P2 vs SRF vs FM vs T2 pace at Michelin Raceway Road Atlanta
Quickest here:P2 1:22.533 Lucian Pancea, Super Tour Mar 2023 qualifying · T2 1:33.058 Raphael Assuncao, Super Tour Mar 2022 race
P2SRFFMT2solid race · dashed qualifying · slower is lower
P2SRFFMT2solid race · dashed qualifying · each class's best lap as a share of P2's at the same event (the reference class, changeable above); 100% is level, higher is quicker
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SRF
FM
T2
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Race best
Trap
Qual best
Race best
Trap
vs P2
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Qual best
Race best
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vs P2
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Super Tour Mar 2026 ST26MAR062026-03-06
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%)
31 rule changes (SRF: 4, T2: 27)6 weight · 5 induction · 4 cars added · 3 suspension & brakes · 3 tyres & wheels · 2 engine · 1 aero · 2 wording · 5 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. · 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.
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
1:33.885Raphael 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%)
41 rule changes (P2: 3, SRF: 6, T2: 32)6 suspension & brakes · 6 weight · 5 induction · 4 cars added · 4 tyres & wheels · 3 engine · 2 removed · 6 wording · 5 other · P2 2000 cc Pinto engine car minimum weight set to 1335 lbs. · 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. · 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. · P2 Spec Line E engine notes clarify oil system, ECU, and exhaust remain unrestricted; wording only. · P2 FIA Group CN notes clarify V de V European Proto Endurance Challenge bodywork, rear diffuser, wing, wheels, assisted shifting allowed; regulations link provided.showhide
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.
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.
P2 CN Spec ECU #35835wordingwordingP2 Spec Line E engine notes clarify oil system, ECU, and exhaust remain unrestricted; wording only.
P2 E&O - Correct FIA Group CN spec line notes #35900wordingwordingP2 FIA Group CN notes clarify V de V European Proto Endurance Challenge bodywork, rear diffuser, wing, wheels, assisted shifting allowed; regulations link provided.
T2 Allow T4 and T3 RX8 to Disable/Remove Factory Oil Inj. #35761engine
T2 Competition Adjustment Request/Wheel Size of E46 #35895tyres & wheels
T2 Brake Request for 2009 Porsche Cayman #35723suspension & brakes
Super Tour Mar 2024 ST24MAR082024-03-08
1:24.228Lucian Pancea · fastest of 4 · top 4 within 5.2s+1.695s (+2.05%)
1:26.233Sherman Chao · fastest of 4 · top 4 within 17.9s+2.429s (+2.90%)
134.0Lucian Pancea-12.5 mph (-8.5%)
1:36.675Michael Kamalian · fastest of 2+0.164s (+0.17%)
1:36.782Michael Kamalian · only car+0.876s (+0.91%)
129.0Michael Kamalian-12.6 mph (-8.9%)
+10.549squal +12.447s
112.2%qual 114.8%
42 rule changes (P2: 7, SRF: 6, T2: 29)10 weight · 8 suspension & brakes · 4 tyres & wheels · 3 engine · 3 induction · 7 wording · 7 other · P2 AMAC and related cars: clarified B.1 modified engine range to 2008 and older stock engines only, with 38mm restrictor and 1025 lbs minimum weight. · P2 Suzuki GSX-R1000 engine: 2007–2008 crankcase 11300-21860 may be replaced with 2016–2019 GSX-S1000 part 11301-04840. · SRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch. · SRF 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. · SRF adds mandatory front brake ducts 12–36 inches, throttle pedal heel-toe extension, braided stainless flex lines, camber limit 5.0 degrees, radiator opening height 3½ ± ½ inches, rear shift cable clamp P/N WM302007A. · P2 Table 1 engine date ranges clarified: Stock Engine replaced with specific marques Suzuki, Yamaha, Honda, BMW for 2009-newer and 2008-older rows. · SRF radiator options expanded: Enterprises P/N 480465 with baffle 480464, 480466, or Automotive 1R698 and CU698 allowed if cross-reference equivalent. · SRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance. · P2 minimum side body height must equal front axle centerline height, viewed from side. · P2 closed cockpit single seat cars now prohibited unless Table 1 spec line permits. · SRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13. · P2 engine table spec line B.1 redundant effective date language removed and table updated. · P2 motorcycle restrictor reduced 35mm to 34mm for 2011+ Kawasaki; minimum weights increased to 1100 lbs for 2009+ engines; cockpit length corrected to 23.622 inches.showhide
T2 T2-T4 Set expiration dates on spec lines #35378induction
T2 Reply to letter #35161 and #31661 #35384weight +75 lbs
P2 E&O - Clarify B.1 modified engine range in AMAC spec lines #35225wordingwordingP2 AMAC and related cars: clarified B.1 modified engine range to 2008 and older stock engines only, with 38mm restrictor and 1025 lbs minimum weight.
P2 Replacement Engine Crankcase for 07/08 Suzuki GSX-R1000 Engines #35340engineadded · engineP2 Suzuki GSX-R1000 engine: 2007–2008 crankcase 11300-21860 may be replaced with 2016–2019 GSX-S1000 part 11301-04840.
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 Requested Update of Model Years of 370Z #35231other
P2 Correct Table 1 for Engine Date Range Specifications #35182wordingwordingP2 Table 1 engine date ranges clarified: Stock Engine replaced with specific marques Suzuki, Yamaha, Honda, BMW for 2009-newer and 2008-older rows.
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.
P2 Clarify minimum side body height requirement #34143wordingwordingP2 minimum side body height must equal front axle centerline height, viewed from side.
P2 Clarify closed cockpit single seat car allowance #34144wordingwordingP2 closed cockpit single seat cars now prohibited unless Table 1 spec line permits.
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.
P2 Remove redundant effective date language and update engine table #34012wordingwordingP2 engine table spec line B.1 redundant effective date language removed and table updated.
P2 E&O - Correct dimensional equivalents #34038enginefaster · engineP2 motorcycle restrictor reduced 35mm to 34mm for 2011+ Kawasaki; minimum weights increased to 1100 lbs for 2009+ engines; cockpit length corrected to 23.622 inches.
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
1:22.533Lucian Pancea · fastest of 4 · top 4 within 4.2s-1.480s (-1.76%)
1:23.804Lucian Pancea · fastest of 4 · top 4 within 4.6s+0.733s (+0.88%)
146.5Lucian Pancea-3.5 mph (-2.4%)
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%)
+12.102squal +13.978s
114.4%qual 116.9%
25 rule changes (P2: 7, SRF: 3, T2: 15)3 cars added · 3 engine · 3 tyres & wheels · 2 suspension & brakes · 2 weight · 6 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. · Sebeco NP01-EVO and Elan NP01 added to P2 with Mazda 2.0L MZR, no restrictor required, 1600 lb minimum weight. · P2 Radical SR3/SR4, Cup, Club Sport, Pro-Sport, PR6: assisted shifting clarified from A-assisted to Aassisted; Cup engine restrictor changed from Unrestricted to Not required. · P2 chassis now allows composite materials partially installed; anti-intrusion panels attachment simplified; Stohr and converted models clarified. · 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. · P2 chassis construction clarified: full composite allowed; partial composite must roll without composite parts installed. · P2 classification wording cleaned up in GCR section 9.1.8.C and GCR contents. · P2 Oldsmobile cam rules correct spelling from 'after market' to 'aftermarket' in two sections.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
P2 Request to Classify Sebeco NP01 #33378cars addedaddedSebeco NP01-EVO and Elan NP01 added to P2 with Mazda 2.0L MZR, no restrictor required, 1600 lb minimum weight.
P2 Radical spec line clarifications #33485wordingwordingP2 Radical SR3/SR4, Cup, Club Sport, Pro-Sport, PR6: assisted shifting clarified from A-assisted to Aassisted; Cup engine restrictor changed from Unrestricted to Not required.
P2 E&O original class intent #33519wordingwordingP2 chassis now allows composite materials partially installed; anti-intrusion panels attachment simplified; Stohr and converted models clarified.
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
P2 E&O Clarification of Chassis Construction Requirements #32469wordingwordingP2 chassis construction clarified: full composite allowed; partial composite must roll without composite parts installed.
P2 Clean up P2 wording #32525wordingwordingP2 classification wording cleaned up in GCR section 9.1.8.C and GCR contents.
T2 Request Alternate Front & Rear Strut/Shock Top Hats #32452suspension & brakes
1:24.013Robert Iversen · fastest of 6 · top 5 within 3.1s-3.393s (-3.88%)
1:23.071Robert Iversen · fastest of 6 · top 5 within 4.0s-3.049s (-3.54%)
150.1Robert Iversen+13.2 mph (+9.6%)
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%)
+9.987squal +11.114s
112.0%qual 113.2%
45 rule changes (P2: 13, SRF: 5, T2: 27)7 suspension & brakes · 7 weight · 6 cars added · 3 engine · 1 induction · 1 tyres & wheels · 12 wording · 8 other · P2 adds Beasley B2 at 1350 lbs with Mazda 12A, 40.5mm venturi, and up to 16.5in wing chord. · P2 wings: terminology change from 'cord' to 'chord', and 'only' removed from Bobsy and Jondal notes. · P2 Converted F5 cars renamed F500, must retain F500 suspension, minimum width 55 inches. · P2 motorcycle engines gain 5cc to 1505cc max, two-stroke gains 5cc to 1205cc max, automotive engines add 50 lbs minimum weight to 1350 lbs. · P2 Control Area definition clarified: rectangular zone from rear edge of front tires to front edge of rear tires, full car width. · P2 Control Area definition clarified: rear tire edge and front tire edge bounds, car's lower surface width, floor extensions and aerodynamic attachments included, vertical structures prohibited. · 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… · P2 CN Honda K20A-FD2 engine rebuild clarified: balancing, porting, polishing prohibited; valve jobs and honing must follow factory procedures. · P2 Converted F5 cars must retain F5 suspension and meet P2 non-spec requirements except minimum width is 55 inches. · P2 minimum body width clarified: cannot extend inward beyond vertical plane through tire centerlines. · 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. · P2 tonneau covers now allowed to meet minimum dimensions; cockpit equipment attachment wording clarified. · P2 removes effective date 01/01/2021 from six car spec lines in Table 1. · P2 engine specs B.1, B.2, B.3 limited to maximum 4 valves per cylinder.showhide
P2 Add spec line for Beasley B2 #32147cars addedaddedP2 adds Beasley B2 at 1350 lbs with Mazda 12A, 40.5mm venturi, and up to 16.5in wing chord.
P2 E&O Table 1 spec line wing terminology #32148wordingwordingP2 wings: terminology change from 'cord' to 'chord', and 'only' removed from Bobsy and Jondal notes.
P2 E&O class name #32196wordingwordingP2 Converted F5 cars renamed F500, must retain F500 suspension, minimum width 55 inches.
T2 Reply to letter #31486/29879 T2-T4 Grill openings #31935suspension & brakes
P2 E&O letter #31539 – Control Area definition #31783wordingwordingP2 Control Area definition clarified: rectangular zone from rear edge of front tires to front edge of rear tires, full car width.
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
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 E92 BMW Spring Rate Request #30391suspension & brakes
T2 Please correct recent T2 Spec Line #30401suspension & brakes
Super Tour Mar 2021 ST21MAR192021-03-19
1:27.406Lucas Mann · fastest of 4 · top 4 within 5.9s
1:26.120Lucian Pancea · fastest of 3 · top 3 within 3.8s
136.9Lucian Pancea
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
+8.569squal +7.384s
110.0%qual 108.4%
93 earlier rule changes on record, in force before Super Tour Mar 2021 (from 2019)16 weight · 15 cars added · 15 suspension & brakes · 7 engine · 5 induction · 5 tyres & wheels · 4 aero · 15 wording · 11 other · P2 adds new spec line for 2-cycle 3-cylinder engine up to 820cc with 10 front, 14–15 rear wheel width. · SRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement. · P2 motorcycle-engine cars: 2009+ stock 37mm restrictor, 2008- stock 35mm, modified 1075 lbs. Honda K20A 50mm restrictor. Various spec cars: restrictors increased or decreased 0.5–3mm. · SRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified. · P2 rear wing rules clarified: standard wing 6×12 inches, end plates 14-inch square; alternate 1-meter formula wing 110cm wide, 9×18 inches, end plates 14×18 inches. · Elan NP01 added to P2 Table 1 as Spec Line car with 2000cc displacement and 42mm restrictor. · T1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only. · P2 Enterprises Sports Racer now permits 55mm flat plate intake restrictor Part # WM303013 as alternative to SIR. · 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. · P2 Enterprise Sports Racer 2.3L engine must use SIR or Flat Plate restrictor meeting peak horsepower, sized in whole or 0.5mm increments. · P2 electronic throttle control wording clarified: ETC permitted if stock ECU throttle pedal activates original throttle shaft mechanism. · P2 adds BMW to permitted motorcycle-based engines alongside Kawasaki, Suzuki, Yamaha, Honda. · 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. · 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. · P2 Honda K20A-FD2 non-composite chassis intake restrictor note clarified; restrictor implementation date removed. · P2 motorcycle engines: Stock restrictor to 35mm, Modified to 34mm; weights up to 1025 and 1125 lbs respectively. B.5 restrictor to 33mm, weight to 1185 lbs. · T2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove. · P2 cars limited to power application on maximum two wheels. · 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. · P2 Enterprise minimum weight increased to 1375 lbs.; peak horsepower of sealed ESR engine reduced per CRB specification. · 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. · T2 Mustang GT rear anti-roll bar may now be removed or disconnected. · P2 stock and modified engines get smaller restrictors (35.0mm, 34.0mm, 33.0mm) and heavier minimums (1025, 1125, 1185 lbs). · P2 Line A.1 restrictor reduced from 40mm to 38mm. · 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. · P2 Spec Line cars now allow 1345cc Hayabusa stock engines at 1050 lb minimum with 30mm restrictor. · P2 Group CN Honda K20A-FD2 55mm intake restrictor implementation delayed from 1 January to 3 March 2019. · P2 Honda K20A-FD2 Group CN must use stock intake manifold, 64mm throttle, 55mm restrictor at 1500 lbs minimum. · 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
P2 Add a new spec line for a 2-cycle, 3-cylinder engine up to 820cc #30272cars addedaddedP2 adds new spec line for 2-cycle 3-cylinder engine up to 820cc with 10 front, 14–15 rear wheel width.
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
P2 E&O clarification of P2 rear wing requirements #29205aeroaeroP2 rear wing rules clarified: standard wing 6×12 inches, end plates 14-inch square; alternate 1-meter formula wing 110cm wide, 9×18 inches, end plates 14×18 inches.
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
T2 Request to correct GCR for 2018+ FORD Mustang GT & Ecoboost #28803wording
T2 Request to Add a Vehicle to the Roster (contd.) #27698other
T2 Request brake upgrade and electric power steering pump #28946suspension & brakes
P2 Classify Elan NP01 in P2 Table 1 #28812cars addedaddedElan NP01 added to P2 Table 1 as Spec Line car with 2000cc displacement and 42mm restrictor.
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.
P2 SCCA Enterprises ESR / P2 engine restrictor testing #28669otheraddedP2 Enterprises Sports Racer now permits 55mm flat plate intake restrictor Part # WM303013 as alternative to SIR.
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.
P2 Add ESR inlet restrictor #27869inductionadded · inductionP2 Enterprise Sports Racer 2.3L engine must use SIR or Flat Plate restrictor meeting peak horsepower, sized in whole or 0.5mm increments.
P2 Request for addition of BMW Engine in P2 Engine Table #27821engineadded · engineP2 adds BMW to permitted motorcycle-based engines alongside Kawasaki, Suzuki, Yamaha, Honda.
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.
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.
P2 Update Engine Table Line E notes #27414wordingwordingP2 Honda K20A-FD2 non-composite chassis intake restrictor note clarified; restrictor implementation date removed.
P2 Update P2 Engine Table spec lines to reflect 3/1/2019 #27254engineslower · engineP2 motorcycle engines: Stock restrictor to 35mm, Modified to 34mm; weights up to 1025 and 1125 lbs respectively. B.5 restrictor to 33mm, weight to 1185 lbs.
T2 Request spare tire/wheel clarification #27012wordingfasterT2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove.
P2 E&O Transmissions #27006engineslower · engineP2 cars limited to power application on maximum two wheels.
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.
P2 Request to restrict all cars #26246weightslower · weightP2 Enterprise minimum weight increased to 1375 lbs.; peak horsepower of sealed ESR engine reduced per CRB specification.
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.
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.
P2 Change Engine Table Lines B.1 & B.5 #25777inductionslower · inductionP2 stock and modified engines get smaller restrictors (35.0mm, 34.0mm, 33.0mm) and heavier minimums (1025, 1125, 1185 lbs).
P2 Change Line A.1 restrictor size #26429engineslower · engineP2 Line A.1 restrictor reduced from 40mm to 38mm.
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.
P2 Request to Allow 1345cc Hayabusa Engines for Spec Line P2 Cars #25595cars addedaddedP2 Spec Line cars now allow 1345cc Hayabusa stock engines at 1050 lb minimum with 30mm restrictor.
P2 Change CN inlet restrictor implementation date #25816wordingwordingP2 Group CN Honda K20A-FD2 55mm intake restrictor implementation delayed from 1 January to 3 March 2019.
P2 Clarify Honda K20A-FD2 parts requirement #25950engineslower · engineP2 Honda K20A-FD2 Group CN must use stock intake manifold, 64mm throttle, 55mm restrictor at 1500 lbs minimum.
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.
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 P2" is the class's best as a share of P2'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 P2'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.