FV vs SRF vs SM vs T2 pace at Michelin Raceway Road Atlanta
Quickest here:FV 1:43.556 Andrew Whitston, Super Tour Mar 2024 race · SM 1:41.798 Danny Steyn, Super Tour Mar 2021 qualifying · T2 1:33.058 Raphael Assuncao, Super Tour Mar 2022 race
FVSRFSMT2solid race · dashed qualifying · slower is lower
FVSRFSMT2solid race · dashed qualifying · each class's best lap as a share of FV's at the same event (the reference class, changeable above); 100% is level, higher is quicker
Event
FV
SRF
SM
T2
Qual best
Race best
Trap
Qual best
Race best
Trap
vs FV
% of FV
Qual best
Race best
Trap
vs FV
% of FV
Qual best
Race best
Trap
vs FV
% of FV
Super Tour Mar 2026 ST26MAR062026-03-06
1:45.061Donnie Isley · fastest of 9 · top 5 within 5.0s+0.537s (+0.51%)
1:46.101Donnie Isley · fastest of 9 · top 5 within 3.6s+2.545s (+2.46%)
107.1Donnie Isley+4.9 mph (+4.8%)
1:42.324Skyler Cottrell · fastest of 52 · top 5 within 0.4s-0.524s (-0.51%)
1:42.611Charles Mactutus · fastest of 51 · top 5 within 0.2s-0.014s (-0.01%)
112.2James Newell+5.2 mph (+4.9%)
-3.490squal -2.737s
96.7%qual 97.4%
1:37.184Raphael Assuncao · fastest of 5 · top 5 within 15.7s+3.299s (+3.51%)
1:34.508William Bolt · fastest of 5 · top 5 within 15.7s-0.196s (-0.21%)
142.3Raphael Assuncao+4.0 mph (+2.9%)
-11.593squal -7.877s
89.1%qual 92.5%
34 rule changes (SRF: 4, SM: 3, T2: 27)6 weight · 5 induction · 4 cars added · 3 suspension & brakes · 3 tyres & wheels · 2 engine · 1 aero · 4 wording · 6 other · SRF3 spark plugs limited to NGK LTR7IX-11 P/N G301041 only; washers and sealing rings prohibited. · SRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted. · 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. · SRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only. · SRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward.showhide
SRF SRF3 Spark Plugs #39899engineengineSRF3 spark plugs limited to NGK LTR7IX-11 P/N G301041 only; washers and sealing rings prohibited.
SM SMX Data Submission - Penalties #38248otheraddedSMX drivers must submit data acquisition files on time or face suspension and $250 fine.
SM Committee) SMX Penaly Clarification updated language #38337wordingwordingSMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines.
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.
SRF Driver Safety & Comfort #37966otheraddedSRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only.
SRF Update SADEV transmission specs #37992wordingwordingSRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward.
T2 Please class the Darkhorse R in T2 #37295cars added
1:42.848Sean Noonan · fastest of 35 · top 5 within 0.2s+0.228s (+0.22%)
1:42.625Sean Noonan · fastest of 33 · top 5 within 0.6s-0.370s (-0.36%)
107.0Sean Noonan+1.8 mph (+1.7%)
1:33.885Raphael Assuncao · fastest of 4 · top 4 within 13.9s-2.790s (-2.89%)
1:34.704Raphael Assuncao · fastest of 4 · top 4 within 4.9s-2.078s (-2.15%)
138.3Raphael Assuncao+9.4 mph (+7.3%)
44 rule changes (FV: 1, SRF: 6, SM: 5, T2: 32)6 suspension & brakes · 5 induction · 5 weight · 4 cars added · 4 engine · 4 tyres & wheels · 2 removed · 8 wording · 6 other · 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. · FV ferrous rotor must not be cross-drilled; pad cleaning grooves limit unchanged at three per side. · SRF3 air filter rule removes K&N RC-9160 option, specifies Weems P/N WM301020 only. · SRF Wilwood vented rotor minimum thickness increases to 13.25mm, 0.522 inches. · SRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front. · 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. · FE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure. · SRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement. · SRF wet tyres: front P185/60R13 H20 or W2 and rear P205/60R13 H20 or W2 removed; front P185/65R13 W2 and rear P205/60R13 W2 now required. Hoosier decal placement specified.showhide
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.
SRF Hoosier Tire Decal Placement #36739wordingwordingSRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front.
SM SMX Camera Rule Correction #36496wordingwordingSMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification.
SM Committee) AIM ECU Protocol #36556engineadded · engineSM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 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.
SM Committee) Shifter Bushing #36611otheraddedSM and SMX now allow an alternate shifter bushing at the bottom of the shift lever.
SRF Protest Fee Clarification #36540wordingwordingFE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure.
SRF Update to Letter 36619 with new Hoosier Contingency Decal Info #36624wordingwordingSRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement.
SRF Update Rain Tire Rule and Hoosier Decal Placement #36436tyres & wheelstyres & wheelsSRF wet tyres: front P185/60R13 H20 or W2 and rear P205/60R13 H20 or W2 removed; front P185/65R13 W2 and rear P205/60R13 W2 now required. Hoosier decal placement specified.
T2 T2-T4 Set expiration dates on spec lines #35378induction
T2 Reply to letter #35161 and #31661 #35384weight +75 lbs
SRF Update SRF Rain / Brake Rule #34706otherotherSRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch.
SRF Update SRF Brake Light Rule v1 #34853otherotherSRF brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24, with SCCA Enterprises P/N 180427A pigtail and strobing rain light kit.
T2 Ride Height Correction for the T3 Solstice. #34615suspension & brakes
T2 370Z Obsolete Parts & NISMO Alternatives to SPL Parts #34297weight
SRF Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheelstyres & wheelsSRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance.
SRF Update SRF Front W2 Rain Tire Part Number #34118tyres & wheelstyres & wheelsSRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13.
T2 Allowance of any nonmetallic bushing material in T2 #33833suspension & brakes
T2 Allow Adjustable stabilizer bar links #33861suspension & brakes
Super Tour Mar 2023 ST23MAR102023-03-10
1:46.374Mitchell Ferguson · fastest of 6 · top 5 within 3.0s+0.482s (+0.46%)
1:46.209Stevan Davis · fastest of 6 · top 5 within 1.3s+0.338s (+0.32%)
108.5Russell Fredericks+2.5 mph (+2.4%)
1:42.619Charles Mactutus · fastest of 48 · top 5 within 0.7s-0.195s (-0.19%)
1:42.553Charles Mactutus · fastest of 47 · top 5 within 0.4s+0.689s (+0.68%)
112.2Jonathan Neudorf-1.3 mph (-1.2%)
-3.656squal -3.755s
96.6%qual 96.5%
1:36.511James Keown · fastest of 6 · top 5 within 2.1s+1.384s (+1.45%)
1:35.906James Keown · fastest of 5 · top 5 within 2.1s+2.848s (+3.06%)
141.5Scotty B White-5.3 mph (-3.6%)
-10.303squal -9.863s
90.3%qual 90.7%
20 rule changes (SRF: 3, SM: 2, T2: 15)3 tyres & wheels · 3 weight · 2 cars added · 2 engine · 2 suspension & brakes · 2 wording · 6 other · SRF removes 1985 Renault Alliance solid front rotor option; restrictor sizes decrease 1mm for newer Kawasaki and multi-brand engines; minimum weights increase to 1100 lbs. · SM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. · SRF tire rule wording clarified: tires must be run as delivered. · SRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified. · SM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation.showhide
SRF Update SRF Brake Rule #33469enginefaster · engineSRF removes 1985 Renault Alliance solid front rotor option; restrictor sizes decrease 1mm for newer Kawasaki and multi-brand engines; minimum weights increase to 1100 lbs.
T2 Honda Civic Type R Tire Size Increase #33672tyres & wheels
SRF SRF Tire Rule Update #32614wordingwordingSRF tire rule wording clarified: tires must be run as delivered.
SRF Brake, seal, and air filter clarifications #32670otherfasterSRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified.
T2 BMW M235iR/M240iR Min Weight Clarification #32430weight
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.
T2 Request to Allow the Use of Aftermarket ECU's in Touring #31067engine
T2 BMW M2 CS Cup 2020- Exhaust #32243tyres & wheels
1:45.892Mitchell Ferguson · fastest of 8 · top 5 within 3.5s+2.182s (+2.10%)
1:45.871Stevan Davis · fastest of 8 · top 5 within 3.3s+2.124s (+2.05%)
106.0Jeffrey Filipkowski-2.0 mph (-1.9%)
1:42.814Connor Zilisch · fastest of 60 · top 5 within 0.3s+1.016s (+1.00%)
1:41.864Travis Wiley · fastest of 60 · top 5 within 0.7s-0.700s (-0.68%)
113.5Junior Brock-0.1 mph (-0.1%)
-4.007squal -3.078s
96.2%qual 97.1%
1:35.127Raphael Assuncao · fastest of 4 · top 4 within 3.3s+0.337s (+0.36%)
1:33.058Raphael Assuncao · fastest of 4 · top 4 within 2.6s-1.631s (-1.72%)
146.8Raphael Assuncao+3.5 mph (+2.5%)
-12.813squal -10.765s
87.9%qual 89.8%
37 rule changes (FV: 4, SRF: 5, SM: 1, T2: 27)7 suspension & brakes · 6 weight · 5 cars added · 3 engine · 1 induction · 1 tyres & wheels · 6 wording · 8 other · FV connecting rod options expanded to include BrianCrower part BC6417 and Newland Group part 4M113077. · FV connecting rods minimum weight 425.0 grams, center-to-center length 130 +0.10/-0.25 mm; Crower, BrianCrower, Newland Group parts allowed if meeting specs. · FV Crower connecting rods SP93280B and BC6417 allowed as direct replacement, must meet OEM minimum weight. · FV allows Crower SP93280B and Brian Crower Racing Rods connecting rods as direct replacements, matching OEM minimum weight. · SRF wet tyres front P185/65R13 W2 option added; air box clarified as-delivered; SRF3 restrictor plate G301048 mandatory Jan 1 2022; P2 motorcycle engines up to 1005cc with 35mm restrictor, 2009+ stock 1075 lbs, 2008 stock 1025 lbs, modifie… · SRF wet tyres add Hoosier W2 option alongside existing H20 from October 4, 2021. · SRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive. · SRF seal requirements clarified: seals now must be on driveline components in designated locations; unsealed components removed and inspected by CSR or Enterprises rather than engine shipped for testing. · SRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture.showhide
FV Connecting Rod Update Request for 9.1.1.C Formula Vee (FV) 5.C.6 #32160engineadded · engineFV connecting rod options expanded to include BrianCrower part BC6417 and Newland Group part 4M113077.
FV E&O clarification of connecting rod center-to-center length #32183wordingwordingFV connecting rods minimum weight 425.0 grams, center-to-center length 130 +0.10/-0.25 mm; Crower, BrianCrower, Newland Group parts allowed if meeting specs.
T2 Reply to letter #31486/29879 T2-T4 Grill openings #31935suspension & brakes
FV Update direct replacement connecting rod information #31843wordingwordingFV Crower connecting rods SP93280B and BC6417 allowed as direct replacement, must meet OEM minimum weight.
T2 Touring 2 BOP adjustments for 2022 #31480weight -50 lbs
T2 Reply to letter 29879 T2-T4 Grill Openings #31486suspension & brakes
T2 Request to clarify radiator hoses #31682wording
FV Formula V Connecting Rod Replacement #31448engineadded · engineFV allows Crower SP93280B and Brian Crower Racing Rods connecting rods as direct replacements, matching OEM minimum weight.
SRF Three Updates to SRF Rules #31523otherotherSRF wet tyres front P185/65R13 W2 option added; air box clarified as-delivered; SRF3 restrictor plate G301048 mandatory Jan 1 2022; P2 motorcycle engines up to 1005cc with 35mm restrictor, 2009+ stock 1075 lbs, 2008 stock 1025 lbs, modifie…
T2 Typo for BMW M2 CS Cup 2020 #31173suspension & brakes
T2 Request to Classify 2014 VW Jetta 1.8t TSI #30436cars added
SRF SADEV-SRF3 Transmission #30926cars addedaddedSRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive.
SRF SRF Update Maintenance, Repairs and Seals #30961wordingwordingSRF seal requirements clarified: seals now must be on driveline components in designated locations; unsealed components removed and inspected by CSR or Enterprises rather than engine shipped for testing.
T2 Request to add 2015 to Chevrolet Camaro SS/1LE 2010-2014 #29736other
SM Updates - Obsolete Parts & BOP Parts #30438wordingaddedSM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture.
T2 E92 BMW Spring Rate Request #30391suspension & brakes
T2 Please correct recent T2 Spec Line #30401suspension & brakes
Super Tour Mar 2021 ST21MAR192021-03-19
1:43.710Andrew Whitston · fastest of 7 · top 5 within 2.8s
1:43.747Donnie Isley · fastest of 7 · top 5 within 1.7s
108.0Zachary Whitston
1:41.798Danny Steyn · fastest of 68 · top 5 within 0.7s
1:42.564Preston Pardus · fastest of 67 · top 5 within 0.2s
113.6Marc Cefalo
-1.183squal -1.912s
98.9%qual 98.2%
1:34.790Tim Kezman · fastest of 10 · top 5 within 2.1s
1:34.689Tim Kezman · fastest of 10 · top 5 within 0.9s
143.3Aaron Kaplan
-9.058squal -8.920s
91.3%qual 91.4%
94 earlier rule changes on record, in force before Super Tour Mar 2021 (from 2019)17 suspension & brakes · 16 weight · 13 cars added · 11 tyres & wheels · 3 aero · 3 induction · 1 engine · 18 wording · 12 other · SRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement. · SRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified. · 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. · SM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure. · FV now permits 4 bolt wheels in addition to existing specifications. · FV now allows 4-bolt pattern wheels in addition to existing specifications. · T1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only. · SRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020. · T2 BMW E92 M3 08-14 adds AP Racing brake kit front 13.01.10038, rear 13.01.10053 to allowed list. · T2 Corvette C5 Z06 weight drops 50 lbs to 3175 with 45mm restrictor, 50 lbs to 3350 with 55mm. · T3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs. · FV rain tyre changes to Hoosier #44266 22.5 x 5.0 x 15 WET or W3. · FV allows non-spec Hoosier tyres at Regional races only; Majors, Super Tour, and Runoffs require spec tyres from 1/1/2020. · Formula Vee now allows 22.5 x 5.5 x 15 rear tires on front axle; rain tire mandated as Hoosier #44266 22.5 x 5.0 x 15 from 1/1/2020. · T2 must have fire system installed; T3 and T4 may have one per GCR 9.3. · T3 Ford Mustang EcoBoost gains three transmission gear ratio options. · T2 Chevrolet Camaro SS 10-14 adds 1LE-SS Track Pack with dry sump, suspension and brake options permitted. · T2 Camaro SS/1LE (10-14) permits 1LE-SS Track Pack, specific suspension, brake, dry sump, and driveshaft parts. · SRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024. · FV wheels may now be 15-inch 4.5J steel VW with same 5-bolt pattern as standard 4J, within track limits. · SRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers. · SRF front nose weight minimum reduced from 35 to 32 lbs. · SRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points. · FV exhaust exit opening repositioned: minimum one inch, maximum four inches behind rear body. · FV allows fifteen-inch steel wheels at 4J or 4.5J width, standard VW sedan or within track dimensions. · T2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove. · SRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102. · T2 Cadillac CTS-V classification expanded from 2006-07 model years to include 2004-05 models. · T2 Cadillac CTS-V 06-07 gains allowance for Hotchkiss sway bars up to 36mm front, 25mm rear. · T2 Cadillac CTS-V 06-07 requires 57mm flat plate restrictor. · T2 Ford Mustang GT 5.0L tire width reduced from 315 to 295. · FV exhaust outlet opening max distance from body rear increased from 3 to 4 inches. · T2 Audi TT RS 2018+ gains front sway bar to 30mm, rear to 28mm, springs to 1200 lb/in, aftermarket intercooler. · T2 Honda Civic Type-R 2017+ minimum weight rises 150 lbs to 3050, TIR turbo restrictor enlarges 38mm to 50mm. · FV front track maximum 52.500 inches; rear track 49.125–50.750 inches; spacers now allowed. · FV disc brake assembly minimum weight clarified to 16.5 lbs total; caliper minimum weight requirement of 1.65 lbs removed. · T2 Mustang GT rear anti-roll bar may now be removed or disconnected. · SM fuel pump and filter now permitted as Mazda or OEM equivalent part. · T1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017. · T2 Audi TT RS (2018-) newly classified: 2480cc, 3400 lbs minimum, 19-inch wheels, 275 tires, 371/310mm brakes, 40mm TIR required. · T2 2017+ Civic Type R sway bar rules relaxed: any front/rear up to 30mm allowed, specific HPD parts no longer required. · T4 and T3 Mazda MX-5 hardtop rules clarified: any OEM or aftermarket top permitted if retaining OEM silhouette; specific part numbers listed. · T2, T3, T4 now allow any thermostat serving original equipment intent only. · T2 Ford Mustang Boss 302 (12-13) minimum weight drops to 3500 lbs. · T2 Corvette C6 Coupe/Grand Sport 05-13 front camber maximum 3.0 degrees removed. · T2 Pontiac Firebird and Chevrolet Camaro SS 98-02 permit spring relocation to shock. · T3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years. · Ford Mustang GT 5.0L 2018+ classified in T2 at 3600 lbs minimum with 50mm restrictor, 19×11 wheels, 315 tyres, specific Ford Performance parts permitted. · FV intake manifold horizontal tube measurement location clarified; removed specific distance ranges from rule text. · 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. · T4 Celica GT wheelbase 2600 and 15x7 wheels added; Forte years narrowed; Fiesta ST starts 2014; Fiat 124 years 16-18 added; battery rule clarified. · T2 Porsche Cayman S/GTS years extended from 13-14 to 13-15, adding 2015 GTS model. · T2 Honda Civic Type-R 2017- allowed Cuztom Tuning FG-CIV16-V3-TR-BK alternate grill. · T1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications. · T2–T4 subframe bushings now permitted to be replaced with non-spherical bushings of any material.showhide
SRF Mandatory identification: #30223wordingwordingSRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement.
T2 Request BMW M2CS door glass removal #30254other
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.
T2 Request to Clarify New 2-piece Brake Rotor Rule #29106suspension & brakes
T2 please consider BoP for the following cars in T2 #29266weight -50 lbs
T2 Request clarification on most recent approval by the Board #29284suspension & brakes
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.
T2 Request to correct GCR for 2018+ FORD Mustang GT & Ecoboost #28803wording
FV Support for Recommended Item - 4 bolt wheels in FV #29084cars addedaddedFV now permits 4 bolt wheels in addition to existing specifications.
FV Support for 4-bolt pattern wheels #28955 #29118tyres & wheelsadded · tyres & wheelsFV now allows 4-bolt pattern wheels in addition to existing specifications.
T2 Request to Add a Vehicle to the Roster (contd.) #27698other
T2 Request brake upgrade and electric power steering pump #28946suspension & brakes
T2 Request to Classify 2004 Mercedes Benz 320 CLK #27663cars added
T2 Consider coil spring conversion Corvette in T2 #28824suspension & brakesadded · suspension & brakesT1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only.
SRF SRF Bump Stop Correction #27019wordingwordingSRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020.
T2 Please Add the Following BBK to Allowed List for E92 M3 #28421suspension & brakesadded · suspension & brakesT2 BMW E92 M3 08-14 adds AP Racing brake kit front 13.01.10038, rear 13.01.10053 to allowed list.
T2 C5 Weight Adjustment #28433weight -50 lbsfaster · weightT2 Corvette C5 Z06 weight drops 50 lbs to 3175 with 45mm restrictor, 50 lbs to 3350 with 55mm.
T2 Z3M Roadster Weight #28437weightfaster · weightT3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs.
FV FV Allow non-spec tire in Regional competition #26284tyres & wheelsadded · tyres & wheelsFV allows non-spec Hoosier tyres at Regional races only; Majors, Super Tour, and Runoffs require spec tyres from 1/1/2020.
FV Request to Allow Rear Tires on the Front of Formula Vee #26537tyres & wheelsadded · tyres & wheelsFormula Vee now allows 22.5 x 5.5 x 15 rear tires on front axle; rain tire mandated as Hoosier #44266 22.5 x 5.0 x 15 from 1/1/2020.
T2 Clarification of On-Board Fire System for T2 #27183wordingwordingT2 must have fire system installed; T3 and T4 may have one per GCR 9.3.
T2 Mustang Ecoboost and GT Transmission #27439cars addedaddedT3 Ford Mustang EcoBoost gains three transmission gear ratio options.
T2 Request for Dailey Engineering Dry Sump on 2010 Camaro SS #27514cars addedaddedT2 Chevrolet Camaro SS 10-14 adds 1LE-SS Track Pack with dry sump, suspension and brake options permitted.
T2 Request for Half Shafts - 2014 Camaro SS 1LE #27584otheraddedT2 Camaro SS/1LE (10-14) permits 1LE-SS Track Pack, specific suspension, brake, dry sump, and driveshaft parts.
T2 Request for Parity Among Vehicles #27665weight -50 lbs
T2 Request for 2016-2020 Camaro SS Help #27776weight -50 lbs
T2 Request for Competitive Adjustments to Honda Civic Type R #27839weight -50 lbs
T2 Request to add Toyota 86 GT to Spec Line #27910other
SRF SRF Rain / Brake Rule - BoD approved as follows #34958wordingwordingSRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024.
FV Clarification on Wheel Bolt Pattern #27603tyres & wheelsadded · tyres & wheelsFV wheels may now be 15-inch 4.5J steel VW with same 5-bolt pattern as standard 4J, within track limits.
SRF SRF Tire Warmer Rule #27622tyres & wheelstyres & wheelsSRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers.
SRF SRF / SRF3 Nose Weight Reduction #27706weightfaster · weightSRF front nose weight minimum reduced from 35 to 32 lbs.
SRF SRF / SRF3 Majors & Regional Class Updates #27723wordingwordingSRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points.
FV Allowed Modifications E&O #27398wordingwordingFV exhaust exit opening repositioned: minimum one inch, maximum four inches behind rear body.
FV E&O Wheels #27230tyres & wheelsadded · tyres & wheelsFV allows fifteen-inch steel wheels at 4J or 4.5J width, standard VW sedan or within track dimensions.
T2 Request spare tire/wheel clarification #27012wordingfasterT2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove.
SRF SRF Dash Windscreen Kit #27028aeroadded · aeroSRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102.
T2 Request to change Cadillac CTS-V years from 06-07 to 04-07 #26842cars addedaddedT2 Cadillac CTS-V classification expanded from 2006-07 model years to include 2004-05 models.
T2 Request to allow Hotchkiss front / rear sway bars on T2 CTS-V #26845suspension & brakesadded · suspension & brakesT2 Cadillac CTS-V 06-07 gains allowance for Hotchkiss sway bars up to 36mm front, 25mm rear.
T2 Correct T2 Mustang tire size #27024tyres & wheelsslower · tyres & wheelsT2 Ford Mustang GT 5.0L tire width reduced from 315 to 295.
FV Exhaust termination rule E&O #26702wordingwordingFV exhaust outlet opening max distance from body rear increased from 3 to 4 inches.
T2 2018+ Audi TT RS Suspension Allowances #26631suspension & brakesadded · suspension & brakesT2 Audi TT RS 2018+ gains front sway bar to 30mm, rear to 28mm, springs to 1200 lb/in, aftermarket intercooler.
T2 Request BOP adjustment for 2018 Honda Civic Type R-TIR removal #26882weight +150 lbsfaster · weightT2 Honda Civic Type-R 2017+ minimum weight rises 150 lbs to 3050, TIR turbo restrictor enlarges 38mm to 50mm.
FV E&O Dimensions #26674suspension & brakessuspension & brakesFV front track maximum 52.500 inches; rear track 49.125–50.750 inches; spacers now allowed.
T2 Request for Removal of Rear Anti-roll Bar in T2 Mustang GT #26533suspension & brakesfaster · suspension & brakesT2 Mustang GT rear anti-roll bar may now be removed or disconnected.
SM Request to allow aftermarket fuel filters. #26370otheraddedSM fuel pump and filter now permitted as Mazda or OEM equivalent part.
T2 Request Mustang GT Limited Prep 2018 Classification #24431cars addedaddedT1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017.
T2 Request to Classify 2018 Audi TT RS #25961cars addedaddedT2 Audi TT RS (2018-) newly classified: 2480cc, 3400 lbs minimum, 19-inch wheels, 275 tires, 371/310mm brakes, 40mm TIR required.
T2 Request for Adjustments on 2017+ Civic Type R #25969suspension & brakessuspension & brakesT2 2017+ Civic Type R sway bar rules relaxed: any front/rear up to 30mm allowed, specific HPD parts no longer required.
T2 Correct Mazda MX-5 Hard Top Notes #26137wordingwordingT4 and T3 Mazda MX-5 hardtop rules clarified: any OEM or aftermarket top permitted if retaining OEM silhouette; specific part numbers listed.
T2 Consider opening class rules to allow any thermostat #26187engineadded · engineT2, T3, T4 now allow any thermostat serving original equipment intent only.
T2 Ford Mustang Boss 302 (12-13) - correct weight #26287weight -50 lbsfaster · weightT2 Ford Mustang Boss 302 (12-13) minimum weight drops to 3500 lbs.
T2 Request camber correction 005-2013 corvette C6 #26288suspension & brakesremoved · suspension & brakesT2 Corvette C6 Coupe/Grand Sport 05-13 front camber maximum 3.0 degrees removed.
T2 Request 98-02 Firebird 98-02 Camaro reloacte rear spring #26291suspension & brakesadded · suspension & brakesT2 Pontiac Firebird and Chevrolet Camaro SS 98-02 permit spring relocation to shock.
T2 Cap 2016 Mazda Miata year at 2018 #26388cars addedremoved · cars addedT3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years.
T2 Class Ford Mustang GT 2018+ (reference letter 24431) #26400cars addedaddedFord Mustang GT 5.0L 2018+ classified in T2 at 3600 lbs minimum with 50mm restrictor, 19×11 wheels, 315 tyres, specific Ford Performance parts permitted.
FV FV Intake Manifold Clarification #26008wordingwordingFV intake manifold horizontal tube measurement location clarified; removed specific distance ranges from rule text.
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.
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.
SM Strike Tire Tread Language #26123wordingremovedSM tire tread protrusion language removed from GCR 9.1.7.C.5.
T2 Errors, Omissions, and Updates (Various) #22414wordingwordingT4 Celica GT wheelbase 2600 and 15x7 wheels added; Forte years narrowed; Fiesta ST starts 2014; Fiat 124 years 16-18 added; battery rule clarified.
T2 Request to classify 2015 Cayman GTS 3.4L in T2 #25335cars addedaddedT2 Porsche Cayman S/GTS years extended from 13-14 to 13-15, adding 2015 GTS model.
T2 Request for 2017-2018 Honda Civic Type R - 4 BOP Grill #25513aeroadded · aeroT2 Honda Civic Type-R 2017- allowed Cuztom Tuning FG-CIV16-V3-TR-BK alternate grill.
T2 Add Clarification to Spec Car Classifications Vehicle Spec #25774wordingwordingT1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications.
T2 Clarify Subframe Bushings Permitted for T2-T4 #25800suspension & brakesadded · suspension & brakesT2–T4 subframe bushings now permitted to be replaced with non-spherical bushings of any material.
About this data
Best is the class's fastest lap in that event's qualifying or race sessions, with the driver who set it, how many cars set a time that session and how close the top five were; a best from fewer than three cars is greyed. With two or more classes, "vs" is the gap of each class's best to the first class's at the same event. "% of FV" is the class's best as a share of FV's best at the same event (100% is level, less is quicker): weather and track condition move every class together, so this compares across years where the raw times do not. It still breaks when FV's own field changes or one session was wet and another dry. Newest event first. The coloured figure under each value is the change from the previous event that has one (green is quicker, red slower). Whole laps only, so events with different sector layouts still compare. Weather and track condition are not accounted for.