EP vs T3 vs SRF3 pace at Buttonwillow Raceway Park
Quickest here:EP 1:53.088 Glen McCready, Cal Club 2025 qualifying · T3 1:55.675 Scotty B White, Cal Club 2026 race · SRF3 1:50.233 Caleb Shrader, Cal Club 2025 qualifying
EPT3SRF3solid race · dashed qualifying · slower is lower
EPT3SRF3solid race · dashed qualifying · each class's best lap as a share of EP's at the same event (the reference class, changeable above); 100% is level, higher is quicker
Event
EP
T3
SRF3
Qual best
Race best
Trap
Qual best
Race best
Trap
vs EP
% of EP
Qual best
Race best
Trap
vs EP
% of EP
Cal Club 2026 CALCL262026-02-21
1:57.474Kurt Frietzsche · fastest of 4 · top 4 within 4.5s+4.386s (+3.88%)
1:57.999Kurt Frietzsche · fastest of 4 · top 4 within 4.9s+4.512s (+3.98%)
131.6Joe Carr+23.8 mph (+22.1%)
1:55.970Scotty B White · fastest of 4 · top 4 within 10.5s+0.005s (+0.00%)
1:55.675Scotty B White · fastest of 5 · top 5 within 12.1s-0.522s (-0.45%)
137.2Scotty B White+25.7 mph (+23.1%)
-2.324squal -1.504s
98.0%qual 98.7%
1:50.913Asad Nikadambaev · fastest of 27 · top 5 within 1.1s+0.680s (+0.62%)
1:52.070Asad Nikadambaev · fastest of 27 · top 5 within 0.8s+1.245s (+1.12%)
138.9Paul Marino+20.7 mph (+17.5%)
-5.929squal -6.561s
95.0%qual 94.4%
45 rule changes (EP: 23, T3: 18, SRF3: 4)12 weight · 3 induction · 3 tyres & wheels · 2 engine · 2 suspension & brakes · 1 cars added · 21 wording · 1 other · T3 Ford Mustang V6 Spec Line expands to include 2005-2010 chassis and body with 2011-2014 engine. · T3 Nissan 350Z DE Motor loses 25 lbs to 3100, HR Motor loses 25 lbs to 3250. · T2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously prohibited except in specified examples. · EP BMW 325i/is E30 throttle body specified as 60mm in fuel injection notes. · T3 Ford Spec Mustang restrictor opens to 45mm, weight drops to 3400 lbs. · T3 BMW Spec E9X tire width increases to 255 from 225; spec E9X tire or any DOT permitted. · T3 SpecE46 permitted tire width increases from 225 to 245. · T2, T3, T4 cars may relocate under-dash electronics and fuse boxes for access after roll cage installation. · T4 Performance now permits 1-piece alternative rotors matching spec line sizes; alternate brake kits allowed same. · EP Triumph TR2-TR4A allows 5-speed gearbox without overdrive; removes Weber carb and weight specification. · EP BMW Z3 2.5L restrictor reduced 52mm to 50mm, weight increased to 2550 lbs base; five other BMW models get smaller restrictors. · T3 Ford Mustang EcoBoost loses optional 2-piece 355mm Brembo rotor brake kit option with 50 lb penalty. · EP Nissan 280Z minimum weight reduced from 2560 to 2400 lbs. · EP Mazda MX-5 1.8L 90-97 weight reduced to 2125 lbs from 2150 lbs. · HP Austin-Healey Sprite/Midget 1098cc minimum weight drops 80 lbs to 1550. · HP Volvo 142/142E gains compression ratio limit 12.0:1 and valve lift limit .425". · HP Mini Cooper 07-15 valve lift reduced to .390", from .450". · FP and HP Volkswagen Rabbit descriptions updated: Convertible changed to Cabriolet in FP; Cabriolet added to three HP engine variants. · EP, FP, HP: rear drum brake to disc conversion clarified; rotors solid, diameter limited to largest front rotor permitted. · EP Ford Mustang (94-98) fuel injected throttle body inside diameter specified at 60. · T3 Honda S2000 wheels grow to 17x9.0 front and 17x10 rear; tyres widen to 255 front and 275 rear. · T3 and T4 Mazda MX-5 Miata models add approved gear kit PT#-0000-02-6100 to notes. · T4 Mazda MX-5 Miata/Club/RF (19-24) and (16-18) remove discontinued hardtop part #0000-07-5901; T3 MX-5 Miata (16-18) and Global Cup ND (16-21) same. · HP Plymouth Arrow transmission max speeds clarified to 4 or 5. · EP, FP, HP wheel diameter added to Appendix G as absolute maximum specification. · EP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only. · SRF3 adds HD Oil Cooler P/N G1148500 as alternative to standard cooler P/N G480503. · SRF3 brakes restructured: Hawk Blue 801993 pads, Wilwood 800065 rotors only; adds Girling 880358, Wilwood 880357, Tilton 880360 master cylinders. · T2, T3, T4 Spec Lines table header changed from T2 to ET. · EP BMW Z4 03-05 restricted to 52mm flat plate intake restrictor. · EP Fiat 124 Spider 1600 & 2000 weight drops 50 lbs to 2000; carburetors gain 2mm chokes to 36mm. · BMW Spec E46 in T3 updates to SpecE46 rules Version 3.0. · HP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines. · T3 Ford Mustang V6 15-17 weight drops 50 lbs to 3350, brake options clarified with M2300V now 50 lb penalty or Brembo alternative. · T3 BMW Spec E46 rules updated to Version 3.0 from Version 1.1. · Chevrolet Spark 16-22 classified HP Pre at 1850 lbs minimum weight, fuel injected, 1399 cc. · HP Ford Festiva 88-93 minimum weight drops to 1600 lbs, variants to 1640 and 1680 lbs; compression ratio raised to 11.0:1. · SRF drivers with disabilities may modify seat and controls for safety and comfort with approval and logbook notation. · SRF SADEV-SRF3 6-speed sequential transmission gear ratios wording clarified, effective 2025-04-01. · T3 BMW Spec E46 updates to SpecE46 rules Version 1.1 dated Jan. 6, 2025. · T3 Ford Mustang V6 11-14 minimum weight drops 25 lbs to 3325. · EP BMW Z3 and 3-series models get smaller intake restrictors: Z3 2.5L to 52mm, Z3 2.8L to 55mm, 328i to 58mm, 325i to 56mm. · EP, FP, HP: interior or exterior mirrors meeting rule 9.3.36 now permitted. · EP Honda S2000 1997cc base loses 75 lbs to 2375; 2157cc base loses 60 lbs to 2450. · EP Mazda MX-5/Miata 99-05 minimum weight drops to 2100 lbs, 2153 lbs with power adder, 2205 lbs with two adders.showhide
T3 Please change 2011-2014 Mustang V6 Spec Line to 2005-2014 #39558wordingneutralT3 Ford Mustang V6 Spec Line expands to include 2005-2010 chassis and body with 2011-2014 engine.
T3 Nissan 350Z Weight Request #39598weight -25 lbsfasterT3 Nissan 350Z DE Motor loses 25 lbs to 3100, HR Motor loses 25 lbs to 3250.
T3 Allow Alt Bushing Material in Toe Links #39607suspension & brakesfasterT2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously prohibited except in specified examples.
EP Request to Update E30 BMW Throttle Body Diameter Verbiage #39363wordingneutralEP BMW 325i/is E30 throttle body specified as 60mm in fuel injection notes.
T3 Request to Allow Spec Mustang to Touring 3 in Appendix M Trim #39196weight -50 lbsfasterT3 Ford Spec Mustang restrictor opens to 45mm, weight drops to 3400 lbs.
T3 Tire Help for Spec E9X in T3 #39222tyres & wheelsfasterT3 BMW Spec E9X tire width increases to 255 from 225; spec E9X tire or any DOT permitted.
T3 SpecE46 Tire Sizing #39292tyres & wheelsfasterT3 SpecE46 permitted tire width increases from 225 to 245.
T3 Alternate Placement of Fuse Panel and Electronics Request #39370wordingneutralT2, T3, T4 cars may relocate under-dash electronics and fuse boxes for access after roll cage installation.
T3 Clarify T4 Brake Rotor Allowance #39503suspension & brakesneutralT4 Performance now permits 1-piece alternative rotors matching spec line sizes; alternate brake kits allowed same.
EP TR2 Notes E&O #39180wordingunclearEP Triumph TR2-TR4A allows 5-speed gearbox without overdrive; removes Weber carb and weight specification.
EP Balance of Power #39187induction +50 lbsslowerEP BMW Z3 2.5L restrictor reduced 52mm to 50mm, weight increased to 2550 lbs base; five other BMW models get smaller restrictors.
T3 T3 Ecoboost Mustang clarification #39236wordingunclearT3 Ford Mustang EcoBoost loses optional 2-piece 355mm Brembo rotor brake kit option with 50 lb penalty.
EP Please Lower Weight of 280Z #38871weight -160 lbsfasterEP Nissan 280Z minimum weight reduced from 2560 to 2400 lbs.
EP Miata Weight Adjustment Follow Up #38949weight -25 lbsfasterEP Mazda MX-5 1.8L 90-97 weight reduced to 2125 lbs from 2150 lbs.
EP Weight Break for 1098 Midget / Sprite #38970weight -80 lbsfasterHP Austin-Healey Sprite/Midget 1098cc minimum weight drops 80 lbs to 1550.
EP HP Volvo 142 spec omission #38994engineslowerHP Volvo 142/142E gains compression ratio limit 12.0:1 and valve lift limit .425".
EP HP Mini DOHC 1.6 #38996engineslowerHP Mini Cooper 07-15 valve lift reduced to .390", from .450".
EP Add to Rabbit description #39019wordingneutralFP and HP Volkswagen Rabbit descriptions updated: Convertible changed to Cabriolet in FP; Cabriolet added to three HP engine variants.
EP Clean-up 9.1.5.E.7e #39025wordingneutralEP, FP, HP: rear drum brake to disc conversion clarified; rotors solid, diameter limited to largest front rotor permitted.
EP Add TB size to Ford Mustang (94-98) Spec Line #39130wordingneutralEP Ford Mustang (94-98) fuel injected throttle body inside diameter specified at 60.
T3 Make the S2000 Competitive Again #38470tyres & wheelsfasterT3 Honda S2000 wheels grow to 17x9.0 front and 17x10 rear; tyres widen to 255 front and 275 rear.
T3 ND Gearset Request for T4 #39166wordingneutralT3 and T4 Mazda MX-5 Miata models add approved gear kit PT#-0000-02-6100 to notes.
T3 ND Spec Lines Wrong PT#'s #39170wordingneutralT4 Mazda MX-5 Miata/Club/RF (19-24) and (16-18) remove discontinued hardtop part #0000-07-5901; T3 MX-5 Miata (16-18) and Global Cup ND (16-21) same.
EP HP Plymouth Arrow spec omission #38995wordingneutralHP Plymouth Arrow transmission max speeds clarified to 4 or 5.
EP Add Wheel Diameter to Appendix G #39008wordingneutralEP, FP, HP wheel diameter added to Appendix G as absolute maximum specification.
EP Add TB ID tolerance to general Prod rules #39009wordingneutralEP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only.
SRF3 Add HD Oil Cooler #38979otherneutralSRF3 adds HD Oil Cooler P/N G1148500 as alternative to standard cooler P/N G480503.
T3 Incorrect Touring Heading #38451wordingneutralT2, T3, T4 Spec Lines table header changed from T2 to ET.
EP BMW Z4 update #38490inductionslowerEP BMW Z4 03-05 restricted to 52mm flat plate intake restrictor.
EP EP Fiat 124 Spider Competition Adjustment Request #38498weight -50 lbsfasterEP Fiat 124 Spider 1600 & 2000 weight drops 50 lbs to 2000; carburetors gain 2mm chokes to 36mm.
T3 correct letter 37421 #38204wordingunclearBMW Spec E46 in T3 updates to SpecE46 rules Version 3.0.
EP Base Weight Adjustment for H-Production X1/9 Spec Lines #38255weight -50 lbsfasterHP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines.
T3 S550 Mustang #38061weight -50 lbsfasterT3 Ford Mustang V6 15-17 weight drops 50 lbs to 3350, brake options clarified with M2300V now 50 lb penalty or Brembo alternative.
T3 correct letter 37421 #38204wordingunclearT3 BMW Spec E46 rules updated to Version 3.0 from Version 1.1.
EP Request for Classification of Chevrolet Spark #37755cars addedneutralChevrolet Spark 16-22 classified HP Pre at 1850 lbs minimum weight, fuel injected, 1399 cc.
EP Request to Lower Ford Festiva Minimum Weight to 1600 LBS #37939weight -100 lbsfasterHP Ford Festiva 88-93 minimum weight drops to 1600 lbs, variants to 1640 and 1680 lbs; compression ratio raised to 11.0:1.
SRF3 Driver Safety & Comfort #37966wordingneutralSRF drivers with disabilities may modify seat and controls for safety and comfort with approval and logbook notation.
T3 SpecE46 Tire Change #37421wordingunclearT3 BMW Spec E46 updates to SpecE46 rules Version 1.1 dated Jan. 6, 2025.
T3 S197 Mustang V6 in T3 #37594weight -25 lbsfasterT3 Ford Mustang V6 11-14 minimum weight drops 25 lbs to 3325.
EP Request Competition Adjustment to BMW Z3 2.5L #37120inductionslowerEP BMW Z3 and 3-series models get smaller intake restrictors: Z3 2.5L to 52mm, Z3 2.8L to 55mm, 328i to 58mm, 325i to 56mm.
EP Interpretation of Production Rules on Mirrors #37235wordingneutralEP, FP, HP: interior or exterior mirrors meeting rule 9.3.36 now permitted.
EP Weight Reduction for Honda S2000 #37466weightfasterEP Honda S2000 1997cc base loses 75 lbs to 2375; 2157cc base loses 60 lbs to 2450.
EP Mazda 1999 Miata 1.8L #37488weight -50 lbsfasterEP Mazda MX-5/Miata 99-05 minimum weight drops to 2100 lbs, 2153 lbs with power adder, 2205 lbs with two adders.
Cal Club 2025 CALCL252025-02-22
1:53.088Glen McCready · fastest of 5 · top 5 within 10.6s
1:53.487Glen McCready · fastest of 5 · top 5 within 10.6s
107.8Joe Carr
1:55.965Roger Eagleton · fastest of 6 · top 5 within 5.4s
1:56.197Scotty B White · fastest of 6 · top 5 within 3.8s
111.5J. David Orem
+2.710squal +2.877s
102.4%qual 102.5%
1:50.233Caleb Shrader · fastest of 33 · top 5 within 0.4s
1:50.825Caleb Shrader · fastest of 32 · top 5 within 0.8s
118.2John Black
-2.662squal -2.855s
97.7%qual 97.5%
316 earlier rule changes on record, in force before Cal Club 2025 (from 2019)59 cars added · 48 weight · 23 suspension & brakes · 23 tyres & wheels · 21 induction · 10 engine · 6 aero · 2 removed · 119 wording · 5 other · EP BMW Z3 2.5L requires 52mm flat plate intake restrictor; Z3 2.8L 55mm; 328i/is E36 58mm; 328i/ci E46 58mm; 325i/is E46 56mm; 325i/is E36 56mm; 325is M-Technic 56mm. · T3 Nissan 350Z HR Engine FPR restrictor increases from 47mm to 49mm. · Ford SCCA Club Spec Mustang classified T3 at 3350 lbs with driver; Mazda SCCA Club Spec MX-5 classified T4 at 2500 lbs with driver. · EP BMW 325i/is E30 (84-91) weight reduced 50–52 lbs across three spec lines to 2150, 2204, 2258. · T2, T3, T4 remove nine, nine, and thirty-six expired spec lines respectively, effective 2025-01-01. · Ford Spec Mustang moves to T3 with 44mm bore restrictor, 275 max tire, 3450 lbs minimum weight. · T3 Ford Mustang V6 (11-14) and (15-17) now permit cold air intake. · EP Triumph GT6 switches to three Weber 40 DCOE carbs with 28mm chokes, weight rises 50 lbs to 1990. · T3 VW Golf R (12-13 and 15-18) 36mm TIR placement now allows OEM turbo inlet, removing 60mm distance limit from impeller. · T2 and T3 Mustang spec lines remove redundant driveshaft alternate/aluminum allowance wording. · T2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors. · T2, T3, T4 brake component wording clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter. · T2, T3, T4 fuel cell cars may remove charcoal canisters, emissions valves, and sensors. · T3 and T4 Mazda RX-8 and MX-5 permit transmission kit #0000-02-5700. · Porsche Spec Boxster moves to T4, minimum weight 2750 lbs, requires 3 Super Tour events before Runoffs eligibility. · T4 BMW 320i 14-15 Spec Line expires 12/31/24 removed; Turner Motorsports intercooler #024703TMS02 allowed. · Cadillac CTS 02-07 3.6L classified in T3. · T3 BMW 328i/330i (06-12) model name updated; BMW 320i (14-15) newly classified at 3050 lbs. · T3 Subaru WRX STI max model year extended to 21, max tire size increased to 275. · T3 Honda HPD Civic Si FE1 newly classified with 1498cc engine, 18x8 wheels, 245 tires, 2950 lbs minimum weight. · T3 Subaru WRX STI 03-07 drops 100 lbs to 3200; Legacy GT/Spec B 05-09 drops 150 lbs to 3200. · HP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1. · EP Mazda Miata front and rear track widths increased to 1516/1534 mm (59.7/60.4 in.) across all generations. · SRF3 air filter rule removes K&N RC-9160 option, leaving only P/N WM301020 allowed. · SRF brake rotor minimum thickness increases from 12.20mm to 13.25mm, Wilwood vented rotor P/N 800065. · SRF3 Hoosier logo placement changes from four decals to three decals in different locations. · SRF Hoosier decal requirement reduced from four decals in specific locations to three decals with simpler placement rules. · HP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in). · SRF wet tires: P185/60R13 H20/W2 option removed; P185/65R13 W2 front now required with P205/60R13 W2 rear. · T3 Honda Civic Si (2017-2021) restrictor removed, weight to 2950 lbs, Runoffs eligibility requires 3 Super Tour events. · T3 Subaru STI (15-20) and WRX STI (03-07) permitted to use OEM spec block #IAG-ENG-S550 and head studs. · Audi TT Coupe 08-14 classified in T3 with 36mm TIR restrictor, 1984cc, 3200 lbs minimum weight. · T3 Mazda MX5 Miata/Club/RF (19-24) newly classified at 2550 lbs, 17x8.5 wheels, 245 tyres, 280 mm brakes. · Ford Mustang GT 5.0L and V6 now permit Track/Performance Package parts in T2 and T3. · T2-T4 Ford Mustangs: remove 25 lbs penalty for non-OEM driveshaft, clarify alternate driveshaft allowances. · T3 Nissan 350Z DE engine now permits cold air intake. · Audi S4 (2000-2002) moves to T3 with 3400 lbs minimum weight, 38mm turbo inlet restrictor required. · T3 BMW Z4 3.0si expands to include 3.0i Roadster and Coupe (07-08); hardtop permitted with positive fasteners. · Nissan 300ZX 84-89 classified to EP at 2550 lbs minimum, 2960cc 6-cyl SOHC, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit. · Mazda RX-7 92-97 newly classified EP Prep Level 2 at 2200–2310 lbs with 13B 6-port rotary engine. · EP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains. · SRF3 alternator pulley minimum weight reduced from 12 oz to 11 oz. · T3 Mazda MX-5 Global Cup Miata ND1/ND2 tire size changes to 225 DOT specification. · T3 and T4 Mazda RX-8 may remove or disable factory oil injection system. · T2, T3, T4 driveshafts may use alternative materials or one-piece units; non-OEM adds 25 lbs. · Audi S4 00-02 in T3 must compete in 3 Super Tour events before Runoffs eligibility. · HP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve, Scirocco 1588. · T3 Spec Z 350Z rear wheel width increases to 10 inches; HR Engine restrictors change from 42mm to 44mm. · Audi S4 2000-2002 classified in T3 at 3400 lbs with 38mm turbo inlet restrictor required. · T2-T4 Spec Lines remove wheelbase requirement, replace with Required Restrictor specification. · T2 and T3 Nissan 370Z brake rotors enlarged: front 320x28 to 355x32mm, rear 320x16 to 350x20mm vented. · T3 Ford Mustang V6 (11-14) restrictor requirement removed; (15-17) brake penalty reduced to +50 lbs from +100 lbs. · T3 Nissan 350Z and 370Z now allow brake booster vacuum regulator, must not be in-car adjustable. · T3 Ford Mustang 4.6L restrictor holes increased from 40 mm to 45 mm. · T3 Mazda RX-8 Spec Line retention appeal directed to letter #35584 for ruling. · Mazda RX-8 04-12 expiration date removed; no longer expires 12/31/24. · T3 Subaru WRX (02-05) spec line expiration deadline removed; class now permanent. · HP Honda Civic 1.5 (88-91) weight reduced to 2175 lbs base, 2229 lbs with power adder, 2284 lbs with two. · T3 Golf R 15-18 max wheel width increases to 9 inches, max tire size to 255. · T2, T3, T4 battery replacement wording simplified; OEM weight tolerance requirement removed. · T3 Ford Mustang V6 (11-14) gains approved strut tower brace and sway bar kit options. · T3 Ford Mustang EcoBoost 2015- intake restrictor increases from 35mm to 36mm TIR. · T4 now permits C-Spec cars to compete alongside B-Spec cars. · T2-T4 spec lines for 46 cars expire 12/31/24; appeal required to continue. · EP BMW Z3 2.5L weight increases to 2500 lbs, 2563 lbs with turbo, 2625 lbs with supercharger. · EP Mazda MX-5 1.8L 1990-97 minimum weight drops to 2150 lbs; 1994-97 variants to 2000, 2050, 2100 lbs respectively. · EP Triumph GT6 dual 1.75" carbs weight drops to 1940 lbs; triple Weber 40 DCOE options consolidated. · EP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm. · EP Triumph TR8 dry sump allowance moved from carburetor line to notes section. · EP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs. · SRF rain/brake light now requires Super Bright LEDs Inc. P/N PT-STRB-R24 with specific connector and rain light switch. · SRF requires Super Bright LEDs P/N PT-STRB-R24 rain/brake light with strobing capability and specific wiring. · SRF adds brake duct and pedal extension rules, rear shift cable clamp option, camber limit to 5.0°, radiator opening height 3.5" ±0.5", and P2 engine restrictor changes. · T3 Pontiac Solstice GXP front brake rotor increases from 296 to 355 mm vented. · T3 Nissan 350Z DE motor loses 75 lbs to 3125; HR motor gains 47mm restrictors, up from 44mm. · T3 Nissan 370Z model years expanded to include NISMO Edition through 2022. · T3 2010 Mustang GT 4.6 now allows 2013-14 GT style front/rear fascia, hood, and associated assemblies. · T3 BMW SpecE46 minimum weight drops 50 lbs to 2850. · T3 Subaru STI (15-20) minimum weight increases 100 lbs to 3450; all three STI variants get larger turbo inlet restrictors. · EP Porsche 944/924S combines 2.5L and 2.7L variants with new weights: 2250–2415 lbs depending on engine and year. · EP Triumph GT6 minimum weight reduced to 1800 lbs. · T3 Porsche Cayman (09-12) and (13-16) gear and final drive ratios adjusted; 09-12 6-SPD final drive 3.88 to 3.875, PDK 3.909 to 3.250; 13-16 6-SPD final drive 3.89 unchanged, PDK 3.91 to 3.250. · T3 Volkswagen GTI 06-10 turbo inlet restrictor increases from 36mm to 37mm. · T3 Volkswagen Golf R permitted model years extended from 15-16 to 15-18. · T3 Volkswagen Golf R 15-16 now permits Verkline WAS-048 camber arms. · BMW Spec E9X classified in T3 at 2975 lbs, must conform to SpecE9X rules Version 2.10, tire max 225. · T3 VW Golf GTI and Golf R TIR location clarified to maximum 60mm from impeller. · SRF radiator rule clarified: P/N 480466 replaceable with Automotive P/N 1R698, CU698 or manufacturer equivalent with documentation. · EP Triumph TR8 78-81 removes alternate front hub allowance note; stock hubs now required. · EP Triumph GT6 carburetors change from SU or Stromberg to 1.5" Auto-type. · EP Triumph GT6 brakes may now use TR-6 standard or alternate calipers and discs. · 2012-2013 Volkswagen Golf R added to T3 as new entry with 1984cc engine, 3080 lbs DSG/3050 STD, 36mm turbo inlet restrictor. · T3 Mazda RX-8 removes transmission/final drive pairing requirement; T4 removes same requirement, adds Mazdaspeed radiator and coil spring kit. · T3 BMW 320i (14-15) gains aftermarket intercooler permission; T4 loses it. · T3 Nissan 350Z and 370Z maximum tire width increases from 245 to 255. · T3 Pontiac Solstice GXP minimum ride height set to 3 inches. · FP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44). · T3 Camaro V6 1LE and LT-I4 Turbo 1LE max wheel diameter increases from 18 to 20 inches. · T3 removes Toyota 2022-up GR Cup and 2022-up GR86 Cup entirely from Spec Lines. · EP Porsche 914-6 2.0L intake valves increase to 2.0 mm, exhaust valves corrected to 38.0 mm. · SRF Hoosier wet front tire updated to P/N 46100 P185/60R13 H20 or W2. · T3 Ford Mustang V6 (15-17) weight drops to 3400 lbs, brake penalties reduced to +100 lbs and +50 lbs. · BMW SpecE46 in T3 loses 50 lbs, to 2900. · T3 adds 2022 Toyota GR Cup and GR86 Cup, both 2387cc, 2700 lbs, 245/620R18 slicks, 332x32F/280x32R brakes. · SRF Hoosier front rain tyre part number changes from 46100 to 46101 P185/65R13 W2. · T3 BMW Spec E46 weight reduced 25 lbs, to 2925. · T3 BMW 323Ci/Is weight reduces to 2750 lbs from 3000 lbs. · T3 BMW SpecE46 must conform to SpecE46 rules Version 2.10, updated from 2.7. · EP BMW Z3 2.5L intake restrictor reduced from 58mm to 56mm flat plate. · T3 06-10 VW GTI, Jetta GLI allowed to use ECS Tuning performance alternative intercooler. · SRF Renault Alliance solid front rotors banned; restrictor reduced 35mm to 34mm for 2011+ Kawasaki; minimum weight increased to 1100 lbs for 2009+ stock engines. · SRF3 tail sections allowed on SRFs with GEN3 airbox shimming up to 19 mm; alternate dash panel P/N 180100 or 180101 relocated in rules. · T3 Porsche Spec Boxster tire rule updates to current SPB rules or any 245 DOT tire. · T3 06-10 VW GTI and Jetta permitted to use OEM VW knuckles 3C0407253F and 3C0407254F. · T3 BMW 320I now permitted to use aftermarket intercooler. · Porsche Cayman (13-16) classified in T3 at 3225 lbs with 2700cc engine, 18x9 wheels, 245 tires. · T2/T3 Mustang GT 5.0L and V6 (11-14) may remove upper grille fog lights, replace with mesh or screen. · Hyundai Veloster Turbo 2018-2021 classified in T3 at 3050 lbs with 1584cc engine, 245 max tire size, specific suspension and brake modifications allowed. · T3 Volkswagen GTI and Jetta GLI now permit Verkline WAS-048 adjustable rear camber arms. · EP 79-85 RX-7 12A/13B brake spec simplification removes hub/rotor weight minimum allowance. · EP 280Z carburetor option adds Hitachi-SU 1bbl 46mm throttle bores alongside fuel injection. · EP Mazda RX-2, RX-3, RX-4, and 12A RX-7 now allow 2 bbl fuel injected throttle body w/ 42mm chokes on dual-y manifold. · EP Mazda RX-2, RX-3, RX-3SP, and RX-4 minimum weights reduced 50–52 lbs across all spec lines. · EP Triumph TR8 78-81 now allowed to run dry sump. · EP, FP, HP cylinder head ports limited to 1 inch maximum depth matching from mating surface. · EP Prep 280ZX (79-83) added to spec lines with 2425–2546 lbs, 2760cc SOHC 6-cyl, fuel injection, 12.0:1 compression limit, .500" valve lift limit. · T3 Nissan 350Z and 370Z remove SPC Control Arms 72130, 72125, 72123; permit performance alternative front upper control arms. · T3 Nissan 350Z loses up to 75 lbs and gets 44mm restrictors; 370Z loses 100 lbs. Wheels widened front and rear. · T3 Ford Mustang EcoBoost 2015- turbo inlet restrictor increases from 34mm to 35mm TIR. · T5 class added as regional-only; T5 tyres maximum width 225, minimum aspect ratio 45. · T2-T5 Touring front and rear suspension maximum negative camber changed to 3.5 degrees. · T3 Solstice GXP intercooler options expanded: Hahn HIC-1150 or Dejon FIC-SSA replaced with Performance alternative. · T3 Subaru BRZ 2022- minimum weight up to 2975 lbs; spring rate to 1000 F/R, brake parts allowed without penalty. · VW New Beetle 2.5L 5-cyl added to EP at 2400–2520 lbs, 2480 cc, fuel injection, comp ratio 12.0:1 max, valve lift 0.500" max. · EP Mazda RX-7 12A/13B gains fuel injection option on dual-y manifold with 42mm choke(s). · EP VW Corrado 92-95 stroke corrected to 90.3 mm, displacement to 2792 cc. · T3 Honda S2000 hardtop clarified: OEM, Mugen P/N 0000-04-2312, or aftermarket permitted if OEM roof silhouette retained. · T3 Pontiac Solstice GXP Coupe/Convertible 07-09 tire runout increases from 35mm to 36mm TIR. · BMW 320i (14-15) classified in T3 at 3050 lbs with 18-inch wheels, 255/275 tires, 3.08 final drive. · T3 Subaru BRZ (2022-) and Toyota GR86 (2022-) permit 25mm front and 22mm rear sway bars, OEM trunk spoiler. · EP Subaru BRZ and Toyota 86/Scion FR-S model year ranges updated to 13-20. · SRF tire rule wording changed from 'Tires: must be run as delivered' to 'Tires must be run as delivered.' · SRF brake rotor minimum thickness reduced from 13.25 to 12.20mm; seal and air filter rules clarified. · EP Mazda MX-5 Global Cup 16-22 minimum weight set to 2400 lbs; sequential gearbox allowed with +150 lbs penalty. · BMW 128i (08-13) classified in EP at 2700 lbs minimum with stock throttle body, 11.0:1 compression ratio, 0.400 in. valve lift limits. · EP/FP/HP open cars may now use carbon fiber hardtops if they retain OEM appearance in all exterior profiles. · T3 Honda Civic Si (2017-) spec clarified: wheels to 10" wide allowed with 50 lb. penalty, 1-piece rotor required. · Porsche Boxster Base 2005-2008 newly classified in T3 at 3000 lbs minimum weight. · T2-T4 Touring cars with alternative springs may use performance top hats with spherical bearings on shocks and struts. · T3 Subaru BRZ and Toyota 86 (2022-) wheel size corrected to 18 x 8 in., gear ratios and final drive specified. · EP Mazda RX-8 13B carburetor rules clarified: dual 2bbl carb, fuel injected throttle body, or stock fuel injection permitted. · EP and FP Production clarifies idle control valve rules: stock devices allowed original, removed with blocked ports, or mechanical replaced with electronic stock type. · T2-T4 cars model year 2018+ may use non-OEM ECU with 75 lb weight penalty via spec line adjustment. · T3 Ford Mustang V6 (11-14) minimum weight reduced to 3350 lbs. · T3 Subaru STI 15-20 now allows SPC lower control arm 67660. · EP BMW Z3 2.5L intake restrictor reduced from 59mm to 58mm flat plate. · Ford Mustang 99-03 classified to EP at 2700/2768/2835 lbs; 94-98 Mustang weight reduced to 2550/2614/2678 lbs. · EP, FP, HP Improved Touring cars may use any DOT-approved tire per section 9.3.45 in Production class. · T3 BMW 330i/Ci 01-06 loses 60 lbs to 3125 and runs 245 tyres instead of 275. · T3 Nissan 370Z 09-16 and 370Z NISMO 09-13 weight increased to 3375 lbs. · T3 FWD models standardized to 36mm turbo inlet restrictor; Focus ST brakes enlarged, final drive changed to 4.06 (1-4) 2.95 (5-6); GTI 14.5-17 gear ratios revised DSG/STD. · T2-T4 grill openings may remove non-metallic webbed false sections; 16 square inch limit removed. · T3 Spec Lines Subaru BRZ TS (13-21) added to class specification wording. · T3 VW GTI/Jetta GLI allows any 4-piston brake kit instead of StopTech only, max 355mm x 32mm. · EP, FP, HP classes allow stock/original idle control devices unmodified or completely removed with openings blocked. · EP Porsche 968 (92-95) now allows dry sump. · EP 1979-1985 Mazda RX-7 12A and 13B weight reduced by 50-53 lbs across all configurations. · EP Porsche 968 intake valve size increased from 37 to 39.0 mm. · EP, FP, HP front-wheel-drive cars may alter body and suspension to install alternate transmission, transaxle, and axle shaft. · EP BMW Z3 2.5L allows alternate throttle body from 92-95 325i with Turner adapter; head casting 1738400 permitted with specific blocks. · T3 Scion FR-S/Toyota 86 GT and Subaru BRZ lose 75 lbs, to 2675 lbs minimum weight. · 2022+ Subaru BRZ and Toyota 86 newly classified in T3 at 2750 lbs with 245 max tires. · T2-T4 clarified: grill opening area may increase max 16 sq in for radiator cooling only, retaining factory mesh shape. · T3 BMW 335i eligible model years narrowed from 08-13 to 07-10. · T3 BMW 135i model years restricted from 08-13 to 08-10. · T2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted. · T3 Nissan Z 350Z and 370Z suspension control arm options expanded from 'and' to 'or' for SPC parts. · T2, T3, T4 clarify that spec lines listing permitted or allowed parts are alternatives to category rules, not replacements. · EP Porsche 944S2 89-91 requires 56mm flat plate intake restrictor; comp ratio max 12.0:1, valve lift max 0.500". · HP Corolla GTS RWD (84-87) added at 2300 lbs; HP Corolla FX16 FWD (87-88) added at 2260 lbs; old Corolla (84-87) removed. · SRF front wet tire changes from P185/60R13 H20 to P185/65R13 W2; SRF3 adds mandatory G301048 restrictor plate Jan. 1, 2022. · T3 BMW Z4 M Coupe model years corrected from 2007 to 06-08. · T3 Subaru STI 15-20 weight increases 150 lbs, to 3350. · T4 Volkswagen Passat, Jetta 1.8T adds 2014 model year to eligible years. · T3 BMW 323Ci/Is 98-00 minimum weight reduced from 3100 to 3000 lbs. · Subaru STI (15-20) newly classified in T3 at 3200 lbs minimum weight with 37mm turbo inlet restrictor required. · HP Toyota MR-2 1.6L (85-89) track corrected to 15.47 inches front and rear. · Honda S2000 (00-03) reclassified as EP Prep with F22c engine option: 1997cc or 2157cc, weight 2450–2636 lbs depending on displacement. · EP Nissan 240-SX S13/S14 loses 200-210 lbs minimum weight; comp ratio rises to 12.0:1, valve lift to .500. · SRF wet tyres add Hoosier P185/60R13 W2 front and P205/60R13 W2 rear as alternatives to H20. · SRF adds SADEV-SRF3 6-speed sequential option with final drive 3.20 versus OEM 5-speed 3.85. · SRF seal procedures clarified: unsealed components need CSR inspection and logbook notation instead of engine removal. · EP Lotus/Caterham 7 America carburetor changed from IT fuel injection prep to fuel injection. · Daimler SP 250 classified in EP at 2165 lbs with 2548 cc OHV 8-cylinder engine. · T3 Porsche Spec Boxster minimum weight reduced from 2600 to 2550 lbs. · T3 Porsche Cayman 06-08 wheel size changes from 18x8 to 18x9 inches. · T3 Mazda MX-5 Global Cup Miata ND2 with sequential gearbox allowed +100 lbs weight adder. · EP, FP, HP clarifies percentage weight penalties sum first, then apply to base weight, rounding to nearest pound. · SRF3 alternator pulley restricted to P/N G902130 or G902130A, 12oz minimum weight. · T3 Honda Civic Type-R 2020+ allows brake rotor 45251-TGH-A01 with 25 lb penalty. · 84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lbs weight, 1998cc SOHC, dual 32mm carbs. · FP Fiat X1/9 brake rotors change to 257 (10.1) x 12 (.407) solid disc. · EP Mazda MX-5 year range corrected from 06-14 to 06-15. · T3 Porsche Boxster/Boxster S (00-04) now permits any OEM or aftermarket hardtop retaining OEM roof silhouette. · T3 Mazdaspeed3 07-09 and 10-13 now allow CorkSport Gen-6-999-10 or Autotech 10-127-100K fuel pumps. · Mazda 3 S 04-08 classified in EP at 2350 lbs minimum, 2.26L DOHC, 12.0:1 compression, .500" valve lift limit. · T2-T4 clutch disc and pressure plate must be at least 95% of factory OEM weight. · Porsche Cayman 06-08 classified in T3 with 2687cc engine, 3050 lbs minimum weight, 18-inch wheels, 245 tires. · SRF and SRF3 mandatory identification simplified: removed Ford Performance and Blue Oval decals, kept Hoosier logo placement. · T3 Ford Mustang EcoBoost gets 35mm TIR; Nissan 350Z DE Motor down 25 lbs to 3250; Mustang V6 down 50 lbs to 3475, restrictor tightened 55mm to 58mm. · Toyota Supra 2020- newly classified in T2 at 3450 lbs minimum weight with 295 tire and 19-inch wheels. · T3 Chevrolet Camaro LT-I4 Turbo 1LE reclassified to 2016- model year, max tire size 275, TIR required 35mm. · T2 Ford Mustang GT 5.0L (15-17) gear ratios corrected to 3.66, 2.43, 1.69, 1.32, 1.00, 0.65 or 4.17, 2.34, 1.52, 1.14, 0.87, 0.69. · T3 Spec Boxster tire size increased from 225 to 245 DOT, permitting wider tires. · EP Austin-Healey 3000 Mk. I, II, III now allows TR-6 front calipers and discs as alternate. · BMW M2 CS Cup 2020+ classified in T2 at 3625 lbs with 2979cc engine, 10.5x18 wheels, 295 tires. · T3 and T4 Mazda MX-5 06-15 now allow Mazda Transmission kit part # 0000-02-5700. · T2 and T3 Nissan 350Z and 370Z permit 44011-RC350 rear caliper kit and SZ350 rotors. · T4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, adds 25 lb penalty. · T3 and T4 FR-S, 86, and BRZ year ranges capped: T3 at 2021, T4 at 2017-2021. · FP Volkswagen Golf and Jetta 1.8 lose 50 lbs each, to 1900. HP Jetta GLI engine code removed. · EP, FP, HP Level 1 and Level 2 induction systems: clarified carburetor and fuel injection rules, jets/needles/rods unrestricted in Level 2. · EP Datsun SRL 311U Roadster minimum weight reduced to 1925 lbs from 2000 lbs. · EP Triumph TR8 78-81 weight reduced from 2600 to 2500 lbs. · SRF shocks, springs, bump stops sealed; rear springs 412-429 lbs/in P/N 280390 only; previous parts no longer allowed. · T3 Alfa Romeo 4C Launch Edition now allowed in Spec Lines. · HP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches. · Honda Civic Type R (2017-) classified in T3 at 3350 lbs with 1996cc engine, 245 max tire, 20-inch max wheel. · EP BMW Z3 2.5L iron block casting 1738566-C designation removed, wording clarification only. · T3 Honda Accord (2009) V6 manual classified: 3471cc, 3450 lbs, 245 max tire, 19-inch wheels. · Porsche 911 S 67-68 classified in EP at three weight levels: 1800, 1845, or 1890 lbs. · T3 Mazda MX-5 Global Cup Miata ND2 2016-2019 must meet all ND2 Global Cup rules without appendix reference. · T3 VW GTI FSI gains turbo inlet restrictor allowance to 60mm, R32 brakes, Stoptech 4-piston kit, and Neuspeed intake options. · Cannot read: letter references external document #27663 not provided. · EP BMW 2.8L, 328i E36/E46, and 325i E36 blocks now iron only; 325i E46 aluminum only. · SRF3 shock absorber brand restriction removed; all shocks must be sealed by Enterprises. · 2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine and Eibach PN# 2563.140 springs allowed. · T3 Nissan 350Z Spec 2 DE Engine loses 57mm flat plate restrictor requirement. · 1990-1994 Mazda Protege classified in FP Pre at 2150–2258 lbs with 1839cc DOHC engine, fuel injection. · HP Mini Cooper model year ranges for convertibles revised: 02-06 now includes 05-08, 07-13 now includes 09-15. · SRF3 bump stop now must be SCCA P/N 280407 only, no modifications, optional, max one per shock. · SRF shock absorber bump stop clarified: only SCCA P/N 280407 allowed as delivered, maximum one per shock, effective 05/01/2020. · T3 Ford Mustang EcoBoost and V6 sway bars allowed up to 35mm front, 25mm rear. · T3 BMW Z3 M & Coupe 1998-1999 weight reduced from 3350 to 3150 lbs. · EP Caterham 7 Spec Line removes redundant suspension note, clarifies engine prep limits and comp ratio to 10.0:1. · EP BMW Z3 2.5L compression ratio capped 12.0:1, valve lift .500, 59mm restrictor required; Z3 2.8L same limits added; 944S2 compression 12.0:1, valve lift .500, 56mm restrictor required. · EP BMW 325is M-Technic loses 100–105 lbs across three weight configurations, to 2550–2678. · HP Datsun 510 gains 40 DCOE carburetor option alongside existing 40 DCN and 36mm DCNVH choices. · EP BMW fuel injected throttle body maximum inside diameter set to 64mm. · T3 05-10 V8 Mustang allowed parts clarified: strut tower brace, radiator, springs to 500 lbs/in front and 300 lbs/in rear, sway bars, damper kit. · T3 Ford Mustang Coupe GT & Shelby GT 4.6L 05-10 adds permitted final drive ratios: 3.31, 3.55 or 3.73. · HP Datsun 1200 carburetor choke size increases from 26mm to 30mm. · BMW 330i 2006-2012 added to T3 with 2996cc engine, 3200 lbs minimum weight. · Pontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18 x 9.5 inches, Sky weight drops to 3200 lbs. · Mazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01. · T3 adds 2017 Ford Fiesta ST, 1596cc, 2600 lbs minimum weight, 245 max tire, 17x9 wheels. · FP and EP Mazda Miata models standardized to 55mm throttle body diameter; brake spec clarified. · T2 requires onboard fire system; T3 and T4 may have one per GCR 9.3. · T3 Ford Mustang EcoBoost 2015- gains three transmission gear ratio options. · T3 Nissan 350Z and 370Z HR engines: restrictor plate enlarged from 37mm to 42mm, weight increased 50-100 lbs. · T3 Mazda MX-5 Global Cup Miata (2016-) tires now 215/610 R17 BF Goodrich G-Force Slick or wet; removes touring tire requirement. · T3 05-10 Mustang GT 4.6L suspension upgrades allowed: tower braces, radiator, 500/300 lbs/in springs, sway bars, dampers, control arms, shocks, driveshaft. · T3 BMW SpecE46 updates to SpecE46 rules Version 2.6 to 2.7, tire width to 225 maximum. · T3 Subaru WRX 02-05 minimum weight drops 100 lbs to 3250. · Mazda RX-8 Base/R3 (04-12) reclassified in T3 and T4 to include Sport and GT variants. · Toyota 86 GT (2017-) added to T3 and T4 Spec Line. · SRF rain and brake rule wording updated; supersedes GCR 9.3.32.B.2 effective 1/1/202 through 12/31/2024. · EP, FP, HP cylinder head rules reorganized for clarity; no performance change. · SRF bans tire warmers and cooling methods other than natural air convection or conduction. · SRF front nose weight minimum reduced from 35 to 32 lbs. · SRF3 reclassified as Spec Racer Ford 3 with 1.6L conversion; SRF2 becomes Regional Only Class. · T3 Scion FR-S/Toyota 86 and Subaru BRZ year range extended from 13-17 to 13-20. · T3 Mazda NC MX-5 gains two alternate six-speed and one five-speed transmission gear ratio option. · FP and HP Austin-Healey Sprite Mk I and MG Midget variants may replace rear bodywork aft of cockpit with stock-appearing alternate material components. · EP Mazda MX-5 Global Cup classification year changes from 16-18 to 16-19. · Production suspension rule clarifies spindles, hubs, bushings, bearings, ball joints unrestricted. · Production carb rules clarified: carburetor options, fuel injection throttle body dimensions, and intake manifold restrictions reorganised and refined. · EP, FP, HP carburetors clarified: jets, needles, metering rods, needle valves unrestricted; choke parts removable; permitted optional carburetors listed. · T2-T4 spare tire/wheel rules clarified: removable covers can be removed with hardware and bracketry. · EP Mazda MX-5/Miata eligibility years expanded from 1999-2002 to 1999-2005. · T3 Mk7 GTI gains R32 brake package, 4-piston Stoptech kit to 355mm, and ECS street shield allowance. · SRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102. · T3 BMW E36 M3 96-00 allows alternate sway bars, 35mm front and 27mm rear. · SRF3 nose assembly must use approved multi-piece design; no modifications allowed except as specified. · 09-12 Porsche Cayman newly classified in T3 at 3150 lbs with 2900cc engine. · EP Mazda RX-8 firewall modification allowed for 13B engine fitment in stock location. · SRF3 brakes now allow Hawk Blue 9012 pads P/N 801993 only; shocks simplified to Penske P/N 280396 sealed assembly only, with optional SCCA Enterprises bump rubber P/N 280407 from 05/01/2020. · T3 Chevrolet Camaro LT-I4 Turbo 1LE (2019-) classified with 1998 cc engine, 3450 lbs minimum weight, 245 max tire size. · T3 Honda Civic Si 2017- minimum weight reduced 100 lbs, to 2900. · Honda Civic Si 2017+ with alternate cage classified in T3 at 3075 lbs minimum weight. · T3 classifies 2014-2017 Volkswagen GTI with 35 mm turbo inlet restrictor, 3080 lbs DSG, 3050 lbs standard. · EP, FP, HP clarified: tapered holes in ball joints now allowed for bolt conversion; wheel bearings and hubs unrestricted at any wheel. · EP open cars may now use aftermarket hardtops if they retain OEM appearance; specific model hardtop allowances removed. · BMW E36 M3 (96-00) BMWCCA I Sport newly classified in T3 at 3100 lbs minimum weight. · EP Mazda RX-7 12A and 13B (79-85) lose up to 80 lbs; 13B (86-91) loses up to 79 lbs. · T1-LP Ford Mustang GT 5.0L 2018+ classified at 3400 lbs with 65mm flat plate restrictor. · T3 Subaru WRX (2015-) classified at 3275 lbs with 35mm turbo inlet restrictor required. · T4 Mazda MX-5 Club (06-15) and (2016-), T3 MX-5 Cup and Miata (2016-) hardtop rules clarified; wording changes to permitted parts and specifications. · T3 Mazda MX-5 NC 06-15 wheel width increases from 17x7 to 17x8. · T3 Mazda MX-5 NC 06-15 now allows any aftermarket header. · T3 Saturn Sky intercooler tolerance increases from 32mm to 35mm TIR; new calipers and springs permitted. · T2, T3, T4 now allow any thermostat serving only OE intent, previously restricted. · T3 Subaru Legacy GT/Spec B 05-09 newly classified with 2457cc, 18×9 wheels, 245 tires, 3300 lbs. · T3 and T4 Mazda MX-5 Miata eligibility capped at 2018 model year, effective 2019-03-01. · T3 Mazda Mazdaspeed3 07-09 front brake disc increases to 320mm vented, rear to 300mm solid. · T4 Ford Fiesta ST years corrected to 14-; T4 Fiat 124/Abarth Edition years added 16-18; battery rule clarified. · T3 BMW SpecE46 rules reference updated from Appendix N to Version 2.6 Effective Jan 1, 2019. · T3 Nissan 350Z Track/Touring/Standard/Nismo 03-08 permitted to use Nissan brake kit part number 41000-BRKIT. · T1-T3 spec cars receive clarifications on permitted modifications, documentation requirements, and rule conformance; no performance changes. · T2-T4 subframe bushings may now be replaced with non-spherical bushings of any material. · T3 field loses 50 lbs across 27 cars including Acura TL, BMW 335i, Camaro, Mustang, Miata, RX-8, 370Z, WRX. · T3 Ford Mustang EcoBoost gains Ford Motorsports or Brembo brake kit options, +100 lb. · T3 FR-S/86 and BRZ: wheels to 17x9, tires to 255, weight to 2750 lbs. · T3 BMW SpecE46 now permits any DOT tire up to 225 width as alternate to spec tire.showhide
EP Effective date for Jan 2025 GCR updates #37654inductionslowerEP BMW Z3 2.5L requires 52mm flat plate intake restrictor; Z3 2.8L 55mm; 328i/is E36 58mm; 328i/ci E46 58mm; 325i/is E46 56mm; 325i/is E36 56mm; 325is M-Technic 56mm.
T3 350z BOP #37427inductionfasterT3 Nissan 350Z HR Engine FPR restrictor increases from 47mm to 49mm.
T3 Request to Classify Club Spec in Appropriate Touring Classes #37523cars addedneutralFord SCCA Club Spec Mustang classified T3 at 3350 lbs with driver; Mazda SCCA Club Spec MX-5 classified T4 at 2500 lbs with driver.
EP Request to Reduce Weight of BMW 325i/is E30 (84-91) Spec Line #37119weight -50 lbsfasterEP BMW 325i/is E30 (84-91) weight reduced 50–52 lbs across three spec lines to 2150, 2204, 2258.
T3 Remove spec lines that have expired #37269removedneutralT2, T3, T4 remove nine, nine, and thirty-six expired spec lines respectively, effective 2025-01-01.
T3 Request to Move Spec Mustang to Touring 3 (from T2) #37080cars addedneutralFord Spec Mustang moves to T3 with 44mm bore restrictor, 275 max tire, 3450 lbs minimum weight.
T3 3.7 Mustangs BoP #37186inductionfasterT3 Ford Mustang V6 (11-14) and (15-17) now permit cold air intake.
EP Triumph GT6 Adjustments #37112inductionslowerEP Triumph GT6 switches to three Weber 40 DCOE carbs with 28mm chokes, weight rises 50 lbs to 1990.
T3 Amend TIR Placement on VW #36175wordingneutralT3 VW Golf R (12-13 and 15-18) 36mm TIR placement now allows OEM turbo inlet, removing 60mm distance limit from impeller.
T3 Redundant Verbiage Regarding Mustang Spec Lines for Driveshaft #36484wordingneutralT2 and T3 Mustang spec lines remove redundant driveshaft alternate/aluminum allowance wording.
T3 Fuel Emissions Components #37076wordingneutralT2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors.
T3 fix brake wording #37129wordingneutralT2, T3, T4 brake component wording clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter.
T3 Evaporative emissions systems #37130wordingneutralT2, T3, T4 fuel cell cars may remove charcoal canisters, emissions valves, and sensors.
T3 Allow Spec MX5 upgrade kit for 2009-11 RX8 S2 Transmision #37140wordingneutralT3 and T4 Mazda RX-8 and MX-5 permit transmission kit #0000-02-5700.
T3 Move Spec Boxster to T4 #37158cars addedneutralPorsche Spec Boxster moves to T4, minimum weight 2750 lbs, requires 3 Super Tour events before Runoffs eligibility.
T3 BMW 320i Spec Line #37204wordingneutralT4 BMW 320i 14-15 Spec Line expires 12/31/24 removed; Turner Motorsports intercooler #024703TMS02 allowed.
T3 Classification for a 2005 Cadillac CTS 3.6 liter 6 speed manual #37224cars addedneutralCadillac CTS 02-07 3.6L classified in T3.
T3 Request to Classify BMWs #37226cars addedneutralT3 BMW 328i/330i (06-12) model name updated; BMW 320i (14-15) newly classified at 3050 lbs.
T3 Make adjustments to the 2015 STI Spec line #37246tyres & wheelsfasterT3 Subaru WRX STI max model year extended to 21, max tire size increased to 275.
T3 class a civic #37294cars addedneutralT3 Honda HPD Civic Si FE1 newly classified with 1498cc engine, 18x8 wheels, 245 tires, 2950 lbs minimum weight.
T3 Older STI in T3 #37300weight -100 lbsfasterT3 Subaru WRX STI 03-07 drops 100 lbs to 3200; Legacy GT/Spec B 05-09 drops 150 lbs to 3200.
EP 1275 HP Spridget Level 2 Only #36518enginefasterHP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1.
EP NA Miata Track Width Correction #36902wordingneutralEP Mazda Miata front and rear track widths increased to 1516/1534 mm (59.7/60.4 in.) across all generations.
SRF3 Update SRF3 Air Filter Rule #36681wordingunclearSRF3 air filter rule removes K&N RC-9160 option, leaving only P/N WM301020 allowed.
SRF3 Hoosier Tire Decal Placement #36739wordingneutralSRF3 Hoosier logo placement changes from four decals to three decals in different locations.
SRF3 Update to Letter 36619 with new Hoosier Contingency Decal Info #36624wordingneutralSRF Hoosier decal requirement reduced from four decals in specific locations to three decals with simpler placement rules.
EP Errant entry in HP production line item #36231wordingneutralHP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in).
SRF3 Update Rain Tire Rule and Hoosier Decal Placement #36436tyres & wheelsslowerSRF wet tires: P185/60R13 H20/W2 option removed; P185/65R13 W2 front now required with P205/60R13 W2 rear.
T3 Honda Civic Si (2017+) #36249inductionfasterT3 Honda Civic Si (2017-2021) restrictor removed, weight to 2950 lbs, Runoffs eligibility requires 3 Super Tour events.
T3 Subaru Reliability Help #36284wordingneutralT3 Subaru STI (15-20) and WRX STI (03-07) permitted to use OEM spec block #IAG-ENG-S550 and head studs.
T3 spec line for 36073 #36338cars addedneutralAudi TT Coupe 08-14 classified in T3 with 36mm TIR restrictor, 1984cc, 3200 lbs minimum weight.
T3 36131 #36339cars addedneutralT3 Mazda MX5 Miata/Club/RF (19-24) newly classified at 2550 lbs, 17x8.5 wheels, 245 tyres, 280 mm brakes.
T3 Mustang T2/T3 #35877wordingunclearFord Mustang GT 5.0L and V6 now permit Track/Performance Package parts in T2 and T3.
T3 T2-T4 Driveshaft Mistake...? #36050weightfasterT2-T4 Ford Mustangs: remove 25 lbs penalty for non-OEM driveshaft, clarify alternate driveshaft allowances.
T3 E&O: #35174 (Derek Chan) 350Z Parity Request #36116inductionfasterT3 Nissan 350Z DE engine now permits cold air intake.
T3 B8/8.5 Audi S4 T3 and T2 #36195cars addedneutralAudi S4 (2000-2002) moves to T3 with 3400 lbs minimum weight, 38mm turbo inlet restrictor required.
T3 Z4 Roadster Eligibility #36196cars addedneutralT3 BMW Z4 3.0si expands to include 3.0i Roadster and Coupe (07-08); hardtop permitted with positive fasteners.
EP NIssan 300ZX Z31 to EP #35830cars addedneutralNissan 300ZX 84-89 classified to EP at 2550 lbs minimum, 2960cc 6-cyl SOHC, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit.
EP RX7 1993 and Up Request In EP Spec Lines, classify #36031cars addedneutralMazda RX-7 92-97 newly classified EP Prep Level 2 at 2200–2310 lbs with 13B 6-port rotary engine.
EP Clean-up Multiple EP RX-8 Spec Lines In EP #36156wordingneutralEP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains.
SRF3 SRF3 Alternator Pulley Update In #36095weightfasterSRF3 alternator pulley minimum weight reduced from 12 oz to 11 oz.
T3 Global MX5 Tre change #36046tyres & wheelsunclearT3 Mazda MX-5 Global Cup Miata ND1/ND2 tire size changes to 225 DOT specification.
T3 Allow T4 and T3 RX8 to Disable/Remove Factory Oil Inj. #35761engineunclearT3 and T4 Mazda RX-8 may remove or disable factory oil injection system.
T3 Driveshafts #35916weightslowerT2, T3, T4 driveshafts may use alternative materials or one-piece units; non-OEM adds 25 lbs.
T3 Audi S4 HST requirement #35918wordingneutralAudi S4 00-02 in T3 must compete in 3 Super Tour events before Runoffs eligibility.
EP GCR Correction - Redundant HP Spec Lines #35623wordingneutralHP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve, Scirocco 1588.
T3 Spec Z Interchange in T3 #34416tyres & wheelsfasterT3 Spec Z 350Z rear wheel width increases to 10 inches; HR Engine restrictors change from 42mm to 44mm.
T3 please classify 2000-2002 Audi s4 #35306cars addedneutralAudi S4 2000-2002 classified in T3 at 3400 lbs with 38mm turbo inlet restrictor required.
T3 Reorganize Spec Lines #35375wordingunclearT2-T4 Spec Lines remove wheelbase requirement, replace with Required Restrictor specification.
T3 370Z Brake Rotor Size Correction #35487suspension & brakesneutralT2 and T3 Nissan 370Z brake rotors enlarged: front 320x28 to 355x32mm, rear 320x16 to 350x20mm vented.
T3 T3 V6 Mustang help #35526enginefasterT3 Ford Mustang V6 (11-14) restrictor requirement removed; (15-17) brake penalty reduced to +50 lbs from +100 lbs.
T3 Nissan 370Z - Brake System Allowance - Brake Booster #35556suspension & brakesneutralT3 Nissan 350Z and 370Z now allow brake booster vacuum regulator, must not be in-car adjustable.
T3 Mustang Help #35559inductionfasterT3 Ford Mustang 4.6L restrictor holes increased from 40 mm to 45 mm.
T3 Appeal for Retention of T3 Mazda RX-8 Spec Line (Letter #35378) #35577wordingunclearT3 Mazda RX-8 Spec Line retention appeal directed to letter #35584 for ruling.
T3 Request to Keep the Mazda Rx-8 in Touring 3 #35584wordingneutralMazda RX-8 04-12 expiration date removed; no longer expires 12/31/24.
T3 Subaru WRX (02-05) Appeal #35656wordingneutralT3 Subaru WRX (02-05) spec line expiration deadline removed; class now permanent.
EP Update 1988-1991 Civic to Match 1988-1991 CRX #35399weightfasterHP Honda Civic 1.5 (88-91) weight reduced to 2175 lbs base, 2229 lbs with power adder, 2284 lbs with two.
T3 15-18 Golf R Alignment with Existing GTI and R Speclines #35235tyres & wheelsfasterT3 Golf R 15-18 max wheel width increases to 9 inches, max tire size to 255.
T3 More Car Lightening Stuff #35319weightfasterT2, T3, T4 battery replacement wording simplified; OEM weight tolerance requirement removed.
T3 Open Strut Tower Brace Options for Ford Mustang V6 (11-14) #35322wordingneutralT3 Ford Mustang V6 (11-14) gains approved strut tower brace and sway bar kit options.
T3 Mustang ecoboost #35351inductionfasterT3 Ford Mustang EcoBoost 2015- intake restrictor increases from 35mm to 36mm TIR.
T3 Inclusion of B-C spec cars in T4 #35374cars addedneutralT4 now permits C-Spec cars to compete alongside B-Spec cars.
T3 T2-T4 Set expiration dates on spec lines #35378wordingneutralT2-T4 spec lines for 46 cars expire 12/31/24; appeal required to continue.
EP Request to Review Z3 2.5 Spec Line #35073weight +50 lbsslowerEP BMW Z3 2.5L weight increases to 2500 lbs, 2563 lbs with turbo, 2625 lbs with supercharger.
EP Miata Alternate Head #35253weight -50 lbsfasterEP Mazda MX-5 1.8L 1990-97 minimum weight drops to 2150 lbs; 1994-97 variants to 2000, 2050, 2100 lbs respectively.
EP Honda S2000 throttle body #35272inductionfasterEP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm.
EP Correction within Triumph TR8 Spec Line #35315wordingneutralEP Triumph TR8 dry sump allowance moved from carburetor line to notes section.
EP Correction to EP 924S/944 Spec Line #35317wordingneutralEP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs.
SRF3 Update SRF Rain / Brake Rule #34706wordingneutralSRF rain/brake light now requires Super Bright LEDs Inc. P/N PT-STRB-R24 with specific connector and rain light switch.
SRF3 Update SRF Brake Light Rule v1 #34853wordingneutralSRF requires Super Bright LEDs P/N PT-STRB-R24 rain/brake light with strobing capability and specific wiring.
T3 T3 Solstice Brakes #35106suspension & brakesslowerT3 Pontiac Solstice GXP front brake rotor increases from 296 to 355 mm vented.
T3 350Z Parity Request #35174weightslowerT3 Nissan 350Z DE motor loses 75 lbs to 3125; HR motor gains 47mm restrictors, up from 44mm.
T3 Requested Update of Model Years of 370Z #35231wordingneutralT3 Nissan 370Z model years expanded to include NISMO Edition through 2022.
T3 Update Request for 2010 Mustang GT 4.6 #35234wordingneutralT3 2010 Mustang GT 4.6 now allows 2013-14 GT style front/rear fascia, hood, and associated assemblies.
T3 SE46 Continued Parity/ Cold Air Intake request #35267weight -50 lbsfasterT3 BMW SpecE46 minimum weight drops 50 lbs to 2850.
T3 Please help the Subaru STIs. #35278weight +100 lbsslowerT3 Subaru STI (15-20) minimum weight increases 100 lbs to 3450; all three STI variants get larger turbo inlet restrictors.
EP Porsche 944/924S Rule Change Request #35002cars addedneutralEP Porsche 944/924S combines 2.5L and 2.7L variants with new weights: 2250–2415 lbs depending on engine and year.
EP Triumph GT6 Adjustments #35054weight -30 lbsfasterEP Triumph GT6 minimum weight reduced to 1800 lbs.
T3 Porsche Cayman Transmissions and Ratios #34891wordingfasterT3 Porsche Cayman (09-12) and (13-16) gear and final drive ratios adjusted; 09-12 6-SPD final drive 3.88 to 3.875, PDK 3.909 to 3.250; 13-16 6-SPD final drive 3.89 unchanged, PDK 3.91 to 3.250.
T3 2006-10 Volkswagen GTI - Weight Reduction request and KO4 Turbo #34414inductionfasterT3 Volkswagen GTI 06-10 turbo inlet restrictor increases from 36mm to 37mm.
T3 Adding Model Years to T3 Golf R Spec Line #34612wordingneutralT3 Volkswagen Golf R permitted model years extended from 15-16 to 15-18.
T3 Rear Camber Arms for T3 VW Golf R #34613wordingneutralT3 Volkswagen Golf R 15-16 now permits Verkline WAS-048 camber arms.
T3 Classing Spec E90 Cars in SCCA #34791cars addedneutralBMW Spec E9X classified in T3 at 2975 lbs, must conform to SpecE9X rules Version 2.10, tire max 225.
T3 TIR location requirement in VW Golf Spec lines #35048wordingneutralT3 VW Golf GTI and Golf R TIR location clarified to maximum 60mm from impeller.
SRF3 SRF Radiator Rule Update #34805wordingneutralSRF radiator rule clarified: P/N 480466 replaceable with Automotive P/N 1R698, CU698 or manufacturer equivalent with documentation.
EP Hub Note Clean Up In EP TR8 Spec Line #34649wordingneutralEP Triumph TR8 78-81 removes alternate front hub allowance note; stock hubs now required.
EP Triumph GT6 Adjustments #34662wordingunclearEP Triumph GT6 carburetors change from SU or Stromberg to 1.5" Auto-type.
EP Triumph GT6 Adjustments: Brakes #34663wordingneutralEP Triumph GT6 brakes may now use TR-6 standard or alternate calipers and discs.
T3 2012-2013 Golf R - added to T3 #34413cars addedneutral2012-2013 Volkswagen Golf R added to T3 as new entry with 1984cc engine, 3080 lbs DSG/3050 STD, 36mm turbo inlet restrictor.
T3 Rules Clarification for Mazda RX8 Spec Line #34395wordingneutralT3 Mazda RX-8 removes transmission/final drive pairing requirement; T4 removes same requirement, adds Mazdaspeed radiator and coil spring kit.
T3 rule book corrections #34437otherfasterT3 BMW 320i (14-15) gains aftermarket intercooler permission; T4 loses it.
T3 Allowing 255 Tire Width for Nissan 350z #34471tyres & wheelsfasterT3 Nissan 350Z and 370Z maximum tire width increases from 245 to 255.
T3 Ride Height Correction for the T3 Solstice. #34615wordingneutralT3 Pontiac Solstice GXP minimum ride height set to 3 inches.
EP Correct Intake Valve Size on 1500cc Midget/Spitfire #34419wordingneutralFP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44).
T3 2016+ Camaro 1LE - Max Wheel Diameter #34003tyres & wheelsfasterT3 Camaro V6 1LE and LT-I4 Turbo 1LE max wheel diameter increases from 18 to 20 inches.
T3 2022 Toyota GR Cup for T3 #34448removedneutralT3 removes Toyota 2022-up GR Cup and 2022-up GR86 Cup entirely from Spec Lines.
EP 914-6 Valve Size Correction #34185enginefasterEP Porsche 914-6 2.0L intake valves increase to 2.0 mm, exhaust valves corrected to 38.0 mm.
SRF3 Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheelsunclearSRF Hoosier wet front tire updated to P/N 46100 P185/60R13 H20 or W2.
T3 S550 Reconcile With S197 #34093weight -75 lbsfasterT3 Ford Mustang V6 (15-17) weight drops to 3400 lbs, brake penalties reduced to +100 lbs and +50 lbs.
T3 SE46 Parity Help #34178weight -50 lbsfasterBMW SpecE46 in T3 loses 50 lbs, to 2900.
T3 2022 Toyota GR Cup for T3 discussion #34234cars addedneutralT3 adds 2022 Toyota GR Cup and GR86 Cup, both 2387cc, 2700 lbs, 245/620R18 slicks, 332x32F/280x32R brakes.
SRF3 Update SRF Front W2 Rain Tire Part Number #34118tyres & wheelsneutralSRF Hoosier front rain tyre part number changes from 46100 to 46101 P185/65R13 W2.
T3 Request Spec E46 in T3 Weight Adjustment #33897weight -25 lbsfasterT3 BMW Spec E46 weight reduced 25 lbs, to 2925.
T3 E36 2.5L 323is Weight Reduction #33975weightfasterT3 BMW 323Ci/Is weight reduces to 2750 lbs from 3000 lbs.
T3 Update SpecE46 Spec Line to Current SpecE46 Ruleset #34016wordingunclearT3 BMW SpecE46 must conform to SpecE46 rules Version 2.10, updated from 2.7.
EP Investigate Parity of Z3 #33343inductionslowerEP BMW Z3 2.5L intake restrictor reduced from 58mm to 56mm flat plate.
T3 Request to all ECS Tuning inner-cooler to 06-10 VW GTI spec #33769wordingneutralT3 06-10 VW GTI, Jetta GLI allowed to use ECS Tuning performance alternative intercooler.
SRF3 Update SRF Brake Rule #33469suspension & brakesslowerSRF Renault Alliance solid front rotors banned; restrictor reduced 35mm to 34mm for 2011+ Kawasaki; minimum weight increased to 1100 lbs for 2009+ stock engines.
SRF3 Update SRF Bodywork Fitment Rule #33765wordingneutralSRF3 tail sections allowed on SRFs with GEN3 airbox shimming up to 19 mm; alternate dash panel P/N 180100 or 180101 relocated in rules.
T3 T3 Boxster S GCR request #33687wordingneutralT3 Porsche Spec Boxster tire rule updates to current SPB rules or any 245 DOT tire.
T3 OEM VW Steering Spindle Replacements 06-10 VW GTI and Jetta #33732wordingneutralT3 06-10 VW GTI and Jetta permitted to use OEM VW knuckles 3C0407253F and 3C0407254F.
T3 BMW 320I intercooler #33762otherfasterT3 BMW 320I now permitted to use aftermarket intercooler.
T3 Request to classify 2014 Base Cayman #33159cars addedneutralPorsche Cayman (13-16) classified in T3 at 3225 lbs with 2700cc engine, 18x9 wheels, 245 tires.
T3 Mustang OEM Grill Request #33333aeroneutralT2/T3 Mustang GT 5.0L and V6 (11-14) may remove upper grille fog lights, replace with mesh or screen.
T3 Hyundai Classification #33498cars addedneutralHyundai Veloster Turbo 2018-2021 classified in T3 at 3050 lbs with 1584cc engine, 245 max tire size, specific suspension and brake modifications allowed.
T3 Adjustable Rear Camber Arms for VW (All Generations) #33572wordingneutralT3 Volkswagen GTI and Jetta GLI now permit Verkline WAS-048 adjustable rear camber arms.
EP Revise 79-85 RX7 Brake Spec Line Allowance #33293wordingunclearEP 79-85 RX-7 12A/13B brake spec simplification removes hub/rotor weight minimum allowance.
EP Request alternate carburetors for EP 280z #33405wordingneutralEP 280Z carburetor option adds Hitachi-SU 1bbl 46mm throttle bores alongside fuel injection.
EP Fuel Injection 12a Mazda RX3 #33434inductionneutralEP Mazda RX-2, RX-3, RX-4, and 12A RX-7 now allow 2 bbl fuel injected throttle body w/ 42mm chokes on dual-y manifold.
EP Mazda RX3 - Weight Reduction #33436weight -50 lbsfasterEP Mazda RX-2, RX-3, RX-3SP, and RX-4 minimum weights reduced 50–52 lbs across all spec lines.
EP Request TR8 Dry Sump Allowance #33460enginefasterEP Triumph TR8 78-81 now allowed to run dry sump.
EP Review Limited Prep Port Matching Rules #33600wordingneutralEP, FP, HP cylinder head ports limited to 1 inch maximum depth matching from mating surface.
EP 280ZX Classification Request #33611cars addedneutralEP Prep 280ZX (79-83) added to spec lines with 2425–2546 lbs, 2760cc SOHC 6-cyl, fuel injection, 12.0:1 compression limit, .500" valve lift limit.
T3 350z SPC Upper Control Arm Safety Concerns #33020suspension & brakesneutralT3 Nissan 350Z and 370Z remove SPC Control Arms 72130, 72125, 72123; permit performance alternative front upper control arms.
T3 Request Help for 350z #33379weight -100 lbsfasterT3 Nissan 350Z loses up to 75 lbs and gets 44mm restrictors; 370Z loses 100 lbs. Wheels widened front and rear.
T3 Ecoboost Acknowledgement #33506inductionfasterT3 Ford Mustang EcoBoost 2015- turbo inlet restrictor increases from 34mm to 35mm TIR.
T3 Touring (T2-T5) Category #33617cars addedneutralT5 class added as regional-only; T5 tyres maximum width 225, minimum aspect ratio 45.
T3 ENO 9.1.9.2.D.1.e.1.a. #33651suspension & brakesneutralT2-T5 Touring front and rear suspension maximum negative camber changed to 3.5 degrees.
T3 Solstice GXP in T3 #33501wordingneutralT3 Solstice GXP intercooler options expanded: Hahn HIC-1150 or Dejon FIC-SSA replaced with Performance alternative.
T3 Another 2022 BRZ/86 T3 request #32945weight +225 lbsslowerT3 Subaru BRZ 2022- minimum weight up to 2975 lbs; spring rate to 1000 F/R, brake parts allowed without penalty.
EP Request to classify VW New Beetle 2.5L in EP #32725cars addedneutralVW New Beetle 2.5L 5-cyl added to EP at 2400–2520 lbs, 2480 cc, fuel injection, comp ratio 12.0:1 max, valve lift 0.500" max.
EP Request Rotary Injection on Dual Y manifold #32775inductionunclearEP Mazda RX-7 12A/13B gains fuel injection option on dual-y manifold with 42mm choke(s).
EP Request for Corrado Stroke & Displacement Correction #32985wordingneutralEP VW Corrado 92-95 stroke corrected to 90.3 mm, displacement to 2792 cc.
T3 S2000 Hard Top Clarification #32779wordingneutralT3 Honda S2000 hardtop clarified: OEM, Mugen P/N 0000-04-2312, or aftermarket permitted if OEM roof silhouette retained.
T3 T3 Pontiac Solstice- #33081tyres & wheelsslowerT3 Pontiac Solstice GXP Coupe/Convertible 07-09 tire runout increases from 35mm to 36mm TIR.
T3 Classify Car #32691cars addedneutralBMW 320i (14-15) classified in T3 at 3050 lbs with 18-inch wheels, 255/275 tires, 3.08 final drive.
T3 2022 BRZ Sway bar and lip spoiler. #32703suspension & brakesfasterT3 Subaru BRZ (2022-) and Toyota GR86 (2022-) permit 25mm front and 22mm rear sway bars, OEM trunk spoiler.
EP Subaru BRZ Model Years #32500wordingneutralEP Subaru BRZ and Toyota 86/Scion FR-S model year ranges updated to 13-20.
SRF3 SRF Tire Rule Update #32614wordingneutralSRF tire rule wording changed from 'Tires: must be run as delivered' to 'Tires must be run as delivered.'
SRF3 Brake, seal, and air filter clarifications #32670suspension & brakesfasterSRF brake rotor minimum thickness reduced from 13.25 to 12.20mm; seal and air filter rules clarified.
EP EP MX-5 Global Cup Car #32218weightslowerEP Mazda MX-5 Global Cup 16-22 minimum weight set to 2400 lbs; sequential gearbox allowed with +150 lbs penalty.
EP Please Class BMW 128i in EP #32370cars addedneutralBMW 128i (08-13) classified in EP at 2700 lbs minimum with stock throttle body, 11.0:1 compression ratio, 0.400 in. valve lift limits.
EP Inconsistency in Body Work Descriptions #32396aerofasterEP/FP/HP open cars may now use carbon fiber hardtops if they retain OEM appearance in all exterior profiles.
T3 correct wording #31750wordingneutralT3 Honda Civic Si (2017-) spec clarified: wheels to 10" wide allowed with 50 lb. penalty, 1-piece rotor required.
T3 2005-2008 Porsche Boxster 2.7 #31999cars addedneutralPorsche Boxster Base 2005-2008 newly classified in T3 at 3000 lbs minimum weight.
T3 Request Alternate Front & Rear Strut/Shock Top Hats #32452suspension & brakesneutralT2-T4 Touring cars with alternative springs may use performance top hats with spherical bearings on shocks and struts.
T3 2022 Subaru BRZ and Toyota 86 twins #32483wordingneutralT3 Subaru BRZ and Toyota 86 (2022-) wheel size corrected to 18 x 8 in., gear ratios and final drive specified.
EP Mazda RX8 with 13b Rotary #32170wordingneutralEP Mazda RX-8 13B carburetor rules clarified: dual 2bbl carb, fuel injected throttle body, or stock fuel injection permitted.
EP Request Idle control valve clarification #32178wordingneutralEP and FP Production clarifies idle control valve rules: stock devices allowed original, removed with blocked ports, or mechanical replaced with electronic stock type.
T3 Request to Allow the Use of Aftermarket ECU's in Touring #31067weightslowerT2-T4 cars model year 2018+ may use non-OEM ECU with 75 lb weight penalty via spec line adjustment.
T3 T3 Mustang V8/V6 #31959weight -50 lbsfasterT3 Ford Mustang V6 (11-14) minimum weight reduced to 3350 lbs.
T3 Subaru STI (15-20) Missing part #32294suspension & brakesneutralT3 Subaru STI 15-20 now allows SPC lower control arm 67660.
EP EP Adjustments #31858inductionslowerEP BMW Z3 2.5L intake restrictor reduced from 59mm to 58mm flat plate.
EP 1999 3.8L Ford Mustang to EP? #31635weightfasterFord Mustang 99-03 classified to EP at 2700/2768/2835 lbs; 94-98 Mustang weight reduced to 2550/2614/2678 lbs.
EP Improved Touring Tires #32064tyres & wheelsneutralEP, FP, HP Improved Touring cars may use any DOT-approved tire per section 9.3.45 in Production class.
T3 Touring 3 BOP adjustments for 2022 #31481weight +75 lbs
T3 BMW 330i Minimum Comp Weight #31606tyres & wheels -60 lbsfasterT3 BMW 330i/Ci 01-06 loses 60 lbs to 3125 and runs 245 tyres instead of 275.
T3 Adjust T3 370Z #31748weight +50 lbsslowerT3 Nissan 370Z 09-16 and 370Z NISMO 09-13 weight increased to 3375 lbs.
T3 TIR changes for FWD T3 models #31825inductionfasterT3 FWD models standardized to 36mm turbo inlet restrictor; Focus ST brakes enlarged, final drive changed to 4.06 (1-4) 2.95 (5-6); GTI 14.5-17 gear ratios revised DSG/STD.
T3 Reply to letter #31486/29879 T2-T4 Grill openings #31935aerofasterT2-T4 grill openings may remove non-metallic webbed false sections; 16 square inch limit removed.
T3 BRZ vs BRZ TS #32022wordingneutralT3 Spec Lines Subaru BRZ TS (13-21) added to class specification wording.
T3 Remove StopTech 4 piston BBK, allow any 4 Piston Kit - VW GTI #33082suspension & brakesneutralT3 VW GTI/Jetta GLI allows any 4-piston brake kit instead of StopTech only, max 355mm x 32mm.
EP Throttle Body and Idle Air #31800wordingneutralEP, FP, HP classes allow stock/original idle control devices unmodified or completely removed with openings blocked.
EP Porsche 968 Engine Questions #31831otherneutralEP Porsche 968 (92-95) now allows dry sump.
EP Request weight reduction for 1979-1985 Mazda RX-7 #31833weightfasterEP 1979-1985 Mazda RX-7 12A and 13B weight reduced by 50-53 lbs across all configurations.
EP Porsche 968 Engine Questions #31478enginefasterEP Porsche 968 intake valve size increased from 37 to 39.0 mm.
EP PCS E. 2. n. 4. Add Axle Shaft to Allow FWD the Same Freedom #31592wordingneutralEP, FP, HP front-wheel-drive cars may alter body and suspension to install alternate transmission, transaxle, and axle shaft.
EP BMW Z3 2.5L Spec Line #31724wordingneutralEP BMW Z3 2.5L allows alternate throttle body from 92-95 325i with Turner adapter; head casting 1738400 permitted with specific blocks.
T3 Request FRS/BRZ/86 T3 Weight Reduction #30818weight -75 lbsfasterT3 Scion FR-S/Toyota 86 GT and Subaru BRZ lose 75 lbs, to 2675 lbs minimum weight.
T3 Request to Classify 2022 Toyota 86 / Subaru in T3 & T4 #30931cars addedneutral2022+ Subaru BRZ and Toyota 86 newly classified in T3 at 2750 lbs with 245 max tires.
T3 Reply to letter 29879 T2-T4 Grill Openings #31486aerofasterT2-T4 clarified: grill opening area may increase max 16 sq in for radiator cooling only, retaining factory mesh shape.
T3 Please Adjust Years Allowed for BMW 335i to 07-10, not 08-13 #31530wordingneutralT3 BMW 335i eligible model years narrowed from 08-13 to 07-10.
T3 Please Adjust Years Allowed for BMW 135i to 08-10, not 08-13 #31531wordingneutralT3 BMW 135i model years restricted from 08-13 to 08-10.
T3 Request to clarify radiator hoses #31682wordingneutralT2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted.
T3 T3 Nissan Z Suspension Update #31728wordingneutralT3 Nissan Z 350Z and 370Z suspension control arm options expanded from 'and' to 'or' for SPC parts.
T3 Clarify Permitted/Allowed #31743wordingneutralT2, T3, T4 clarify that spec lines listing permitted or allowed parts are alternatives to category rules, not replacements.
EP 944S2 Restrictor #31396inductionslowerEP Porsche 944S2 89-91 requires 56mm flat plate intake restrictor; comp ratio max 12.0:1, valve lift max 0.500".
EP Classing Clarification for 1986 Toyota Corolla FX16 #31527cars addedneutralHP Corolla GTS RWD (84-87) added at 2300 lbs; HP Corolla FX16 FWD (87-88) added at 2260 lbs; old Corolla (84-87) removed.
SRF3 Three Updates to SRF Rules #31523tyres & wheelsunclearSRF front wet tire changes from P185/60R13 H20 to P185/65R13 W2; SRF3 adds mandatory G301048 restrictor plate Jan. 1, 2022.
T3 Request to correct model years BMW Z4 M Coupe #31371wordingneutralT3 BMW Z4 M Coupe model years corrected from 2007 to 06-08.
T3 Correct letter the 31327 #31563weight +150 lbsslowerT3 Subaru STI 15-20 weight increases 150 lbs, to 3350.
T3 Request to Classify 2014 VW Jetta 1.8t TSI #30436cars addedneutralT4 Volkswagen Passat, Jetta 1.8T adds 2014 model year to eligible years.
T3 Request Weight Reduction 323is #30765weight -100 lbsfasterT3 BMW 323Ci/Is 98-00 minimum weight reduced from 3100 to 3000 lbs.
T3 Class Newer STI in T3 #31327cars addedneutralSubaru STI (15-20) newly classified in T3 at 3200 lbs minimum weight with 37mm turbo inlet restrictor required.
EP E&O; MR2 Track #31120wordingneutralHP Toyota MR-2 1.6L (85-89) track corrected to 15.47 inches front and rear.
EP Request to Allow F22c Engine for 2000-2003 Honda S2000 #30548cars addedunclearHonda S2000 (00-03) reclassified as EP Prep with F22c engine option: 1997cc or 2157cc, weight 2450–2636 lbs depending on displacement.
EP Request a review of the S14 240SX in EP. #30873weight -200 lbsfasterEP Nissan 240-SX S13/S14 loses 200-210 lbs minimum weight; comp ratio rises to 12.0:1, valve lift to .500.
SRF3 SRF Wet Tires #30849tyres & wheelsneutralSRF wet tyres add Hoosier P185/60R13 W2 front and P205/60R13 W2 rear as alternatives to H20.
SRF3 SADEV-SRF3 Transmission #30926cars addedunclearSRF adds SADEV-SRF3 6-speed sequential option with final drive 3.20 versus OEM 5-speed 3.85.
SRF3 SRF Update Maintenance, Repairs and Seals #30961wordingneutralSRF seal procedures clarified: unsealed components need CSR inspection and logbook notation instead of engine removal.
EP Lotus/Caterham 7 America Request #30392wordingunclearEP Lotus/Caterham 7 America carburetor changed from IT fuel injection prep to fuel injection.
EP Reclassify Daimler SP 250 #30721cars addedneutralDaimler SP 250 classified in EP at 2165 lbs with 2548 cc OHV 8-cylinder engine.
T3 Follow-up to letter 29797-Porsche Spec Boxster in T3 Adjustment #30144weight -50 lbsfasterT3 Porsche Spec Boxster minimum weight reduced from 2600 to 2550 lbs.
T3 Wheel Size #30677tyres & wheelsfasterT3 Porsche Cayman 06-08 wheel size changes from 18x8 to 18x9 inches.
T3 Request weight adder to be applied to the Global Cup Miata ND2 #30730weightslowerT3 Mazda MX-5 Global Cup Miata ND2 with sequential gearbox allowed +100 lbs weight adder.
EP Clarify Application of Percentage Based Weight Penalties #30669weightslowerEP, FP, HP clarifies percentage weight penalties sum first, then apply to base weight, rounding to nearest pound.
SRF3 SRF3 Alternator Pulley #30684engineslowerSRF3 alternator pulley restricted to P/N G902130 or G902130A, 12oz minimum weight.
T3 Civic Type R Brake Rotors #29817weightslowerT3 Honda Civic Type-R 2020+ allows brake rotor 45251-TGH-A01 with 25 lb penalty.
EP Change Classification of 84-87 Mazda 626 from FP to HP #30350cars addedneutral84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lbs weight, 1998cc SOHC, dual 32mm carbs.
EP Fiat X1/9 brake rotors #30423suspension & brakesneutralFP Fiat X1/9 brake rotors change to 257 (10.1) x 12 (.407) solid disc.
EP NC MX-5 year range correction E&O #30503wordingneutralEP Mazda MX-5 year range corrected from 06-14 to 06-15.
T3 Requesting Variance on Hardtop #30093wordingneutralT3 Porsche Boxster/Boxster S (00-04) now permits any OEM or aftermarket hardtop retaining OEM roof silhouette.
T3 07-09 and 10-13 Mazdaspeed 3 Fuel Pump #30154wordingneutralT3 Mazdaspeed3 07-09 and 10-13 now allow CorkSport Gen-6-999-10 or Autotech 10-127-100K fuel pumps.
EP Please Classify Mazda3 in FP #30165cars addedneutralMazda 3 S 04-08 classified in EP at 2350 lbs minimum, 2.26L DOHC, 12.0:1 compression, .500" valve lift limit.
T3 Request consistency review in GCR #30263wordingslowerT2-T4 clutch disc and pressure plate must be at least 95% of factory OEM weight.
T3 Request to classify 2006-2008 Cayman #30315cars addedneutralPorsche Cayman 06-08 classified in T3 with 2687cc engine, 3050 lbs minimum weight, 18-inch wheels, 245 tires.
SRF3 Mandatory identification: #30223wordingneutralSRF and SRF3 mandatory identification simplified: removed Ford Performance and Blue Oval decals, kept Hoosier logo placement.
T3 2020 T3 Suggested Changes #30002wording -50 lbsslowerT3 Ford Mustang EcoBoost gets 35mm TIR; Nissan 350Z DE Motor down 25 lbs to 3250; Mustang V6 down 50 lbs to 3475, restrictor tightened 55mm to 58mm.
T3 2021 Toyota Supra #29567cars addedneutralToyota Supra 2020- newly classified in T2 at 3450 lbs minimum weight with 295 tire and 19-inch wheels.
T3 Chevrolet Camaro LT-I4 Turbo 1LE (2019-) Model Year to 2016- #30090tyres & wheelsfasterT3 Chevrolet Camaro LT-I4 Turbo 1LE reclassified to 2016- model year, max tire size 275, TIR required 35mm.
T3 Fix T2 Mustang spec line #30106wordingneutralT2 Ford Mustang GT 5.0L (15-17) gear ratios corrected to 3.66, 2.43, 1.69, 1.32, 1.00, 0.65 or 4.17, 2.34, 1.52, 1.14, 0.87, 0.69.
T3 Spec Boxster Tire Size #30159tyres & wheelsfasterT3 Spec Boxster tire size increased from 225 to 245 DOT, permitting wider tires.
EP Alternate Front Brake Rotors and Calipers for EP AH 3000 #29893suspension & brakesneutralEP Austin-Healey 3000 Mk. I, II, III now allows TR-6 front calipers and discs as alternate.
T3 Request to Classify BMW M2 CS #29523cars addedneutralBMW M2 CS Cup 2020+ classified in T2 at 3625 lbs with 2979cc engine, 10.5x18 wheels, 295 tires.
T3 Allow the SpecMX-5 Update Kit Into Touring 4 for the MX-5 #29681wordingunclearT3 and T4 Mazda MX-5 06-15 now allow Mazda Transmission kit part # 0000-02-5700.
T3 350Z Rear Caliper Replacement #29710wordingneutralT2 and T3 Nissan 350Z and 370Z permit 44011-RC350 rear caliper kit and SZ350 rotors.
T3 Request Mustang 8.8†rear axle replacement #29860weightslowerT4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, adds 25 lb penalty.
T3 Cap year range on all 86s #29908wordingneutralT3 and T4 FR-S, 86, and BRZ year ranges capped: T3 at 2021, T4 at 2017-2021.
EP Mk2 VW Consistency and Cleanup of FP and HP Spec Lines #29195weight -50 lbsfasterFP Volkswagen Golf and Jetta 1.8 lose 50 lbs each, to 1900. HP Jetta GLI engine code removed.
EP Correct Wording for Level 1 and Level 2 Induction Systems #29406wordingneutralEP, FP, HP Level 1 and Level 2 induction systems: clarified carburetor and fuel injection rules, jets/needles/rods unrestricted in Level 2.
EP Weight Reduction for Datsun Roadster #29409weight -75 lbsfasterEP Datsun SRL 311U Roadster minimum weight reduced to 1925 lbs from 2000 lbs.
EP EP TR8 Adjustment #29512weight -100 lbsfasterEP Triumph TR8 78-81 weight reduced from 2600 to 2500 lbs.
SRF3 SRF Shocks, Springs and Ride Height. #29688suspension & brakesneutralSRF shocks, springs, bump stops sealed; rear springs 412-429 lbs/in P/N 280390 only; previous parts no longer allowed.
T3 Alfa Romeo 4C Launch Edition #29531wordingneutralT3 Alfa Romeo 4C Launch Edition now allowed in Spec Lines.
EP 84-87 Toyota Corolla HP Wheel Diameter Allowance Proposal E&O #29458tyres & wheelsfasterHP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches.
T3 Request to Classify Honda Civic Type R in T3 #27840cars addedneutralHonda Civic Type R (2017-) classified in T3 at 3350 lbs with 1996cc engine, 245 max tire, 20-inch max wheel.
EP EP BMW Z3 Rule Clarification #28998wordingneutralEP BMW Z3 2.5L iron block casting 1738566-C designation removed, wording clarification only.
T3 Request to classify 2009 Honda Accord v6 manual #28913cars addedneutralT3 Honda Accord (2009) V6 manual classified: 3471cc, 3450 lbs, 245 max tire, 19-inch wheels.
EP Request to Classify Porsche 911 2.0L #28456cars addedneutralPorsche 911 S 67-68 classified in EP at three weight levels: 1800, 1845, or 1890 lbs.
T3 SADEV Sequential Gearbox #28763wordingneutralT3 Mazda MX-5 Global Cup Miata ND2 2016-2019 must meet all ND2 Global Cup rules without appendix reference.
T3 Request for competition adjustment for the MK5 GTI FSI engine #28802suspension & brakesfasterT3 VW GTI FSI gains turbo inlet restrictor allowance to 60mm, R32 brakes, Stoptech 4-piston kit, and Neuspeed intake options.
T3 Request to Add a Vehicle to the Roster (contd.) #27698cars addedunclearCannot read: letter references external document #27663 not provided.
EP BMW Cylinder Head Casting and Part Numbers #28708engineslowerEP BMW 2.8L, 328i E36/E46, and 325i E36 blocks now iron only; 325i E46 aluminum only.
SRF3 SRF Shocks #28791wordingneutralSRF3 shock absorber brand restriction removed; all shocks must be sealed by Enterprises.
T3 Request to Classify 2004 Mercedes Benz 320 CLK #27663cars addedneutral2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine and Eibach PN# 2563.140 springs allowed.
T3 Request Nissan 350Z Part Number change #28145enginefasterT3 Nissan 350Z Spec 2 DE Engine loses 57mm flat plate restrictor requirement.
EP Request to Classify 1990-1994 Mazda Protege #28381cars addedneutral1990-1994 Mazda Protege classified in FP Pre at 2150–2258 lbs with 1839cc DOHC engine, fuel injection.
EP Error in Mini Cooper Spec Line #28713wordingneutralHP Mini Cooper model year ranges for convertibles revised: 02-06 now includes 05-08, 07-13 now includes 09-15.
SRF3 Update Bump Stop Rule #28712suspension & brakesneutralSRF3 bump stop now must be SCCA P/N 280407 only, no modifications, optional, max one per shock.
SRF3 SRF Bump Stop Correction #27019wordingneutralSRF shock absorber bump stop clarified: only SCCA P/N 280407 allowed as delivered, maximum one per shock, effective 05/01/2020.
T3 2015 + Ford EcoBoost Mustang Sway Bars #28398suspension & brakesneutralT3 Ford Mustang EcoBoost and V6 sway bars allowed up to 35mm front, 25mm rear.
T3 Z3M Roadster Weight #28437weightfasterT3 BMW Z3 M & Coupe 1998-1999 weight reduced from 3350 to 3150 lbs.
EP Caterham 7 Spec Line #28498wordingneutralEP Caterham 7 Spec Line removes redundant suspension note, clarifies engine prep limits and comp ratio to 10.0:1.
EP Request to Review Horsepower Parity #27662engineslowerEP BMW Z3 2.5L compression ratio capped 12.0:1, valve lift .500, 59mm restrictor required; Z3 2.8L same limits added; 944S2 compression 12.0:1, valve lift .500, 56mm restrictor required.
EP E36 (92-95) Brakes Errors and Omissions #28058weightfasterEP BMW 325is M-Technic loses 100–105 lbs across three weight configurations, to 2550–2678.
EP Request to allow 40 DCOE carb for the Datsun 510 #28195inductionfasterHP Datsun 510 gains 40 DCOE carburetor option alongside existing 40 DCN and 36mm DCNVH choices.
EP Add Throttle Body Size these EP BMW Spec Lines #28422inductionslowerEP BMW fuel injected throttle body maximum inside diameter set to 64mm.
T3 Clarify 05-10 V8 Mustang Spring Rates Wording/Adjust Restrictor #28238wordingneutralT3 05-10 V8 Mustang allowed parts clarified: strut tower brace, radiator, springs to 500 lbs/in front and 300 lbs/in rear, sway bars, damper kit.
T3 Correct Touring 3 05-10 Mustang final drive #28288wordingneutralT3 Ford Mustang Coupe GT & Shelby GT 4.6L 05-10 adds permitted final drive ratios: 3.31, 3.55 or 3.73.
EP Request for Help for Datsun 1200 #27934inductionfasterHP Datsun 1200 carburetor choke size increases from 26mm to 30mm.
T3 2006 BMW E90 330i Sedan Classification #26663cars addedneutralBMW 330i 2006-2012 added to T3 with 2996cc engine, 3200 lbs minimum weight.
T3 Please Switch the Solstice GXP as Specified in T2, to T3 #27413cars added -50 lbsfasterPontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18 x 9.5 inches, Sky weight drops to 3200 lbs.
T3 Request to Classify all Mazda RX8 Models in T3/T4 #27606cars addedneutralMazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01.
T3 Request for 2005 Subaru STI Changes #27658tyres & wheels +50 lbs
T3 Request to Classify 2017 Ford Fiesta ST #27700cars addedneutralT3 adds 2017 Ford Fiesta ST, 1596cc, 2600 lbs minimum weight, 245 max tire, 17x9 wheels.
EP Request to List Mazda Miata Throttle Body Size #27907wordingneutralFP and EP Mazda Miata models standardized to 55mm throttle body diameter; brake spec clarified.
T3 Clarification of On-Board Fire System for T2 #27183wordingneutralT2 requires onboard fire system; T3 and T4 may have one per GCR 9.3.
T3 Mustang Ecoboost and GT Transmission #27439otherunclearT3 Ford Mustang EcoBoost 2015- gains three transmission gear ratio options.
T3 Nissan 350Z HR Engine Restrictor Plate/Minimum Weight #27442induction +50 lbsslowerT3 Nissan 350Z and 370Z HR engines: restrictor plate enlarged from 37mm to 42mm, weight increased 50-100 lbs.
T3 Request help for the GMX5 #27572tyres & wheelsneutralT3 Mazda MX-5 Global Cup Miata (2016-) tires now 215/610 R17 BF Goodrich G-Force Slick or wet; removes touring tire requirement.
T3 Request for 05-10 Mustang GT Suspension Upgrades #27777suspension & brakesfasterT3 05-10 Mustang GT 4.6L suspension upgrades allowed: tower braces, radiator, 500/300 lbs/in springs, sway bars, dampers, control arms, shocks, driveshaft.
T3 Please Update the BMW SpecE46 Rules #27781wordingneutralT3 BMW SpecE46 updates to SpecE46 rules Version 2.6 to 2.7, tire width to 225 maximum.
T3 Request for 02-03 WRX Spec Line Parts #27864weight -100 lbsfasterT3 Subaru WRX 02-05 minimum weight drops 100 lbs to 3250.
T3 T4 RX8 Classification Error #27902wordingneutralMazda RX-8 Base/R3 (04-12) reclassified in T3 and T4 to include Sport and GT variants.
T3 Request to add Toyota 86 GT to Spec Line #27910cars addedneutralToyota 86 GT (2017-) added to T3 and T4 Spec Line.
SRF3 SRF Rain / Brake Rule - BoD approved as follows #34958wordingneutralSRF rain and brake rule wording updated; supersedes GCR 9.3.32.B.2 effective 1/1/202 through 12/31/2024.
EP Re-organize Prep2 Cylinder Head Rules for Clarity & Consistency #27661wordingneutralEP, FP, HP cylinder head rules reorganized for clarity; no performance change.
SRF3 SRF Tire Warmer Rule #27622tyres & wheelsslowerSRF bans tire warmers and cooling methods other than natural air convection or conduction.
SRF3 SRF / SRF3 Nose Weight Reduction #27706weightfasterSRF front nose weight minimum reduced from 35 to 32 lbs.
SRF3 SRF / SRF3 Majors & Regional Class Updates #27723wordingneutralSRF3 reclassified as Spec Racer Ford 3 with 1.6L conversion; SRF2 becomes Regional Only Class.
T3 Request to add 2018 Subaru BRZ in T3 #27253cars addedneutralT3 Scion FR-S/Toyota 86 and Subaru BRZ year range extended from 13-17 to 13-20.
T3 Request Mazda NC MX-5 alternate transmission gear ratios #27155wordingneutralT3 Mazda NC MX-5 gains two alternate six-speed and one five-speed transmission gear ratio option.
EP Request bodywork for Austin Healey Bugeye Sprite MK1 #27106wordingneutralFP and HP Austin-Healey Sprite Mk I and MG Midget variants may replace rear bodywork aft of cockpit with stock-appearing alternate material components.
EP Request to classify the GMX5 2019 #27263wordingneutralEP Mazda MX-5 Global Cup classification year changes from 16-18 to 16-19.
EP level one susp. component rule #27270wordingneutralProduction suspension rule clarifies spindles, hubs, bushings, bearings, ball joints unrestricted.
EP Clarification of Carb Rules - Prep 1 #27300wordingneutralProduction carb rules clarified: carburetor options, fuel injection throttle body dimensions, and intake manifold restrictions reorganised and refined.
EP Clarification of Carb Rules - Prep 2 #27301wordingneutralEP, FP, HP carburetors clarified: jets, needles, metering rods, needle valves unrestricted; choke parts removable; permitted optional carburetors listed.
T3 Request spare tire/wheel clarification #27012wordingneutralT2-T4 spare tire/wheel rules clarified: removable covers can be removed with hardware and bracketry.
EP Request Miata Eligibility - 2003 #27121cars addedneutralEP Mazda MX-5/Miata eligibility years expanded from 1999-2002 to 1999-2005.
T3 Request guidance for 2014-2017 MK7 Volkswagen GTI #26866wordingneutralT3 Mk7 GTI gains R32 brake package, 4-piston Stoptech kit to 355mm, and ECS street shield allowance.
SRF3 SRF Dash Windscreen Kit #27028wordingneutralSRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102.
T3 Request BMW e36 M3 sway bar and links #26885suspension & brakesneutralT3 BMW E36 M3 96-00 allows alternate sway bars, 35mm front and 27mm rear.
SRF3 New SRF Sectional Nose Rule Addition #26914wordingneutralSRF3 nose assembly must use approved multi-piece design; no modifications allowed except as specified.
T3 Request to properly class base Porsche Cayman #26276cars addedneutral09-12 Porsche Cayman newly classified in T3 at 3150 lbs with 2900cc engine.
EP Allow Firewall Modification for Fitment of 13B into RX8 #26726wordingneutralEP Mazda RX-8 firewall modification allowed for 13B engine fitment in stock location.
SRF3 SRF Brakes and Shock Rule Changes #26629wordingneutralSRF3 brakes now allow Hawk Blue 9012 pads P/N 801993 only; shocks simplified to Penske P/N 280396 sealed assembly only, with optional SCCA Enterprises bump rubber P/N 280407 from 05/01/2020.
T3 Request to classify a 2019 Chevrolet Camaro LT-I4 Turbo 1LE #25731cars addedneutralT3 Chevrolet Camaro LT-I4 Turbo 1LE (2019-) classified with 1998 cc engine, 3450 lbs minimum weight, 245 max tire size.
T3 T3 Civic Si weight change #26294weightfasterT3 Honda Civic Si 2017- minimum weight reduced 100 lbs, to 2900.
T3 Class Civic Si 2017+ w/ alternate cage #26449cars addedneutralHonda Civic Si 2017+ with alternate cage classified in T3 at 3075 lbs minimum weight.
T3 Classify 2014-2017 MK7 Volkswagen GTI for T3 #26695cars addedneutralT3 classifies 2014-2017 Volkswagen GTI with 35 mm turbo inlet restrictor, 3080 lbs DSG, 3050 lbs standard.
EP Rollcenter Correction Clarification #25873suspension & brakesfasterEP, FP, HP clarified: tapered holes in ball joints now allowed for bolt conversion; wheel bearings and hubs unrestricted at any wheel.
EP Hardtops #26476wordingneutralEP open cars may now use aftermarket hardtops if they retain OEM appearance; specific model hardtop allowances removed.
T3 Request to allow E36 M3 in T3 prepared to BMWCCA I sport #25195cars addedneutralBMW E36 M3 (96-00) BMWCCA I Sport newly classified in T3 at 3100 lbs minimum weight.
EP Request for Competition Adjustment for 2nd Generation RX7 #25935weight -50 lbsfasterEP Mazda RX-7 12A and 13B (79-85) lose up to 80 lbs; 13B (86-91) loses up to 79 lbs.
T3 Request Mustang GT Limited Prep 2018 Classification #24431cars addedneutralT1-LP Ford Mustang GT 5.0L 2018+ classified at 3400 lbs with 65mm flat plate restrictor.
T3 Classify 2015+ WRX #25832cars addedneutralT3 Subaru WRX (2015-) classified at 3275 lbs with 35mm turbo inlet restrictor required.
T3 Correct Mazda MX-5 Hard Top Notes #26137wordingneutralT4 Mazda MX-5 Club (06-15) and (2016-), T3 MX-5 Cup and Miata (2016-) hardtop rules clarified; wording changes to permitted parts and specifications.
T3 Request to allow T3 06-15 Miata 17x8 wheels #26161tyres & wheelsfasterT3 Mazda MX-5 NC 06-15 wheel width increases from 17x7 to 17x8.
T3 Request T3 06-15 Miata header #26162aerofasterT3 Mazda MX-5 NC 06-15 now allows any aftermarket header.
T3 Request Pontiac GXP same allowances to Saturn Sky #26175aerofasterT3 Saturn Sky intercooler tolerance increases from 32mm to 35mm TIR; new calipers and springs permitted.
T3 Consider opening class rules to allow any thermostat #26187wordingneutralT2, T3, T4 now allow any thermostat serving only OE intent, previously restricted.
T3 2005-2009 Legacy GT/Spec B #26384cars addedneutralT3 Subaru Legacy GT/Spec B 05-09 newly classified with 2457cc, 18×9 wheels, 245 tires, 3300 lbs.
T3 Cap 2016 Mazda Miata year at 2018 #26388wordingneutralT3 and T4 Mazda MX-5 Miata eligibility capped at 2018 model year, effective 2019-03-01.
T3 Request correction on brake sizes #26170wordingneutralT3 Mazda Mazdaspeed3 07-09 front brake disc increases to 320mm vented, rear to 300mm solid.
T3 Errors, Omissions, and Updates (Various) #22414wordingneutralT4 Ford Fiesta ST years corrected to 14-; T4 Fiat 124/Abarth Edition years added 16-18; battery rule clarified.
T3 Request to update SpecE46 Appendix N. with 2019 Rules #25722wordingneutralT3 BMW SpecE46 rules reference updated from Appendix N to Version 2.6 Effective Jan 1, 2019.
T3 Request Alternative Nissan Brake Parts - 350Z #25747suspension & brakesneutralT3 Nissan 350Z Track/Touring/Standard/Nismo 03-08 permitted to use Nissan brake kit part number 41000-BRKIT.
T3 Add Clarification to Spec Car Classifications Vehicle Spec #25774wordingneutralT1-T3 spec cars receive clarifications on permitted modifications, documentation requirements, and rule conformance; no performance changes.
T3 Clarify Subframe Bushings Permitted for T2-T4 #25800wordingneutralT2-T4 subframe bushings may now be replaced with non-spherical bushings of any material.
T3 Additional weight adjustments for T3 cars T3 weight loss #25803weightfasterT3 field loses 50 lbs across 27 cars including Acura TL, BMW 335i, Camaro, Mustang, Miata, RX-8, 370Z, WRX.
T3 Request for Alternate EcoBoost Mustang Brakes #25813suspension & brakesslowerT3 Ford Mustang EcoBoost gains Ford Motorsports or Brembo brake kit options, +100 lb.
T3 Request to Add the FR-S/86 and BRZ Spec Lines to T3 #25888weightfasterT3 FR-S/86 and BRZ: wheels to 17x9, tires to 255, weight to 2750 lbs.
T3 Request to Clarify BMW SpecE46 Tire Verbiage #26027tyres & wheelsneutralT3 BMW SpecE46 now permits any DOT tire up to 225 width as alternate to spec tire.
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 EP" is the class's best as a share of EP'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 EP'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.