BoP Lab / Classes / F5

F5 vs GTL vs FM vs SM pace at every track

Lap times across years say as much about the weather as the class. % of F5 is each class's best lap as a share of F5'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-SpecEPF5×FAFCFE2FFvsFM ×FPFVFXGT1GT2vsGTL ×GTXHPPP2vsSM ×SMXSRF3STLSTUT1T2T3T4Show 48 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: F5 1:28.528 Calvin Stewart, Runoffs 2016 qualifying · GTL 1:35.377 Wilson Wright, Runoffs 2016 qualifying · FM 1:26.043 Jacob Loomis, Runoffs 2016 qualifying · SM 1:40.514 Justin Hille, Runoffs 2016 qualifying

% of F5Lap times

F5GTLFMSMsolid race · dashed qualifying · slower is lower

F5GTLFMSMsolid race · dashed qualifying · each class's best lap as a share of F5's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker

	Event	F5			GTL					FM					SM
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs F5	% of F5	Qual best	Race best	Trap	vs F5	% of F5	Qual best	Race best	Trap	vs F5	% of F5
	Road America Runoffs 20262026-09-28														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%)
3 rule changes (GTL: 1, SM: 2)1 cars added · 1 wording · 1 other · SM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361. · SM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. · GT3U class removed from GCR; GT3U cars now compete in STU.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. 2026-04-01 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 GTL Remove GT3U from GCR as it is now in STU #39862cars addedremovedcars addedGT3U class removed from GCR; GT3U cars now compete in STU.
	Road America Runoffs 20252025-09-29														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%)
7 rule changes (GTL: 3, SM: 4)2 engine · 4 wording · 1 other · 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. · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit. · 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. · GTL Toyota G16E-GTS removes direct injection prohibition, allowing direct injection engines. · GTL L16 limited prep gains 32mm choke option at 1910 lbs, compression capped 12.0:1, valve lift .450 max.showhide 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. 2025-01-01 GTL Correct language regarding OEM Areo Devices #37137wordingwordingTA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit. 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. 2024-11-01 GTL G16E-GTS Fuel Injection Spec Line Change #36588engineaddedengineGTL Toyota G16E-GTS removes direct injection prohibition, allowing direct injection engines. 2024-11-01 GTL GTL Alternate Weight and Choke Option for L16 engine #36653engineaddedengineGTL L16 limited prep gains 32mm choke option at 1910 lbs, compression capped 12.0:1, valve lift .450 max.
	Road America Runoffs 20242024-10-01				2:30.858Peter Shadowen · fastest of 14 · top 5 within 4.4s-1.085s (-0.71%)	2:30.844Chris Bovis · fastest of 13 · top 5 within 3.7s-0.757s (-0.50%)	133.3Peter Shadowen+1.8 mph (+1.4%)								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%)
20 rule changes (GTL: 16, SM: 4)5 cars added · 4 engine · 3 weight · 1 aero · 1 induction · 4 wording · 2 other · GTL adds Toyota GR86 2021–2023, 2dr RWD, 101.3 in wheelbase. · GTL adds Spec Miata 1990–2005 with legal Spec Miata engine and intake system. · GTL adds Mazda MX5 RF 2017- model with 91.0 in wheelbase. · 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. · GTL added to GT3 choke option line in GCR 9.1.2.E.13.n. · GT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR. · GTL Datsun 510 Limited Prep fuel induction increased to 34 mm chokes, minimum weight rises to 2000 lbs. · 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 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E. · GTL 12A rotary engines may machine and use 13B housing to O.E. 12A spec across all port types. · GTL Toyota DR86 2021–2024 added to class. · GTL BMW Mini model years changed to 2002-2013. · GTL small unrestricted engines under 1399cc lose 38–79 lbs across Alfa, AMC, Triumph, Mini, Sprite, Fiat, Ford, Honda, Mazda, Nissan, Subaru, Toyota, Volkswagen. · GTL Honda Fit 2009-13 2-door FWD added with 99.0 in wheelbase, alternate 94.0 and 97.0 in. · 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. · GTL Nissan Sentra/200SX A 1400 minimum weight reduced to 1800 lbs.showhide 2024-09-01 GTL Request to Include Toyota GR86 in GTL #36324cars addedaddedGTL adds Toyota GR86 2021–2023, 2dr RWD, 101.3 in wheelbase. 2024-09-01 GTL Inclusion of Modified Spec Miata for GTL competition #36325cars addedaddedGTL adds Spec Miata 1990–2005 with legal Spec Miata engine and intake system. 2024-09-01 GTL Include Mazda MX5 RF 2017- in GTL #36428cars addedaddedGTL adds Mazda MX5 RF 2017- model with 91.0 in wheelbase. 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 #36556engineaddedengineSM 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 GTL Add GTL to GT3 choke option line. #36236otheraddedGTL added to GT3 choke option line in GCR 9.1.2.E.13.n. 2024-05-01 GTL Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslowerweightGT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR. 2024-05-01 GTL Allow 34 mm chokes for the Datsun 510 #35661induction +50 lbsfasterinductionGTL Datsun 510 Limited Prep fuel induction increased to 34 mm chokes, minimum weight rises to 2000 lbs. 2024-02-01 GTL 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 GTL GT Direct Injection allowance and rules #35437engineaddedengineGT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment. 2024-02-01 GTL GT2/3 remove Direction Injection not allowed in Spec line notes #35439engineaddedengineGT2 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 GTL Rotary Engine 12A Rotor Housings #35131engineaddedengineGTL 12A rotary engines may machine and use 13B housing to O.E. 12A spec across all port types. 2024-01-01 GTL Request to Include Toyota GR86 in GTL #35198cars addedaddedGTL Toyota DR86 2021–2024 added to class. 2024-01-01 GTL Errors and Omissions, GTL engines & Cars #35226wordingwordingGTL BMW Mini model years changed to 2002-2013. 2023-12-01 GTL Small Engines in GT Lite #34842weightfasterweightGTL small unrestricted engines under 1399cc lose 38–79 lbs across Alfa, AMC, Triumph, Mini, Sprite, Fiat, Ford, Honda, Mazda, Nissan, Subaru, Toyota, Volkswagen. 2023-12-01 GTL Request to Classify Honda Fit body in GTL #35020cars addedaddedGTL Honda Fit 2009-13 2-door FWD added with 99.0 in wheelbase, alternate 94.0 and 97.0 in. 2023-12-01 GTL 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. 2023-11-01 GTL Weight for Nissan Sentra/200SX A 1400's #34918weight -50 lbsfasterweightGTL Nissan Sentra/200SX A 1400 minimum weight reduced to 1800 lbs.
	Virginia International Raceway Runoffs 20232023-09-23				2:09.564Peter Shadowen · fastest of 11 · top 5 within 4.9s+1.775s (+1.39%)	2:11.277Graham Fuller · fastest of 10 · top 5 within 2.4s-9.903s (-7.01%)	142.7Peter Shadowen+6.7 mph (+4.9%)								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%)
8 rule changes (GTL: 7, SM: 1)4 cars added · 2 weight · 1 engine · 1 wording · Fields Cardinal V8 added to GT1 with Ford V8 engine, 4.9L, 2100 lbs, fuel injection. · GTL 3K, 4K, 5K Toyota engines may now use 4Y block only. · GT2 and GTL add Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines as permitted options. · SM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. · GTL Fiat X1/9 1500 Limited Prep minimum weight increases to 2000 lbs from 1835 lbs. · GT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870. · GTL adds Ford Festiva 1988-1993 FWD hatchback with Mazda B3 1324cc engine. · GTL adds Toyota G16E-GTS 1618cc DOHC 3-cyl engine, 1945 lbs, SIR, no turbo or direct injection.showhide 2023-05-01 GTL Please classify Fields Cardinal V8 #33784cars addedaddedFields Cardinal V8 added to GT1 with Ford V8 engine, 4.9L, 2100 lbs, fuel injection. 2023-02-01 GTL Toyota 4Y Engine Classification Request #33562engineaddedengineGTL 3K, 4K, 5K Toyota engines may now use 4Y block only. 2023-01-01 GTL 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 SM BOP for NB1 and NB2 #32309weightslowerweightSM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. 2022-12-01 GTL Fiat HP Limited Prep X1/9 Weight in GTL #33297weightslowerweightGTL Fiat X1/9 1500 Limited Prep minimum weight increases to 2000 lbs from 1835 lbs. 2022-12-01 GTL 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 GTL Request to add Ford Festiva to GTL #33335cars addedaddedGTL adds Ford Festiva 1988-1993 FWD hatchback with Mazda B3 1324cc engine. 2022-11-01 GTL Engine Request #33064cars addedaddedGTL adds Toyota G16E-GTS 1618cc DOHC 3-cyl engine, 1945 lbs, SIR, no turbo or direct injection.
	Virginia International Raceway Runoffs 20222022-09-24	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%)	2:07.789Peter Shadowen · fastest of 14 · top 5 within 2.2s+0.792s (+0.62%)	2:21.180Michael Lewis · fastest of 13 · top 5 within 2.1s+13.343s (+10.44%)	136.0Peter Shadowen+4.9 mph (+3.7%)	-0.682squal +10.100s	99.5%qual 108.6%						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%)	-2.755squal +16.975s	98.1%qual 114.4%
10 rule changes (F5: 6, GTL: 3, SM: 1)2 cars added · 1 engine · 5 wording · 2 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. · F500 Rotax engines now permit Ingi Tech Sparker ignition DCP-CDI-P2 as alternate ECU. · 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. · 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 GTL with Ford Zetec 1796cc engine, 2050 lbs minimum weight, 22.5mm SIR. · F5 cars must install AIM part #X47KPFSOLO2R0 data box mount for Majors and Runoffs. · 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 GTL 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. 2022-08-01 F5 Ensure availability of ECU for Rotax engines #32695engineaddedengineF500 Rotax engines now permit Ingi Tech Sparker ignition DCP-CDI-P2 as alternate ECU. 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. 2022-04-01 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 GTL Request to Classify Ginetta G40 in GTL #31599cars addedaddedGinetta G40 added to GTL with Ford Zetec 1796cc engine, 2050 lbs minimum weight, 22.5mm SIR. 2022-01-01 F5 Data Box Mounting Plate #31638otheraddedF5 cars must install AIM part #X47KPFSOLO2R0 data box mount for Majors and Runoffs. 2021-10-01 GTL 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	1:42.619Ryan 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	1:51.819Christopher Bovis · fastest of 22 · top 5 within 1.8s+1.488s (+1.35%)	1:51.952Scott Twomey · fastest of 19 · top 5 within 1.7s-0.116s (-0.10%)	129.5Brian Linn	+8.812squal +9.200s	108.5%qual 109.0%						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	+15.697squal +15.076s	115.2%qual 114.7%
12 rule changes (F5: 3, GTL: 8, SM: 1)4 cars added · 2 induction · 1 aero · 4 wording · 1 other · 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. · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two locations and 6010 to 6014X in TA2 Appendix. · GTL Honda B18 split into B18A/B at 1797 cc 2050 lbs and B18C at 1834 cc 2065 lbs. · GTL Nissan B13 Sentra may have hood bulge maximum 1.5 inches high by 10.0 long by 6.0 wide. · unclear · F500 Rotax 593 HO engine now permitted; 875 lbs minimum weight, MA0242SP1020A or MA0242SP1063A restrictor, specific intake boots and piston required. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. · GTL Mazda 12A SIR increases to 29mm, minimum weight rises to 2000 lbs, 28mm SIR option with 175 lb penalty removed. · GTL adds FIAT X-1/9 Bertone 1500 SOHC, 1498 cc, 2000 lbs, fuel injection or carburetors permitted. · GTL Nissan MRA8DE 1.8L engine added, 1797 cc, DOHC, 2050 lbs minimum weight. · GTL Mazda 13B SIR increases from 26 mm to 28 mm; 27 mm option with 175 lbs removed.showhide 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 GTL 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. 2021-07-01 GTL Request clarification for the Honda B18a,bVS B18c #30482cars addedaddedGTL Honda B18 split into B18A/B at 1797 cc 2050 lbs and B18C at 1834 cc 2065 lbs. 2021-07-01 GTL Request to Allow Hood Bulge on Nissan B13 Sentra #30504aeroaddedaeroGTL Nissan B13 Sentra may have hood bulge maximum 1.5 inches high by 10.0 long by 6.0 wide. 2021-07-01 GTL Request BMW E21 Classing #30582otherunclearunclear 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 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 GTL Request for Help for Mazda 12A #29754induction +50 lbsslowerinductionGTL Mazda 12A SIR increases to 29mm, minimum weight rises to 2000 lbs, 28mm SIR option with 175 lb penalty removed. 2021-02-01 GTL Request LP HP Fiat X1/9 & Bertone 1500 to GTL #30058cars addedaddedGTL adds FIAT X-1/9 Bertone 1500 SOHC, 1498 cc, 2000 lbs, fuel injection or carburetors permitted. 2021-01-01 GTL Please Add GTL Nissan 1.8L Engine MRA8DE #29805cars addedaddedGTL Nissan MRA8DE 1.8L engine added, 1797 cc, DOHC, 2050 lbs minimum weight. 2021-01-01 GTL Increase 13b SIR size #29867inductionfasterinductionGTL Mazda 13B SIR increases from 26 mm to 28 mm; 27 mm option with 175 lbs removed.
	Road America Runoffs 20202020-10-02	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	2:31.943Chris Bovis · fastest of 14 · top 5 within 6.3s	2:31.601Peter Shadowen · fastest of 14 · top 5 within 7.2s	131.4Peter Shadowen	+10.210squal +10.989s	107.2%qual 107.8%						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	+22.357squal +21.255s	115.8%qual 115.1%
25 rule changes (F5: 6, GTL: 17, SM: 2)4 aero · 3 cars added · 2 engine · 2 induction · 2 suspension & brakes · 1 weight · 10 wording · 1 other · F500 Suzuki GSXR600 engine years extended from 2003-2013 to 2003-2019. · 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. · GT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line. · GTL Mazda 13B restrictor increases from 24mm to 26mm SIR, minimum weight rises to 2125 lbs, alternative 27mm SIR option adds 175 lbs. · 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. · GTL: Toyota MR2 Spyder 1999–2007 newly classified for GTL competition. · 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. · GTL Mazda 13B restrictor size addressed in response to letter 28518; see that letter for details. · GTL SIR stall test procedure clarified: system tested as raced, competitor must prevent air bypass behind restrictor. · GTL wing mount openings excluded from square inch area limit. · GTL wing mounting posts limited to 85 square inches exposed area each, measured flat from side view. · GTL wing mounting posts limited to 85 square inches each, measured flat from side view. · GTL wing endplates maximum area increased to 64 square inches from 8.5 by 3.0 inches rectangle. · GTL Mazda 12A street port minimum weight drops to 1950 lbs. · GT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications. · 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. · GTL adds Jetta Mk1 two-door classification effective 2020-01-01. · GTL Honda CRX 84-87 and 88-91 lose permission to use IRS with 2.5% weight penalty.showhide 2020-10-01 F5 Request to Update Suzuki Engine Years for F500 #29453engineaddedengineF500 Suzuki GSXR600 engine years extended from 2003-2013 to 2003-2019. 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 GTL GT Category Wording #29193wordingaddedGT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line. 2020-08-01 GTL Request to change the Mazda 13b restrictor size #28518induction +175 lbsfasterinductionGTL Mazda 13B restrictor increases from 24mm to 26mm SIR, minimum weight rises to 2125 lbs, alternative 27mm SIR option adds 175 lbs. 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 GTL Request to classify 1999-2007 Toyota MR2 Spyder body #28870cars addedaddedGTL: Toyota MR2 Spyder 1999–2007 newly classified for GTL competition. 2020-07-01 GTL TA2 Gurney flap wicker clarification #28874wordingwordingTA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications. 2020-07-01 GTL 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 GTL 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. 2020-07-01 GTL Mazda 13b Restrictor Size Follow up to Letter 28518 #29015wordingunclearGTL Mazda 13B restrictor size addressed in response to letter 28518; see that letter for details. 2020-06-01 GTL Stall Test #28709wordingwordingGTL SIR stall test procedure clarified: system tested as raced, competitor must prevent air bypass behind restrictor. 2020-05-01 GTL GTL Wing Rule #28754aeroaddedaeroGTL wing mount openings excluded from square inch area limit. 2020-03-01 GTL Wing Mounting Upright Size #27641aeroaeroGTL wing mounting posts limited to 85 square inches exposed area each, measured flat from side view. 2020-03-01 GTL Wing Mounting Upright Size #27641aeroaeroGTL wing mounting posts limited to 85 square inches each, measured flat from side view. 2020-03-01 GTL GTL wing end plates addition #28243aerofasteraeroGTL wing endplates maximum area increased to 64 square inches from 8.5 by 3.0 inches rectangle. 2020-03-01 GTL Clarification to letter #27406 #28309weight -50 lbsfasterweightGTL Mazda 12A street port minimum weight drops to 1950 lbs. 2020-02-01 GTL Windshield Clips #27323otheraddedGT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications. 2020-01-01 F5 Change 600cc restrictor size #27883inductionslowerinductionF500 Honda CBR600RR, Suzuki GSXR600, Yamaha R6 restrictor reduced to 28mm from 29mm. 2020-01-01 GTL 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 GTL Request to Classify the MK1 two door Jetta #27648cars addedaddedGTL adds Jetta Mk1 two-door classification effective 2020-01-01. 2019-12-01 GTL 88-91 Honda CRX Spec Line Correction #27233suspension & brakesremovedsuspension & brakesGTL Honda CRX 84-87 and 88-91 lose permission to use IRS with 2.5% weight penalty.
	Virginia International Raceway Runoffs 20192019-10-05	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	2:06.997Peter Shadowen · fastest of 19 · top 5 within 4.0s	2:07.837Bill Ball · fastest of 18 · top 5 within 4.2s	131.1Peter Shadowen	+10.265squal +9.636s	108.7%qual 108.2%	1:55.124Bryce Cornet · fastest of 8 · top 5 within 2.3s	2:15.816Bryce Cornet · fastest of 8 · top 5 within 4.9s	135.7Bryce Cornet	+18.244squal -2.237s	115.5%qual 98.1%	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	+18.887squal +17.191s	116.1%qual 114.6%
18 rule changes (F5: 1, GTL: 13, SM: 4)4 cars added · 2 engine · 2 weight · 1 induction · 1 removed · 5 wording · 3 other · F500 Honda CBR600RR, Suzuki GSXR600, and Yamaha R6 minimum weights increase to 900 lbs. · GTL Fun Cup Beetle engine weight set to 1850 lbs with Weber DMTL 32/34 induction. · GTL Fun Cup Beetle removes reference to VW engine table; Fun Cup engines only permitted. · GTL Honda CRZ 10-14, CRZ 15-16, and Insight 00-06 gain alternate wheelbase option of 90.6 inches. · GTL Fun Cup Beetle added, all model years, 2-door RWD, 94.5 in wheelbase, VW Fun Cup spec chassis. · GTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. · GTX adds Ligier JS2 R classification with restrictor and minimum weight. · GTL Mazda 13B may use 25mm SIR with 175 lbs weight penalty added. · GT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate. · GTL Mazda 12A may use 28mm SIR plus 175 lbs. · GTL: Ford Mustang 94-04 body newly classified for GTL racing. · 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. · GTL Mini 1275–1399 Iron and Aluminum Crossflow with OE common sump gearbox reduce weight by 125 lbs, up from 50 lbs. · GTL BMC thru Rover Group removes four long inactive Mini engines: 948, 970, 1071, 1098. · 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 lbsslowerweightF500 Honda CBR600RR, Suzuki GSXR600, and Yamaha R6 minimum weights increase to 900 lbs. 2019-08-31 GTL Fun Cup Beetle #27334wordingwordingGTL Fun Cup Beetle engine weight set to 1850 lbs with Weber DMTL 32/34 induction. 2019-08-01 GTL GTL #26960wordingwordingGTL Fun Cup Beetle removes reference to VW engine table; Fun Cup engines only permitted. 2019-07-01 GTL Request CRZ wheelbase change #26896cars addedaddedGTL Honda CRZ 10-14, CRZ 15-16, and Insight 00-06 gain alternate wheelbase option of 90.6 inches. 2019-05-01 GTL Request to Classify VW Fun Cup Beetle #25986cars addedaddedGTL Fun Cup Beetle added, all model years, 2-door RWD, 94.5 in wheelbase, VW Fun Cup spec chassis. 2019-05-01 GTL Request GTX Fuel injection for previous GT-1 tube frame cars #26141engineaddedengineGTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. 2019-05-01 GTL Request to Classify Ligier JS2 R #26535cars addedaddedGTX adds Ligier JS2 R classification with restrictor and minimum weight. 2019-05-01 GTL Request for GTL Mazda 13B SIR Increase with Penalty #26572engineaddedengineGTL Mazda 13B may use 25mm SIR with 175 lbs weight penalty added. 2019-04-01 GTL 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 GTL Request Mazda 12a Rotary SIR Increase #26081inductionaddedinductionGTL Mazda 12A may use 28mm SIR plus 175 lbs. 2019-03-01 GTL Request to Classify Mustang 2 Body in GTL #26222cars addedaddedGTL: Ford Mustang 94-04 body newly classified for GTL racing. 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 GTL Request for GTL Mini Adjustments #25754weightfasterweightGTL Mini 1275–1399 Iron and Aluminum Crossflow with OE common sump gearbox reduce weight by 125 lbs, up from 50 lbs. 2019-01-01 GTL BMC thru Rover Group remove long inactive mini #25771removedremovedGTL BMC thru Rover Group removes four long inactive Mini engines: 948, 970, 1071, 1098. 2019-01-01 GTL 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	1:41.807Jeff Jorgenson · fastest of 5 · top 5 within 6.6s	1:42.491David Lapham · fastest of 5 · top 5 within 9.5s	113.3David Lapham	1:47.885Troy Ermish · fastest of 20 · top 5 within 4.5s	1:49.458Troy Ermish · fastest of 19 · top 5 within 3.6s	109.3Charles Leonard	+6.967squal +6.078s	106.8%qual 106.0%	1:37.598Bryce Cornet · fastest of 13 · top 5 within 0.9s	1:37.909Bryce Cornet · fastest of 12 · top 5 within 1.3s	124.1Melvin David Kemper Jr	-4.582squal -4.209s	95.5%qual 95.9%	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	+12.787squal +12.548s	112.5%qual 112.3%
No rule changes on record between these events
	Indianapolis Motor Speedway Runoffs 20172017-09-25	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		1:50.331Christopher Bovis · fastest of 26 · top 5 within 1.5s	1:52.068Christopher Bovis · fastest of 20 · top 5 within 1.0s		+9.208squal +7.195s	109.0%qual 107.0%	1:41.231Jarret Voorhies · fastest of 16 · top 5 within 1.7s	1:41.146Jarret Voorhies · fastest of 16 · top 5 within 1.2s		-1.714squal -1.905s	98.3%qual 98.2%	1:58.306Chris Haldeman · fastest of 86 · top 5 within 0.5s	1:59.100Michael Gagliardo · fastest of 83 · top 5 within 0.6s		+16.240squal +15.170s	115.8%qual 114.7%
No rule changes on record between these events
	Mid-Ohio Sports Car Course Runoffs 20162016-09-19	1:28.528Calvin Stewart · fastest of 14 · top 5 within 3.9s	1:29.853Steven Thompson · fastest of 12 · top 5 within 4.5s		1:35.377Wilson Wright · fastest of 28 · top 5 within 1.2s	1:35.912Kyle Disque · fastest of 28 · top 5 within 1.1s		+6.059squal +6.849s	106.7%qual 107.7%	1:26.043Jacob Loomis · fastest of 8 · top 5 within 3.1s	1:27.922Jacob Loomis · fastest of 8 · top 5 within 2.7s		-1.931squal -2.485s	97.9%qual 97.2%	1:40.514Justin Hille · fastest of 45 · top 5 within 0.3s	1:40.764Michael Carter · fastest of 44 · top 5 within 0.3s		+10.911squal +11.986s	112.1%qual 113.5%
No rule changes on record between these events
	Daytona International Speedway Runoffs 20152015-09-21	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		2:11.387Jim Dentici · fastest of 10 · top 5 within 2.2s	2:13.564Jim Dentici · fastest of 9 · top 5 within 2.0s		+10.266squal +9.563s	108.3%qual 107.8%	1:57.804Joseph Burton-Harris · fastest of 10 · top 5 within 2.3s	1:58.029Joseph Burton-Harris · fastest of 10 · top 5 within 1.7s		-5.269squal -4.020s	95.7%qual 96.7%	2:18.661Andrew Carbonell · fastest of 62 · top 5 within 0.6s	2:24.067Todd Lamb · fastest of 59 · top 5 within 0.8s		+20.769squal +16.837s	116.8%qual 113.8%

By track

Track	Events	Typical % of F5	Best	Latest
Road America	4	100.0%1 of 4 with F5	100.0%Runoffs 2020	100.0%Runoffs 2020
Virginia International Raceway	3	100.0%2 of 3 with F5	100.0%Runoffs 2019	100.0%Runoffs 2022
Indianapolis Motor Speedway	2	100.0%	100.0%Runoffs 2017	100.0%Runoffs 2021
Daytona International Speedway	1	100.0%	100.0%Runoffs 2015	100.0%Runoffs 2015
Mid-Ohio Sports Car Course	1	100.0%	100.0%Runoffs 2016	100.0%Runoffs 2016
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 F5's best on the same day: the weather and the day cancel out, so one figure compares across years where lap times cannot; a class that suits one track more than another still reads differently there. 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.