Lap times across years say as much about the weather as the class. % of T4 is each class's best lap as a share of T4'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.
Quickest here:T4 1:38.813 Jonathan Yanca, Runoffs 2016 qualifying · FM 1:26.043 Jacob Loomis, Runoffs 2016 qualifying · SM 1:40.514 Justin Hille, Runoffs 2016 qualifying · GTL 1:35.377 Wilson Wright, Runoffs 2016 qualifying
T4FMSMGTLsolid race · dashed qualifying · slower is lower
T4FMSMGTLsolid race · dashed qualifying · each class's best lap as a share of T4's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
2:35.876Matt Spicuzzi · fastest of 12 · top 5 within 2.4s+2.920s (+1.91%)
2:35.757Matt Spicuzzi · fastest of 12 · top 5 within 2.7s+3.124s (+2.05%)
127.6Matt Spicuzzi-6.0 mph (-4.5%)
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%)
+6.968squal +6.297s
104.5%qual 104.0%
29 rule changes (T4: 26, SM: 2, GTL: 1)6 cars added · 4 suspension & brakes · 4 weight · 3 induction · 2 removed · 2 tyres & wheels · 2 wording · 6 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. · T2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously only spherical bearings permitted. · T2, T3, T4 now allow under-dash electronics relocation for access after roll cage installation. · T4 Performance clarified: 1-piece alternative rotors permitted only at sizes listed in spec line; alternate brake kits may use matching 1-piece rotors. · T3 and T4 Mazda MX-5 Miata add permitted gearset kit PT#0000-02-6100 to Notes. · T4 MX-5 Miata 19-24 and 16-18, T3 MX-5 16-18 and Global Cup ND1/ND: discontinued DG Motorsports hardtop part #0000-07-5901 removed from permitted list.showhide
T4 02-06 R53 Mini Cooper Hotchkins Rear Camber Arms #40677suspension & brakes
T4 Allow Alt Bushing Material in Toe Links #39607suspension & brakesadded · suspension & brakesT2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously only spherical bearings permitted.
T4 Alternate Placement of Fuse Panel and Electronics Request #39370otheraddedT2, T3, T4 now allow under-dash electronics relocation for access after roll cage installation.
T4 Clarify T4 Brake Rotor Allowance #39503wordingwordingT4 Performance clarified: 1-piece alternative rotors permitted only at sizes listed in spec line; alternate brake kits may use matching 1-piece rotors.
T4 ND Spec Lines Wrong PT#'s #39170removedremovedT4 MX-5 Miata 19-24 and 16-18, T3 MX-5 16-18 and Global Cup ND1/ND: discontinued DG Motorsports hardtop part #0000-07-5901 removed from permitted list.
2:32.956Matt Spicuzzi · fastest of 10 · top 5 within 3.8s-1.474s (-0.95%)
2:32.633Alex Lozano · fastest of 10 · top 5 within 4.3s-1.575s (-1.02%)
133.7Alex Lozano+4.4 mph (+3.4%)
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%)
+11.797squal +10.155s
107.7%qual 106.6%
36 rule changes (T4: 29, SM: 4, GTL: 3)6 weight · 5 cars added · 4 tyres & wheels · 3 engine · 1 aero · 1 removed · 8 wording · 8 other · T2, T3, T4 spec table header changed from T2 to ET. · 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. · Ford SCCA Club Spec Mustang added to T3 at 3350 lbs; Mazda SCCA Club Spec MX-5 added to T4 at 2500 lbs. · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit. · T2, T3, T4: nine, nine, and thirty-seven expired spec lines removed effective 2025-01-01. · 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. · T2, T3 Mustang spec lines remove redundant driveshaft allowance notes across six model year ranges. · T2, T3, T4 fuel cell installations may omit charcoal canisters, emissions valves, and sensors. · T2, T3, T4 brake specifications clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter. · T2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors. · Porsche Spec Boxster moves to T4, minimum weight 2750 lbs, ineligible for Runoffs until 3 Super Tour events. · T4 BMW 320i Spec Line: Turner Motorsports intercooler #024703TMS02 now allowed. · 2005 Cadillac CTS 3.6L 6-speed manual classified in T3 Spec. · 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
T4 Incorrect Touring Heading #38451wordingwordingT2, T3, T4 spec table header changed from T2 to ET.
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.
T4 Correct Ring and Pinion Ratio to T3, Sorry I Mean T4 3.7 V6 Stang #38041wording
T4 Request to Classify Club Spec in Appropriate Touring Classes #37523cars addedaddedFord SCCA Club Spec Mustang added to T3 at 3350 lbs; Mazda SCCA Club Spec MX-5 added to T4 at 2500 lbs.
GTL Correct language regarding OEM Areo Devices #37137wordingwordingTA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit.
T4 Remove spec lines that have expired #37269removedremovedT2, T3, T4: nine, nine, and thirty-seven expired spec lines removed effective 2025-01-01.
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.
T4 Redundant Verbiage Regarding Mustang Spec Lines for Driveshaft #36484wordingwordingT2, T3 Mustang spec lines remove redundant driveshaft allowance notes across six model year ranges.
T4 R53 Mini Cooper S Weight Reduction Request #36612weight
T4 Move Spec Boxster to T4 #37158cars addedaddedPorsche Spec Boxster moves to T4, minimum weight 2750 lbs, ineligible for Runoffs until 3 Super Tour events.
GTL G16E-GTS Fuel Injection Spec Line Change #36588engineadded · engineGTL Toyota G16E-GTS removes direct injection prohibition, allowing direct injection engines.
GTL GTL Alternate Weight and Choke Option for L16 engine #36653engineadded · engineGTL L16 limited prep gains 32mm choke option at 1910 lbs, compression capped 12.0:1, valve lift .450 max.
2:34.430Matt Spicuzzi · fastest of 15 · top 5 within 1.8s-2.973s (-1.89%)
2:34.208Alex Lozano · fastest of 14 · top 5 within 2.2s-3.673s (-2.33%)
129.3Alex Lozano-0.9 mph (-0.7%)
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%)
+7.278squal +6.676s
104.7%qual 104.3%
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%)
-3.364squal -3.572s
97.8%qual 97.7%
48 rule changes (T4: 28, SM: 4, GTL: 16)11 weight · 10 cars added · 5 engine · 5 suspension & brakes · 3 aero · 2 induction · 1 removed · 6 wording · 5 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. · T2 Mustang GT 5.0L 15-17 and 2018- now permit Track/Performance Package parts; T3 V6 15-17 clarified to allow Track/Performance package. · T2-T4 Ford Mustangs: remove 25 lb penalty for non-OEM driveshaft, clarify alternate driveshaft allowance. · Audi S4 (2000–2002) classified in T3 with 2671cc, 3400 lbs minimum weight, 38mm restrictor, allowing 800lb springs and intercooler. · 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. · T3 and T4 Mazda RX-8 may remove or disable factory oil injection system. · T2, T3, T4 driveshafts may use carbon fiber, aluminum, or steel; two-piece replaced with one-piece; non-OEM adds 25 lbs. · T2, T3, T4 Spec Lines remove wheelbase requirement, add Required Restrictor specification. · T2 and T3 Nissan 370Z front brake rotors increase to 355×32 mm, rears to 350×20 mm. · 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. · T2, T3, T4 battery replacement no longer allows alternate manufacturer batteries within 10% OEM weight. · T4 now allows C-Spec touring cars to compete, in addition to existing B-Spec eligibility. · T2, T3, T4 spec lines expire 12/31/24; submit to appeal or cars are removed from class. · 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. · T3 Nissan 370Z now includes model years 2009–2022 with Nismo editions. · 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
GTL Request to Include Toyota GR86 in GTL #36324cars addedaddedGTL adds Toyota GR86 2021–2023, 2dr RWD, 101.3 in wheelbase.
GTL Inclusion of Modified Spec Miata for GTL competition #36325cars addedaddedGTL adds Spec Miata 1990–2005 with legal Spec Miata engine and intake system.
GTL Include Mazda MX5 RF 2017- in GTL #36428cars addedaddedGTL adds Mazda MX5 RF 2017- model with 91.0 in wheelbase.
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.
T4 B8/8.5 Audi S4 T3 and T2 #36195cars addedaddedAudi S4 (2000–2002) classified in T3 with 2671cc, 3400 lbs minimum weight, 38mm restrictor, allowing 800lb springs and intercooler.
T4 Allow OEM Front Spoiler 06-08 Miata in T4 #35941aero
T4 R53 Mini Cooper S spec line request In #36056suspension & brakes
GTL Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslower · weightGT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR.
GTL Allow 34 mm chokes for the Datsun 510 #35661induction +50 lbsfaster · inductionGTL Datsun 510 Limited Prep fuel induction increased to 34 mm chokes, minimum weight rises to 2000 lbs.
T4 Allow T4 and T3 RX8 to Disable/Remove Factory Oil Inj. #35761engineadded · engineT3 and T4 Mazda RX-8 may remove or disable factory oil injection system.
T4 2023 ND2 Miata Classification and Allowances #35837weight
T4 Errors and Omissions for 06-09 VW Rabbit Rotor #35851suspension & brakes
T4 Driveshafts #35916weightslower · weightT2, T3, T4 driveshafts may use carbon fiber, aluminum, or steel; two-piece replaced with one-piece; non-OEM adds 25 lbs.
T4 GCR ERROR - letter not properly applied to GCR #35999weight
T4 Allow any 400lb rear spring in the RX8 #35433suspension & brakes
T4 370Z Brake Rotor Size Correction #35487suspension & brakessuspension & brakesT2 and T3 Nissan 370Z front brake rotors increase to 355×32 mm, rears to 350×20 mm.
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.
GTL GT Direct Injection allowance and rules #35437engineadded · engineGT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment.
GTL GT2/3 remove Direction Injection not allowed in Spec line notes #35439engineadded · engineGT2 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E.
T4 More Car Lightening Stuff #35319wordingremovedT2, T3, T4 battery replacement no longer allows alternate manufacturer batteries within 10% OEM weight.
T4 Inclusion of B-C spec cars in T4 #35374cars addedaddedT4 now allows C-Spec touring cars to compete, in addition to existing B-Spec eligibility.
T4 T2-T4 Set expiration dates on spec lines #35378wordingremovedT2, T3, T4 spec lines expire 12/31/24; submit to appeal or cars are removed from class.
GTL Rotary Engine 12A Rotor Housings #35131engineadded · engineGTL 12A rotary engines may machine and use 13B housing to O.E. 12A spec across all port types.
GTL Request to Include Toyota GR86 in GTL #35198cars addedaddedGTL Toyota DR86 2021–2024 added to class.
GTL Errors and Omissions, GTL engines & Cars #35226wordingwordingGTL BMW Mini model years changed to 2002-2013.
T4 Mazda MX-5 ND1 Spec Line Request #34232weight +50 lbs
T4 BRZ/FRS/86 Spring Allowance #35038suspension & brakes
T4 Requested Update of Model Years of 370Z #35231cars addedaddedT3 Nissan 370Z now includes model years 2009–2022 with Nismo editions.
GTL Small Engines in GT Lite #34842weightfaster · weightGTL small unrestricted engines under 1399cc lose 38–79 lbs across Alfa, AMC, Triumph, Mini, Sprite, Fiat, Ford, Honda, Mazda, Nissan, Subaru, Toyota, Volkswagen.
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.
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.
GTL Weight for Nissan Sentra/200SX A 1400's #34918weight -50 lbsfaster · weightGTL Nissan Sentra/200SX A 1400 minimum weight reduced to 1800 lbs.
2:10.514Devin Anderson · fastest of 24 · top 5 within 0.5s+0.937s (+0.72%)
2:11.962Devin Anderson · fastest of 23 · top 5 within 0.1s-13.481s (-9.27%)
127.8Raymond Blethen+0.5 mph (+0.4%)
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%)
+4.267squal +4.472s
103.2%qual 103.4%
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%)
-0.685squal -0.950s
99.5%qual 99.3%
28 rule changes (T4: 20, SM: 1, GTL: 7)7 cars added · 7 weight · 4 suspension & brakes · 1 aero · 1 engine · 1 induction · 4 wording · 3 other · Mazda RX-8 T3 and T4 transmission and final drive pairing requirement removed; T4 gains Mazdaspeed radiator, spring kit, restrictor, spoiler, air dam. · T3 BMW 320i 14–15 gains aftermarket intercooler; T4 BMW 320i 14–15 loses it. · T3 and T2 Pontiac Solstice GXP 07-09 minimum ride height set to 3 inches. · 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. · T2 and T3 Mustang 11-14 may remove upper grille fog lights, replace with mesh or screen. · 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. · T5 touring class added; T2-T5 cars may race one class up; T5 maximum tyre width 225 with minimum aspect ratio 45. · T2-T5 Touring front and rear suspension maximum negative camber clarified to 3.5 degrees. · 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
T4 Inclusion of similar car. (CLK 320) #34626other
T4 Rules Clarification for Mazda RX8 Spec Line #34395wordingwordingMazda RX-8 T3 and T4 transmission and final drive pairing requirement removed; T4 gains Mazdaspeed radiator, spring kit, restrictor, spoiler, air dam.
T4 rule book corrections #34437otheraddedT3 BMW 320i 14–15 gains aftermarket intercooler; T4 BMW 320i 14–15 loses it.
T4 Ride Height Correction for the T3 Solstice. #34615suspension & brakessuspension & brakesT3 and T2 Pontiac Solstice GXP 07-09 minimum ride height set to 3 inches.
T4 2002-2006 Mini Cooper S R53 Spec Line Request #34336weight -50 lbs
T4 Mustang OEM Grill Request #33333aeroadded · aeroT2 and T3 Mustang 11-14 may remove upper grille fog lights, replace with mesh or screen.
T4 Mazda OEM LSD was letter 32655 typo #33666wording
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.
SM BOP for NB1 and NB2 #32309weightslower · weightSM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore.
T4 Allowable Springs and Sway Bars for 06-11 Civic si Spec Line #33294suspension & brakes
T4 Touring (T2-T5) Category #33617cars addedaddedT5 touring class added; T2-T5 cars may race one class up; T5 maximum tyre width 225 with minimum aspect ratio 45.
T4 ENO 9.1.9.2.D.1.e.1.a. #33651wordingwordingT2-T5 Touring front and rear suspension maximum negative camber clarified to 3.5 degrees.
GTL Fiat HP Limited Prep X1/9 Weight in GTL #33297weightslower · weightGTL Fiat X1/9 1500 Limited Prep minimum weight increases to 2000 lbs from 1835 lbs.
GTL GT2 (TA2)/GTA Part Number Update #33315wordingwordingGT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870.
GTL Request to add Ford Festiva to GTL #33335cars addedaddedGTL adds Ford Festiva 1988-1993 FWD hatchback with Mazda B3 1324cc engine.
2:09.577John Heinricy · fastest of 18 · top 5 within 0.7s-1.680s (-1.28%)
2:25.443John Heinricy · fastest of 18 · top 5 within 2.5s+14.484s (+11.06%)
127.4Nick Leverone-1.5 mph (-1.2%)
2:14.664Danny Steyn · fastest of 60 · top 5 within 0.2s+0.112s (+0.08%)
2:19.107Travis Wiley · fastest of 58 · top 5 within 0.9s+2.648s (+1.94%)
119.2Jonathan Neudorf-0.6 mph (-0.5%)
-6.336squal +5.087s
95.6%qual 103.9%
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%)
-4.263squal -1.788s
97.1%qual 98.6%
33 rule changes (T4: 29, SM: 1, GTL: 3)5 suspension & brakes · 5 tyres & wheels · 4 cars added · 4 weight · 2 engine · 1 aero · 1 induction · 1 removed · 5 wording · 5 other · GT1, GT2, GT3, GTL, GTX tail lights may now be original style or custom panel graphic with functioning red LED brake lamps. · T2-T4 Touring cars with alternative springs now permitted to use performance top hats with spherical bearings on shocks and struts. · SM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation. · T2-T4 touring cars model year 2018+ may use aftermarket ECU with 75 lb weight penalty via spec line adjustment. · Ginetta G40 added to GTL with Ford Zetec 1796cc engine, 2050 lbs minimum weight, 22.5mm SIR. · T2-T4 grill opening removal for cooling permitted without 16 square inch limit; mesh shape must match factory. · T2, T3, T4 clarify grill opening removal limited to 16 square inches for radiator cooling; mesh shape must be retained. · T2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted. · T2, T3, T4: clarified that 'permitted' or 'allowed' parts in spec lines are alternatives to category rule allowances, not replacements. · T4 adds 2014 VW Jetta 1.8T TSI to Spec Lines. · GT3 Volkswagen Fun Cup Beetle EVO3 classified, sealed SOHC 1984cc engine, 2060 lbs minimum weight.showhide
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.
T4 Request Wider Wheels for Hyundai Tiburon #32536tyres & wheels
T4 Request to Add Spec Line for 2004-2009 Mazda3 i 2.0 #32395weight
T4 Request Alternate Front & Rear Strut/Shock Top Hats #32452suspension & brakesadded · suspension & brakesT2-T4 Touring cars with alternative springs now permitted to use performance top hats with spherical bearings on shocks and struts.
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.
T4 Request to Allow the Use of Aftermarket ECU's in Touring #31067engineadded · engineT2-T4 touring cars model year 2018+ may use aftermarket ECU with 75 lb weight penalty via spec line adjustment.
T4 Request JWT BSR Kit for 02-06 Nissan Sentra SE-R/Spec V #31685other
T4 Please Confirm Touring 4 (98-00) BMW 323 is E46 generation #31972other
T4 RX-8 Spring Part Numbers (E&O) #32151suspension & brakes
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.
T4 Reply to letter #31486/29879 T2-T4 Grill openings #31935aerofaster · aeroT2-T4 grill opening removal for cooling permitted without 16 square inch limit; mesh shape must match factory.
T4 Request Allowances for 2005 - 2010 Mustang #31624wording
T4 Reply to letter 29879 T2-T4 Grill Openings #31486wordingwordingT2, T3, T4 clarify grill opening removal limited to 16 square inches for radiator cooling; mesh shape must be retained.
T4 Please Adjust 98-00 BMW 323 Min Weight to Reflect Current Class #31595weight -200 lbs
T4 Consolidate 12-13 and 14-15 Honda Civic Si spec lines for T4 #31596removed
T4 Request to clarify radiator hoses #31682otheraddedT2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted.
T4 Clarify Permitted/Allowed #31743wordingwordingT2, T3, T4: clarified that 'permitted' or 'allowed' parts in spec lines are alternatives to category rule allowances, not replacements.
1:54.397Stephen Blethen · fastest of 47 · top 5 within 0.9s-2.169s (-1.86%)
1:55.929John Heinricy · fastest of 46 · top 5 within 1.0s-0.994s (-0.85%)
127.3Alexander Schefer
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
+2.908squal +3.298s
102.5%qual 102.9%
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
-3.977squal -2.578s
96.6%qual 97.7%
29 rule changes (T4: 20, SM: 1, GTL: 8)7 cars added · 4 induction · 4 weight · 3 tyres & wheels · 1 aero · 1 suspension & brakes · 6 wording · 3 other · 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 · T3 Honda Civic Type-R 2020+ allowed brake rotor #45251-TGH-A01 with 25 lb penalty. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. · T2-T4 clutch discs and pressure plates must be at least 95% of factory OEM weight, bolted to unmodified stock flywheel. · 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. · Toyota Supra 2020- added to T2 with 2998 cc engine, 3450 lbs minimum weight, 19×10 wheels, 295 tyres. · 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. · T2 BMW M2 CS Cup 2020+ classified at 2979 cc, 3625 lbs, 295 tires, 10.5×18 wheels, 380/390 mm brakes. · T4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, plus 25 lb penalty. · T3 Scion FR-S/Toyota 86 and Subaru BRZ capped to 2021 model year; T4 models capped to 2021. · T3 Alfa Romeo 4C Launch Edition variant now allowed.showhide
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.
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.
GTL Request to Allow Hood Bulge on Nissan B13 Sentra #30504aeroadded · aeroGTL Nissan B13 Sentra may have hood bulge maximum 1.5 inches high by 10.0 long by 6.0 wide.
GTL Request BMW E21 Classing #30582otherunclearunclear
T4 Wrong Part Number on 320i Spec Line #30645wording
T4 Civic Type R Brake Rotors #29817weightslower · weightT3 Honda Civic Type-R 2020+ allowed brake rotor #45251-TGH-A01 with 25 lb penalty.
SM Updates - Obsolete Parts & BOP Parts #30438wordingaddedSM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture.
T4 Request consistency review in GCR #30263wordingwordingT2-T4 clutch discs and pressure plates must be at least 95% of factory OEM weight, bolted to unmodified stock flywheel.
GTL Request for Help for Mazda 12A #29754induction +50 lbsslower · inductionGTL Mazda 12A SIR increases to 29mm, minimum weight rises to 2000 lbs, 28mm SIR option with 175 lb penalty removed.
GTL Increase 13b SIR size #29867inductionfaster · inductionGTL Mazda 13B SIR increases from 26 mm to 28 mm; 27 mm option with 175 lbs removed.
T4 Request to Classify BMW M2 CS #29523cars addedaddedT2 BMW M2 CS Cup 2020+ classified at 2979 cc, 3625 lbs, 295 tires, 10.5×18 wheels, 380/390 mm brakes.
T4 Allow the SpecMX-5 Update Kit Into Touring 4 for the MX-5 #29681other
T4 Request Mustang 8.8†rear axle replacement #29860cars addedaddedT4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, plus 25 lb penalty.
T4 Cap year range on all 86s #29908wordingwordingT3 Scion FR-S/Toyota 86 and Subaru BRZ capped to 2021 model year; T4 models capped to 2021.
2:37.403John Heinricy · fastest of 20 · top 5 within 2.5s
2:37.881Chi Ho · fastest of 19 · top 5 within 1.6s
130.2Chi Ho
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
+5.867squal +4.806s
103.7%qual 103.1%
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
-6.280squal -5.460s
96.0%qual 96.5%
44 rule changes (T4: 25, SM: 2, GTL: 17)10 cars added · 6 suspension & brakes · 5 aero · 4 weight · 2 tyres & wheels · 1 engine · 1 induction · 11 wording · 4 other · 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. · 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. · Request to add vehicle to T2, T3, T4 roster; refer to letter #27663 in June 2020 Fastrack for decision. · GTL SIR stall test procedure clarified: system tested as raced, competitor must prevent air bypass behind restrictor. · 2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine, 17-inch wheels, 245 tyres, EIBACH PN# 2563.140 springs allowed. · GTL wing mount openings excluded from square inch area limit. · T3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs. · 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. · Pontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18x9.5, Sky weight drops to 3200 lbs. · Mazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01. · 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. · 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. · T3 and T4 Mazda RX-8 Base/R3 (04-12) reclassified to include Sport and GT variants. · Toyota 86 GT variant (2017–) added to T3 and T4 spec lines. · GTL Honda CRX 84-87 and 88-91 lose permission to use IRS with 2.5% weight penalty.showhide
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.
GTL GT Category Wording #29193wordingaddedGT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line.
GTL Request to change the Mazda 13b restrictor size #28518induction +175 lbsfaster · inductionGTL Mazda 13B restrictor increases from 24mm to 26mm SIR, minimum weight rises to 2125 lbs, alternative 27mm SIR option adds 175 lbs.
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.
T4 Scion FRS Solo Spec Coupe Gear Ratio #29021other
GTL Request to classify 1999-2007 Toyota MR2 Spyder body #28870cars addedaddedGTL: Toyota MR2 Spyder 1999–2007 newly classified for GTL competition.
GTL TA2 Gurney flap wicker clarification #28874wordingwordingTA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications.
GTL STO Gurney flap wicker clarification #28883wordingwordingSTO rear wing rules clarify that wicker is called Gurney flap in two places; no performance change.
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.
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.
T4 Request to Add a Vehicle to the Roster (contd.) #27698wordingunclearRequest to add vehicle to T2, T3, T4 roster; refer to letter #27663 in June 2020 Fastrack for decision.
GTL Stall Test #28709wordingwordingGTL SIR stall test procedure clarified: system tested as raced, competitor must prevent air bypass behind restrictor.
T4 Request to Classify 2004 Mercedes Benz 320 CLK #27663cars addedadded2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine, 17-inch wheels, 245 tyres, EIBACH PN# 2563.140 springs allowed.
GTL GTL Wing Rule #28754aeroadded · aeroGTL wing mount openings excluded from square inch area limit.
T4 Request to change allowed header part # for T4 06-15 Miata #28223wording
T4 Z3M Roadster Weight #28437weightfaster · weightT3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs.
GTL Wing Mounting Upright Size #27641aeroaeroGTL wing mounting posts limited to 85 square inches exposed area each, measured flat from side view.
GTL Wing Mounting Upright Size #27641aeroaeroGTL wing mounting posts limited to 85 square inches each, measured flat from side view.
GTL GTL wing end plates addition #28243aerofaster · aeroGTL wing endplates maximum area increased to 64 square inches from 8.5 by 3.0 inches rectangle.
GTL Clarification to letter #27406 #28309weight -50 lbsfaster · weightGTL Mazda 12A street port minimum weight drops to 1950 lbs.
T4 Request for 12-13 and 14-15 Honda Civic Springs #27848suspension & brakes
T4 Request to Clarify T4 05-10 Mustang Spring Allowance #27899suspension & brakes
GTL Windshield Clips #27323otheraddedGT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications.
T4 Request to Allow Brake Upgrade on T4 Mustang #27329suspension & brakes
T4 Please Switch the Solstice GXP as Specified in T2, to T3 #27413cars added -50 lbsfaster · cars addedPontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18x9.5, Sky weight drops to 3200 lbs.
T4 Request to Classify all Mazda RX8 Models in T3/T4 #27606cars addedaddedMazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01.
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.
GTL Request to Classify the MK1 two door Jetta #27648cars addedaddedGTL adds Jetta Mk1 two-door classification effective 2020-01-01.
T4 Clarification of On-Board Fire System for T2 #27183wordingwordingT2 must have fire system installed; T3 and T4 may have one per GCR 9.3.
T4 Mustang Ecoboost and GT Transmission #27439cars addedaddedT3 Ford Mustang EcoBoost gains three transmission gear ratio options.
T4 BRZ/FRS/86 Tire Size in T4 #27660tyres & wheels
2:11.257John Heinricy · fastest of 25 · top 5 within 0.2s
2:10.959Nick Leverone · fastest of 25 · top 5 within 0.6s
128.9Tommy Boileau
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
+4.857squal -16.133s
103.7%qual 87.7%
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
+5.500squal +3.295s
104.2%qual 102.5%
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
-3.122squal -4.260s
97.6%qual 96.8%
32 rule changes (T4: 15, SM: 4, GTL: 13)7 cars added · 4 engine · 3 suspension & brakes · 2 induction · 2 weight · 1 removed · 10 wording · 3 other · GTL Fun Cup Beetle engine weight set to 1850 lbs with Weber DMTL 32/34 induction. · T2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove. · 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. · 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. · T3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years. · 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. · 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. · 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
GTL Fun Cup Beetle #27334wordingwordingGTL Fun Cup Beetle engine weight set to 1850 lbs with Weber DMTL 32/34 induction.
T4 Request spare tire/wheel clarification #27012wordingfasterT2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove.
T4 Request to allow piggy back ECU on 2000 Mazda Protégé #26085engine
T4 Request helper spring as optional #26678suspension & brakes
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.
GTL Request GTX Fuel injection for previous GT-1 tube frame cars #26141engineadded · engineGTX tube frame cars now allowed fuel injection with maximum 90mm throttle body.
GTL Request to Classify Ligier JS2 R #26535cars addedaddedGTX adds Ligier JS2 R classification with restrictor and minimum weight.
GTL Request for GTL Mazda 13B SIR Increase with Penalty #26572engineadded · engineGTL Mazda 13B may use 25mm SIR with 175 lbs weight penalty added.
GTL Request Ride Height Clarification #26600wordingfasterGT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate.
T4 Request to classify 2000 - 2001 BMW 323 #25096cars added
GTL Request Mazda 12a Rotary SIR Increase #26081inductionadded · inductionGTL Mazda 12A may use 28mm SIR plus 175 lbs.
GTL Request to Classify Mustang 2 Body in GTL #26222cars addedaddedGTL: Ford Mustang 94-04 body newly classified for GTL racing.
SM Request to allow aftermarket fuel filters. #26370otheraddedSM fuel pump and filter now permitted as Mazda or OEM equivalent part.
T4 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.
T4 Consider opening class rules to allow any thermostat #26187engineadded · engineT2, T3, T4 now allow any thermostat serving original equipment intent only.
T4 Cap 2016 Mazda Miata year at 2018 #26388cars addedremoved · cars addedT3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years.
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.
T4 2012-2015 Honda Civic Si Performance Request #26129suspension & brakes
GTL Request for GTL Mini Adjustments #25754weightfaster · weightGTL 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 remove long inactive mini #25771removedremovedGTL BMC thru Rover Group removes four long inactive Mini engines: 948, 970, 1071, 1098.
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.
T4 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.
T4 Request for Adjustments to fiat 124 specline #25371induction
T4 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.
T4 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.
T4 Consider Solo SSC cross over classification into T4 #25802cars added
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 T4's best on the same day: the weather, the track and its configuration cancel out, so one figure compares across tracks and years where lap times cannot. It still moves when the yardstick's own balance changes or its field thins, and an event the yardstick did not run has no point. A best from fewer than three cars is greyed. The rule changes that took effect between two events are folded between their rows.