restrictor opens 70 to 73 mm. · GT2 rear engine opening position requirement removed. · GT2 Ford Mustang/Thunderbird Boss 302 firing order changes from unrestricted to optional later SBF 302 order 1,3,7,2,6,5,4,8. · GT2 allows ABS braking systems if shown on the individual Spec Line. · GT2 Corvette C6 and C7 spec lines split for clarification; C7 LS2, L76, LS3, LT1, LS7 weights raised 100–150 lbs effective 3/1/2021. · GT2 Ford Mustang/Thunderbird Boss 302 firing order becomes unrestricted. · GT2 BMW E46 M3 and E36, Z3, and 5000cc V8 minimum weight reduced to 2500 lbs. · GT2 Chrysler/Dodge/Plymouth DOHC 2429cc engine classified, 1950 lbs minimum weight.showhide 2021-09-01 GT2 Correct letter 30565 GT2/ST #31088weightfaster · weightGT2 Dodge Viper ACR/ACR-X8300 front fascia loses 100 lbs, to 3175 VRL. 2021-08-01 F5 Clarify allowable assisted shifting systems #30871wordingwordingF5 clarifies mechanical shifting only; throttle-cut and flat-shifter devices permitted if driver retains full control. 2021-08-01 F5 Request to correct terminology #30976wordingwordingF5 single-seat open-wheel cars: rigid suspension becomes limited suspension in class definition. 2021-08-01 GT2 Request the 04-06 Pontiac GTO WC Car Be Added to the GT2/ST Chart #30339cars addedaddedGT2 adds 04-06 World Challenge Pontiac GTO, 6062 cc, 3000 lbs minimum, World Challenge rules. 2021-08-01 GT2 Request to Update GTA Obsolete Part Numbers #30615wordingwordingGTA part numbers updated: 0-80541-1 to 0-80541-2 in two locations and 6010 to 6014X in TA2 Appendix. 2021-08-01 GT2 GTX class correction to GT2/ST #30973cars addedaddedGrullon GT 2.0L Acura K20 moved from GTX to GT2-ST class at 2350 lbs unrestricted. 2021-07-01 GT2 Porsche Cayman Engine Modification and Engine Request #30472enginefaster · engineGT2-ST Porsche Cayman restrictor increases from 65mm to 75mm flat plate at 2700 lbs. 2021-07-01 GT2 Request weight clarification Viper CC #30565weightfaster · weightGT2 Dodge Viper VRL Spec minimum weight reduced 100 lbs to 3275. 2021-07-01 GT2 Variance, 2021 TA2 Rules vs GCR Appendix L #30641cars addedaddedTA2 cars may run prior generation rules or current Trans Am rules at 2930 lbs minimum weight with free tire make and size. 2021-06-01 F5 Request to Allow Rotax 593 HO Engine #30712cars addedaddedF500 Rotax 593 HO engine now permitted; 875 lbs minimum weight, MA0242SP1020A or MA0242SP1063A restrictor, specific intake boots and piston required. 2021-04-01 GT2 GT2 tiger firing order #30421wordingwordingGT2 Sunbeam SBF engine firing order 1,3,7,2,6,5,4,8 now available for Boss 302 variants. 2021-04-01 SM Updates - Obsolete Parts & BOP Parts #30438wordingaddedSM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. 2021-03-01 GT2 GT2-ST CORVETTE CHANGES #30029weight +100 lbsslower · weightGT2-ST Corvette (-2019) LS2 and L76 5967 gain 100 lbs minimum weight to 3100; 6162 and 7011 variants gain 50–100 lbs; L76 restrictor opens 70 to 73 mm. 2021-03-01 GT2 Request underfloor clarification #30121aeroremoved · aeroGT2 rear engine opening position requirement removed. 2021-03-01 GT2 29742 Change new wording to read as: #30329wordingwordingGT2 Ford Mustang/Thunderbird Boss 302 firing order changes from unrestricted to optional later SBF 302 order 1,3,7,2,6,5,4,8. 2021-02-01 GT2 ABS Restrictions #30064otheraddedGT2 allows ABS braking systems if shown on the individual Spec Line. 2021-02-01 GT2 RM 21-01 C6 & C7 clarification #30192weightslower · weightGT2 Corvette C6 and C7 spec lines split for clarification; C7 LS2, L76, LS3, LT1, LS7 weights raised 100–150 lbs effective 3/1/2021. 2021-01-01 GT2 Request change to engine firing order rule #29742engineadded · engineGT2 Ford Mustang/Thunderbird Boss 302 firing order becomes unrestricted. 2021-01-01 GT2 Request E-46 BMW M3 balance of performance #29833weight -100 lbsfaster · weightGT2 BMW E46 M3 and E36, Z3, and 5000cc V8 minimum weight reduced to 2500 lbs. 2020-12-01 GT2 Request for Bigger Engine in Plymouth Breeze #29380cars addedaddedGT2 Chrysler/Dodge/Plymouth DOHC 2429cc engine classified, 1950 lbs minimum weight.
	Road America Runoffs 20202020-10-02	2:12.806Scott Rettich · fastest of 25 · top 5 within 0.6s	2:13.271Owen McAllister · fastest of 23 · top 5 within 0.7s	143.4Owen McAllister	2:12.298Andrew Aquilante · fastest of 20 · top 5 within 2.9s	2:14.279Andrew Aquilante · fastest of 19 · top 5 within 2.4s	162.2Scotty B White	+1.008squal -0.508s	100.8%qual 99.6%	2:42.209Kyle Greenhill · fastest of 77 · top 5 within 0.5s	2:43.748Preston Pardus · fastest of 75 · top 5 within 1.0s	121.3Kyle Greenhill	+30.477squal +29.403s	122.9%qual 122.1%	2:20.954Calvin Stewart · fastest of 16 · top 5 within 1.8s	2:21.391James Weida · fastest of 14 · top 5 within 1.5s	143.2Aaron Ellis	+8.120squal +8.148s	106.1%qual 106.1%
36 rule changes (FE2: 2, GT2: 26, SM: 2, F5: 6)7 cars added · 7 engine · 7 weight · 1 aero · 1 induction · 1 suspension & brakes · 11 wording · 1 other · F500 Suzuki GSXR600 engine years extended from 2003-2013 to 2003-2019. · GT2 stock car bodies removal rescinded; 1997-current year commercially available stock car bodywork allowed. · GT2 Appendix L section 4.8.4.2.10.3.6 renumbered, eliminating subsections .17–.19. · GT2 TA2 wing width maximum clarified to 65 -5/16 inches, including end plates. · SM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A. · FE2 oil cooler rule clarified: Setrab 50-625-7612 or any cooler with max core 13 inches wide by 6.5 inches high allowed. · GT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line. · Chevrolet Corvette (-2019) GT2-ST permitted LS1/LS6 alternate intake manifold, DORMAN part # 615-900. · GT2 997.2 GT3 Cup minimum weight reduced from 3000 to 2900 lbs. · GT2 BMW E46 M3, E36, Z3, and 5000cc V8 gain Trans Am SGT option: regular shifter 3000 lbs., paddle shifter plus 150 lbs. · GT2 allows up to four hood/fender louvered panels, max 600 sq inches total, min five slots each, ahead of windscreen. · SM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure. · F5 request to adjust external jetting device cockpit control denied; no rule change made. · F5 driver adjustable carburettor mixture: refer to separate Fastrack letter #28359 for ruling. · F5 cockpit adjustment request response published in Fastrack letter 28359. · TA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications. · STO rear wing rules clarify that wicker is called Gurney flap in two places; no performance change. · GT Gurney flap wording clarified: wickerbill and tab terminology replaced with Gurney flap throughout sections 9.1.2.F.7.b. · GT2 Dodge Viper 8.4 OEM minimum weight reduced to 3275 lbs. · GT2 Chevrolet Corvette -2019 OEM minimum weight reduced to 3275 lbs. · GT2 Corvette -2019 LS6 allowed to reduce weight by 50 lbs. · GT2 Panoz GT-S may use TA2 Choice Engine with any 5-speed H-shift transmission. · GT2-ST Corvette LS2 restrictor increases from 70mm to 75mm flat plate; LSX block option added. · GT2-ST Corvette L76 added: 5967cc displacement, 3000 lb minimum weight, 70mm flat plate restrictor. · GT2 Porsche 991.2 GT3 Cup Car engine displacement corrected to 4.0L from 3.8L. · GT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications. · GT2 Chevrolet SS replaces Dodge Charger; all stock car bodies removed from GT2 in 2021. · F500 Honda CBR600RR, Suzuki GSXR600, Yamaha R6 restrictor reduced to 28mm from 29mm. · GTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo. · 991.2 GT3 Cup Car added to GT2 at 3100 lbs with 63mm throttle body restrictor. · GT2 Acura NSX minimum weight cut from 3000 lbs to 2700 lbs. · GT2 Porsche 991.1 GT3 Cup restrictor size increases from 67 mm to 70 mm. · GT2 Porsche 996/997.1 GT3 Cup minimum weight drops to 2800 lbs. · GT2 Corvette -2019 restrictor reduced from 75 mm to 70 mm. · FE minimum weight rises to 1270 lbs; FE2 minimum weight rises to 1270 lbs; new spring options added; tire warmers prohibited.showhide 2020-10-01 F5 Request to Update Suzuki Engine Years for F500 #29453engineadded · engineF500 Suzuki GSXR600 engine years extended from 2003-2013 to 2003-2019. 2020-10-01 GT2 rescind GT2 stock car bodies removal #29219cars addedaddedGT2 stock car bodies removal rescinded; 1997-current year commercially available stock car bodywork allowed. 2020-10-01 GT2 E&O Typos in Appendix L #29447wordingwordingGT2 Appendix L section 4.8.4.2.10.3.6 renumbered, eliminating subsections .17–.19. 2020-10-01 GT2 GT2 wing width wording correction #29469wordingwordingGT2 TA2 wing width maximum clarified to 65 -5/16 inches, including end plates. 2020-10-01 SM Radiator E&O Clarifications #29294wordingwordingSM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A. 2020-09-01 FE2 FE/FE2 Oil Cooler #29293wordingwordingFE2 oil cooler rule clarified: Setrab 50-625-7612 or any cooler with max core 13 inches wide by 6.5 inches high allowed. 2020-09-01 GT2 GT Category Wording #29193wordingaddedGT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line. 2020-09-01 GT2 Corvette GT2-ST intake manifold #29221engineadded · engineChevrolet Corvette (-2019) GT2-ST permitted LS1/LS6 alternate intake manifold, DORMAN part # 615-900. 2020-09-01 GT2 997.2 E&O link to 27915 #29373weightfaster · weightGT2 997.2 GT3 Cup minimum weight reduced from 3000 to 2900 lbs. 2020-08-01 GT2 Request for allowance Trans Am SGT #28951cars addedaddedGT2 BMW E46 M3, E36, Z3, and 5000cc V8 gain Trans Am SGT option: regular shifter 3000 lbs., paddle shifter plus 150 lbs. 2020-08-01 GT2 Omitted GT2 fender/hood openings #29171aeroadded · aeroGT2 allows up to four hood/fender louvered panels, max 600 sq inches total, min five slots each, ahead of windscreen. 2020-08-01 SM Modifications to prevent failures of Rear Brake Caliper Pin #28953suspension & brakessuspension & brakesSM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure. 2020-07-01 F5 Request for Cockpit Adjustment of External Jetting Devices #28359wordingunclearF5 request to adjust external jetting device cockpit control denied; no rule change made. 2020-07-01 F5 Two Stroke Motors (reply to #28359 WDYT) #28816engine 2020-07-01 F5 Re letter requesting driver adjustable carb mixture #28840wordingunclearF5 driver adjustable carburettor mixture: refer to separate Fastrack letter #28359 for ruling. 2020-07-01 F5 #28359 WDYT Request for Cockpit Adjustment #28875wordingunclearF5 cockpit adjustment request response published in Fastrack letter 28359. 2020-07-01 GT2 TA2 Gurney flap wicker clarification #28874wordingwordingTA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications. 2020-07-01 GT2 STO Gurney flap wicker clarification #28883wordingwordingSTO rear wing rules clarify that wicker is called Gurney flap in two places; no performance change. 2020-07-01 GT2 GT Gurney flap wicker clarification #28909wordingwordingGT Gurney flap wording clarified: wickerbill and tab terminology replaced with Gurney flap throughout sections 9.1.2.F.7.b. 2020-06-01 GT2 Request to Adjust Weight of OEM 8.4 Viper #28739weight -50 lbsfaster · weightGT2 Dodge Viper 8.4 OEM minimum weight reduced to 3275 lbs. 2020-06-01 GT2 Request to Adjust Weight of OEM Chevrolet Corvette #28896weight -50 lbsfaster · weightGT2 Chevrolet Corvette -2019 OEM minimum weight reduced to 3275 lbs. 2020-05-01 GT2 Request Corvette engine parity #28576weightfaster · weightGT2 Corvette -2019 LS6 allowed to reduce weight by 50 lbs. 2020-04-01 GT2 Request to revisit Panoz GT-S BoP #28280cars addedaddedGT2 Panoz GT-S may use TA2 Choice Engine with any 5-speed H-shift transmission. 2020-04-01 GT2 GT2-ST Corvette LS2 & L76 #28583enginefaster · engineGT2-ST Corvette LS2 restrictor increases from 70mm to 75mm flat plate; LSX block option added. 2020-04-01 GT2 GT2-ST Corvette L76 #28584cars addedaddedGT2-ST Corvette L76 added: 5967cc displacement, 3000 lb minimum weight, 70mm flat plate restrictor. 2020-03-01 GT2 Request 991.2 Porsche engine displacement verify typo #28194enginefaster · engineGT2 Porsche 991.2 GT3 Cup Car engine displacement corrected to 4.0L from 3.8L. 2020-02-01 GT2 Windshield Clips #27323otheraddedGT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications. 2020-02-01 GT2 Request to Add Chevrolet SS Body to Appendix L #27898cars addedremoved · cars addedGT2 Chevrolet SS replaces Dodge Charger; all stock car bodies removed from GT2 in 2021. 2020-01-01 F5 Change 600cc restrictor size #27883inductionslower · inductionF500 Honda CBR600RR, Suzuki GSXR600, Yamaha R6 restrictor reduced to 28mm from 29mm. 2020-01-01 GT2 Request Factory Five Daytona coupe classification #26308cars addedaddedGTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo. 2020-01-01 GT2 Porsche 991.2 GT3 Cup GT2 Classification #27701cars addedadded991.2 GT3 Cup Car added to GT2 at 3100 lbs with 63mm throttle body restrictor. 2020-01-01 GT2 Request for Acura NSX Spec Line Changes #27755weightfaster · weightGT2 Acura NSX minimum weight cut from 3000 lbs to 2700 lbs. 2020-01-01 GT2 GT2 991.1 restrictor size change #27914enginefaster · engineGT2 Porsche 991.1 GT3 Cup restrictor size increases from 67 mm to 70 mm. 2020-01-01 GT2 GT2 996/997.1 weight change #27915weight -100 lbsfaster · weightGT2 Porsche 996/997.1 GT3 Cup minimum weight drops to 2800 lbs. 2020-01-01 GT2 GT2/ST Corvette comp adjustment #27920engineslower · engineGT2 Corvette -2019 restrictor reduced from 75 mm to 70 mm. 2019-12-01 FE2 FE / FE2 Update Rules #27624weightslower · weightFE minimum weight rises to 1270 lbs; FE2 minimum weight rises to 1270 lbs; new spring options added; tire warmers prohibited.
	Virginia International Raceway Runoffs 20192019-10-05	1:51.062Liam Snyder · fastest of 20 · top 5 within 1.3s	1:52.154Liam Snyder · fastest of 19 · top 5 within 0.7s	142.6Robert Vanman	1:50.182Andrew Aquilante · fastest of 24 · top 5 within 4.5s	1:52.475Andrew Aquilante · fastest of 19 · top 5 within 3.3s	162.8Tom Patton	+0.321squal -0.880s	100.3%qual 99.2%	2:14.552Todd Buras · fastest of 60 · top 5 within 0.2s	2:16.459Elivan Goulart · fastest of 56 · top 5 within 0.4s	119.8Jim Drago	+24.305squal +23.490s	121.7%qual 121.2%	1:57.361Wiley Mcmahan · fastest of 15 · top 5 within 3.8s	1:57.572Wiley Mcmahan · fastest of 15 · top 5 within 4.0s	142.8Eric McRee	+5.418squal +6.299s	104.8%qual 105.7%
26 rule changes (GT2: 21, SM: 4, F5: 1)10 cars added · 6 weight · 1 aero · 1 engine · 5 wording · 3 other · F500 Honda CBR600RR, Suzuki GSXR600, and Yamaha R6 minimum weights increase to 900 lbs. · GT2 TA2 cars must meet 2930 lbs minimum weight per current Trans Am rules or Appendix L. · GT2-ST Toyota Supra 3SGTE added: 2.0L, 2900 lbs minimum weight, 43mm restrictor. · Acura NSX all years classified to GT2-ST: 3.5L turbocharged, 3000 lbs minimum, 43mm restrictor, specific aero and turbo required. · GT2 TA2 minimum weight increases 100 lbs to 2930 pounds. · GT2 BMW E36/E46 M3 and Z3: 4.5L V8 permitted at 2950 lbs, 5.0L V8 at 3000 lbs, plus Flossman body kit allowed. · GTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. · GTX adds Ligier JS2 R classification with restrictor and minimum weight. · GT2 Ford Mustang 5.2L classified at 3300 lbs minimum weight, 82mm single throttle body, carbon fiber body parts allowed. · GT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate. · GT2/ST Porsche Cayman eligible model years extended from 2005–2011 to 2005–2015. · GT2 Porsche Cayman adds 4.0L with 65mm flat plate restrictor at 2700 lbs minimum weight. · SM fuel pump and filter now permitted as Mazda or OEM equivalent part. · SM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified. · SM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted. · SM tire tread protrusion language removed from GCR 9.1.7.C.5. · GT2 BMW E46 M3, E36, Z3, and 5000cc V8 may now use Flossman body kit. · GT2 TA2 clarifies rules; shock caps to $850, brake calipers to $550, pads to $250/axle, wheels to $175 each; allows carbon fiber rear wing; engine setback 21.75 inches max (A–F) or 24 inches (G); carbureted engine displacement 366 cubic in… · GT2 adds BMW 1 Series E82 2008–2012 with N52B30 engine, 2996 cc, 2140 lbs minimum weight. · GT2 Porsche Cayman 05-11 minimum weight drops to 2800 lbs; STO and X51 motor variants noted at 2950 and 2850 lbs. · GT2 Ford Mustang 05- with Ford Racing 5.2l Aluminator engine classified: 5200cc displacement, 3400 lbs minimum weight, 2×41mm flat plate restrictor. · GT2 Porsche 996/997.1 GT3 Cup: add 3.6L displacement and 2900 lbs minimum weight; remove aftermarket exhaust header allowance for 996. · GT2 Ford Mustang FP350S minimum weight reduced 100 lbs to 3400. · GT2 Ford Mustang 05- EcoBoost added: 3500 cc, 3200 lbs minimum, 41 mm restrictor. · GT2 Mazda RX7 Downing GTS body kit allowed without 75 lbs. weight penalty. · GTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs.showhide 2019-08-31 F5 Request for Weight Increase for Motorcycle Powered Cars #27214weight +25 lbsslower · weightF500 Honda CBR600RR, Suzuki GSXR600, and Yamaha R6 minimum weights increase to 900 lbs. 2019-07-01 GT2 TA2 Weight Clarification #27077weightslower · weightGT2 TA2 cars must meet 2930 lbs minimum weight per current Trans Am rules or Appendix L. 2019-05-31 GT2 Request to classify Toyota Supra with 3SGTE engine #25185cars addedaddedGT2-ST Toyota Supra 3SGTE added: 2.0L, 2900 lbs minimum weight, 43mm restrictor. 2019-05-31 GT2 Request to Classify Acura NSX from T1 to GT2? #26121cars addedaddedAcura NSX all years classified to GT2-ST: 3.5L turbocharged, 3000 lbs minimum, 43mm restrictor, specific aero and turbo required. 2019-05-31 GT2 Request for TA2 BOP in GT2 #26509weightslower · weightGT2 TA2 minimum weight increases 100 lbs to 2930 pounds. 2019-05-01 GT2 Request for e36/e46 bmw 4500 cc v8 at 2950lbs in GT2/ST #26106cars addedaddedGT2 BMW E36/E46 M3 and Z3: 4.5L V8 permitted at 2950 lbs, 5.0L V8 at 3000 lbs, plus Flossman body kit allowed. 2019-05-01 GT2 Request GTX Fuel injection for previous GT-1 tube frame cars #26141engineadded · engineGTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. 2019-05-01 GT2 Request to Classify Ligier JS2 R #26535cars addedaddedGTX adds Ligier JS2 R classification with restrictor and minimum weight. 2019-04-01 GT2 Request Ford Perfomance 5.2L crate engine FPR clarification #26159cars addedaddedGT2 Ford Mustang 5.2L classified at 3300 lbs minimum weight, 82mm single throttle body, carbon fiber body parts allowed. 2019-04-01 GT2 Request Ride Height Clarification #26600wordingfasterGT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate. 2019-03-01 GT2 Request Porsche Cayman year classification #26241cars addedaddedGT2/ST Porsche Cayman eligible model years extended from 2005–2011 to 2005–2015. 2019-03-01 GT2 GT2/ST Porsche Cayman engine #26250cars addedaddedGT2 Porsche Cayman adds 4.0L with 65mm flat plate restrictor at 2700 lbs minimum weight. 2019-03-01 SM Request to allow aftermarket fuel filters. #26370otheraddedSM fuel pump and filter now permitted as Mazda or OEM equivalent part. 2019-02-01 SM Request 99-00 replacement Wire harnesses #25602otheraddedSM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified. 2019-02-01 SM Organize and Clarify 9.1.7.C.1.o. #25913wordingwordingSM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted. 2019-02-01 SM Strike Tire Tread Language #26123wordingremovedSM tire tread protrusion language removed from GCR 9.1.7.C.5. 2019-01-01 GT2 ST/GT2 BMW Flossman Kit Clarification #22138aeroadded · aeroGT2 BMW E46 M3, E36, Z3, and 5000cc V8 may now use Flossman body kit. 2019-01-01 GT2 Request Clarification/Revision of Appendix L (2013 TA2 Rules) #25110wordingwordingGT2 TA2 clarifies rules; shock caps to $850, brake calipers to $550, pads to $250/axle, wheels to $175 each; allows carbon fiber rear wing; engine setback 21.75 inches max (A–F) or 24 inches (G); carbureted engine displacement 366 cubic in… 2019-01-01 GT2 Request to classify BMW E82 (1 series) into GT2 #25539cars addedaddedGT2 adds BMW 1 Series E82 2008–2012 with N52B30 engine, 2996 cc, 2140 lbs minimum weight. 2019-01-01 GT2 2010 Cayman Street Tuner Into an STO Car,Addendum #25545weightfaster · weightGT2 Porsche Cayman 05-11 minimum weight drops to 2800 lbs; STO and X51 motor variants noted at 2950 and 2850 lbs. 2019-01-01 GT2 Request - Classify Ford Performance 5.2l #25716cars addedaddedGT2 Ford Mustang 05- with Ford Racing 5.2l Aluminator engine classified: 5200cc displacement, 3400 lbs minimum weight, 2×41mm flat plate restrictor. 2019-01-01 GT2 Add missing displacement, minimum weight. Remove #25765wordingwordingGT2 Porsche 996/997.1 GT3 Cup: add 3.6L displacement and 2900 lbs minimum weight; remove aftermarket exhaust header allowance for 996. 2019-01-01 GT2 Request for Ford FP 350s Weight Reduction #25806weightfaster · weightGT2 Ford Mustang FP350S minimum weight reduced 100 lbs to 3400. 2019-01-01 GT2 Request to Classify EcoBoost Mustang #25842cars addedaddedGT2 Ford Mustang 05- EcoBoost added: 3500 cc, 3200 lbs minimum, 41 mm restrictor. 2019-01-01 GT2 Request to Remove Mazda RX 7 Body Work Penalty #26024weightfaster · weightGT2 Mazda RX7 Downing GTS body kit allowed without 75 lbs. weight penalty. 2019-01-01 GT2 GTX Homologation table update #26034otherunclearGTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs.
	Sonoma Raceway Runoffs 20182018-10-10	1:35.040Flinn Lazier · fastest of 9 · top 5 within 1.5s	1:35.563Flinn Lazier · fastest of 9 · top 5 within 1.7s	126.8Scott Rettich	1:37.203Andrew Aquilante · fastest of 22 · top 5 within 2.1s	1:38.524R Spencer Trenery · fastest of 19 · top 5 within 1.3s	133.8Michael McAleenan	+2.961squal +2.163s	103.1%qual 102.3%	1:54.355Ken Sutherland · fastest of 48 · top 5 within 0.7s	1:55.278Michael Carter · fastest of 48 · top 5 within 0.3s	102.2Danny Steyn	+19.715squal +19.315s	120.6%qual 120.3%	1:41.807Jeff Jorgenson · fastest of 5 · top 5 within 6.6s	1:42.491David Lapham · fastest of 5 · top 5 within 9.5s	113.3David Lapham	+6.928squal +6.767s	107.2%qual 107.1%
No rule changes on record between these events
	Indianapolis Motor Speedway Runoffs 20172017-09-25				1:39.919Andrew Aquilante · fastest of 36 · top 5 within 2.9s	1:40.976Andrew Aquilante · fastest of 35 · top 5 within 2.6s				1:58.306Chris Haldeman · fastest of 86 · top 5 within 0.5s	1:59.100Michael Gagliardo · fastest of 83 · top 5 within 0.6s				1:43.136Wiley Clinton McMahan · fastest of 38 · top 5 within 1.4s	1:42.860Wiley Clinton McMahan · fastest of 37 · top 5 within 1.6s
No rule changes on record between these events
	Mid-Ohio Sports Car Course Runoffs 20162016-09-19				1:25.405Andrew Aquilante · fastest of 21 · top 5 within 2.8s	1:26.847Andrew Aquilante · fastest of 19 · top 5 within 1.5s				1:40.514Justin Hille · fastest of 45 · top 5 within 0.3s	1:40.764Michael Carter · fastest of 44 · top 5 within 0.3s				1:28.528Calvin Stewart · fastest of 14 · top 5 within 3.9s	1:29.853Steven Thompson · fastest of 12 · top 5 within 4.5s
No rule changes on record between these events
	Daytona International Speedway Runoffs 20152015-09-21				1:53.652Jordan Bupp · fastest of 27 · top 5 within 1.2s	1:53.543Jordan Bupp · fastest of 22 · top 5 within 1.7s				2:18.661Andrew Carbonell · fastest of 62 · top 5 within 0.6s	2:24.067Todd Lamb · fastest of 59 · top 5 within 0.8s				2:01.824W. Clint McMahan · fastest of 16 · top 5 within 3.0s	2:03.298Matthew Strand · fastest of 15 · top 5 within 4.9s

By track

Track	Events	Typical % of FE2	Best	Latest
Road America	4	100.0%	100.0%Runoffs 2020	100.0%Runoffs 2026
Virginia International Raceway	3	100.0%	100.0%Runoffs 2019	100.0%Runoffs 2023
Indianapolis Motor Speedway	2	100.0%1 of 2 with FE2	100.0%Runoffs 2021	100.0%Runoffs 2021
Daytona International Speedway	1	0 of 1 with FE2
Mid-Ohio Sports Car Course	1	0 of 1 with FE2
Sonoma Raceway	1	100.0%	100.0%Runoffs 2018	100.0%Runoffs 2018

About this data

Every event the class ran, at any track, oldest to newest on the chart and newest first in the table. Each point is the class's best lap as a share of FE2's best on the same day: the weather, the track and its configuration cancel out, so one figure compares across tracks and years where lap times cannot. It still moves when the yardstick's own balance changes or its field thins, and an event the yardstick did not run has no point. A best from fewer than three cars is greyed. The rule changes that took effect between two events are folded between their rows.