Lap times across years say as much about the weather as the class. % of P2 is each class's best lap as a share of P2's on the same day, so the conditions drop out: 100% is level, less is quicker, and a move in it is the class getting faster or slower against the field.
Closest to the field:P2 100.0% of P2 Jeff Shafer, Daytona International Speedway Runoffs 2015 race · AS 91.7% of P2 Gregory Eaton, Virginia International Raceway Runoffs 2022 race · STL 94.1% of P2 Danny Steyn, Virginia International Raceway Runoffs 2022 race · EP 110.3% of P2 Jesse Prather, Virginia International Raceway Runoffs 2019 race
P2ASSTLEPsolid race · dashed qualifying · slower is lower
P2ASSTLEPsolid race · dashed qualifying · each class's best lap as a share of P2's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
2:10.606Greg Gyann · fastest of 11 · top 5 within 5.3s+3.201s (+2.51%)
2:09.441Mike Reupert · fastest of 11 · top 5 within 4.2s+1.119s (+0.87%)
155.0Matt Strand+2.4 mph (+1.6%)
2:26.911Andrew McDermid · fastest of 8 · top 5 within 3.4s+0.119s (+0.08%)
2:28.471Andrew McDermid · fastest of 8 · top 5 within 2.4s-0.761s (-0.51%)
151.0Andrew McDermid-0.6 mph (-0.4%)
+19.030squal +16.305s
114.7%qual 112.5%
2:30.537Derek Ketchie · fastest of 16 · top 5 within 2.9s-1.528s (-1.00%)
2:30.657Danny Steyn · fastest of 16 · top 5 within 0.6s-1.470s (-0.97%)
134.8Mike Taylor+2.6 mph (+2.0%)
+21.216squal +19.931s
116.4%qual 115.3%
2:29.239Jon Brakke · fastest of 15 · top 5 within 5.2s+1.946s (+1.32%)
2:27.869Jon Brakke · fastest of 15 · top 5 within 5.2s-0.887s (-0.60%)
137.0Jon Brakke-3.8 mph (-2.7%)
+18.428squal +18.633s
114.2%qual 114.3%
38 rule changes (AS: 13, STL: 4, EP: 21)7 weight · 6 cars added · 5 engine · 5 induction · 2 aero · 1 suspension & brakes · 1 tyres & wheels · 8 wording · 3 other · AS Camaro 16+ Spec Line: 1LE front splitter kit permitted, belt tensioner and motor mount parts allowed, spark plug position defined. · AS class adds Pirelli P Zero Trofeo Track as permitted tyre option for competition. · AS class rear trailing arms no longer required to maintain stock length, only to locate rear axle. · AS Ford Mustang GT 4.6L 4-valve regains allowance, minimum weight 3200 lbs. · AS Ford Mustang Coupe GT 05-14 Gen3 Coyote minimum weight increases from 3100 to 3400 lbs. · HP Mini Cooper 02-06 compression ratio increases from 10.6 to 11.0:1. · 1996-2000 Honda Civic CX/DX/LX with D16Y7 engine newly classified in HP. · HP 1275 Midget/Sprite alternate intake manifold from MG-B now permitted; balance tube shortening and flange modification allowed. · HP Honda Civic DX/LX 92–95 wheels 13x7 to 15x7, weight 2420 to 2350 lbs. · STL removes Mazda MX-5 Cup entirely; renames Spec MX5 Challenge to Spec MX5; renames Global Cup to MX-5 Cup (16-18); removes Global Cup (2019). · AS GM LM7 5.3L must use full prep Holley carburetor as described in 9.1.6.D.c.1, not specifically 4776. · EP Honda S2000 gains permission to use Mugen hardtop P/N 0000-04-2312 or aftermarket equivalent. · STL, STU weight calculation procedure clarified: positive percentages added first, negative subtracted second, then fixed weights applied. · EP Mazda MX-5 94-97 front track widens to 1516 mm, rear to 1534 mm. · EP Triumph GT6 auto-type drivetrain choke size increases from 44mm to 45mm. · AS EFI engine build sheets add dry sump, header, camshaft, and timing chain tensioner options for LS, LT1, Ford, and Mopar engines. · AS LT1 Camaro engine build sheet added with full specs; LT1 weight 3200 lbs, GTO tire to 275, Mustang weight to 3525 lbs, oil catch tanks now required. · STL adds Mazda BP 1.6, 1600cc, minimum weight 2160 lbs. · AS Spec Lines reorganized for 2026; detailed chassis, engine, weight, wheelbase, tire and brake specifications moved to main rules and engine build sheets. · AS GM LM7 5.3L gains Edelbrock 71187 intake manifold, MSD 6014 ignition box, Holly 4776 carb option under full prep spec line. · AS Ford Mustang and Mercury Capri with Restricted Prep engines get 61 mm restrictor, down from 64 mm. · EP BMW 325i/is E30 fuel injection throttle body specified as 60mm diameter. · STL minimum weights increase across all engine sizes, 1300cc to 1850cc up to 195–250 lbs. · AS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft. · EP Triumph TR2–TR4A may use 5-speed gearbox without overdrive; Weber carburetors and weight reference deleted. · EP BMW Z3 2.5L and other models get smaller restrictors, 50mm to 55mm, and Z3 2.5L weight rises 50 to 78 lbs. · AS Cadillac CTS-V 04-07 Restricted Prep minimum weight drops to 3400 lbs. · EP Nissan 280Z minimum weight lowered to 2400 lbs, 2460 lbs with *, 2520 lbs with **. · EP Mazda MX-5 1.8L 90-97 minimum weight reduced to 2125 lbs. · HP Spec Lines Austin-Healey Sprite/Midget 1098cc minimum weight drops to 1550 lbs. · HP Volvo 142 P-1800 engine gains compression ratio limit 12.0:1 and valve lift limit .425 inch. · HP Mini DOHC 1.6 valve lift limit drops to .390" from .450". · FP and HP Volkswagen Rabbit descriptions updated to clarify Cabriolet body style inclusion. · EP, FP, HP: rear drum-to-disc brake conversion clarified; rotors solid, diameter limited to largest front rotor permitted. · EP Ford Mustang 94-98 fuel injected throttle body inside diameter set to 60. · HP Plymouth Arrow gains 4 or 5 speed transmission option specification. · Appendix G.2.3 clarifies rim width and diameter are absolute maximums; wording corrected from 'is' to 'are'. · EP, FP, HP throttle body inside dimensions and butterfly now allow +/-.25mm tolerance from stock.showhide
AS 2016+ Camaro Spec Line Full Prep #39646otheraddedAS Camaro 16+ Spec Line: 1LE front splitter kit permitted, belt tensioner and motor mount parts allowed, spark plug position defined.
AS Consideration of Pirelli P Zero Trofeo Track for AS Competition #40495tyres & wheelsaddedtyres & wheelsAS class adds Pirelli P Zero Trofeo Track as permitted tyre option for competition.
AS Change in 9.1.6.D.4.d.5 in Suspension Mounting Points #40094suspension & brakesfastersuspension & brakesAS class rear trailing arms no longer required to maintain stock length, only to locate rear axle.
AS Re-Add 4.6L 4v 96-04 Mustang Cobra #40239cars addedaddedAS Ford Mustang GT 4.6L 4-valve regains allowance, minimum weight 3200 lbs.
AS Errors and Omissions #40532weightslowerweightAS Ford Mustang Coupe GT 05-14 Gen3 Coyote minimum weight increases from 3100 to 3400 lbs.
EP Mini Cooper Compression Ratio #40517enginefasterengineHP Mini Cooper 02-06 compression ratio increases from 10.6 to 11.0:1.
EP 1996-2000 Honda Civic (CX, DX, VP, LX) with Engine Code D16Y7 #40322cars addedadded1996-2000 Honda Civic CX/DX/LX with D16Y7 engine newly classified in HP.
EP 1275 Midget/Sprit Alternate intake manifold E/O #40370inductionaddedinductionHP 1275 Midget/Sprite alternate intake manifold from MG-B now permitted; balance tube shortening and flange modification allowed.
EP HP Honda Civic (92-95) #40464weight -70 lbsfasterweightHP Honda Civic DX/LX 92–95 wheels 13x7 to 15x7, weight 2420 to 2350 lbs.
STL Spec Line Clean Up #40344cars addedremovedcars addedSTL removes Mazda MX-5 Cup entirely; renames Spec MX5 Challenge to Spec MX5; renames Global Cup to MX-5 Cup (16-18); removes Global Cup (2019).
AS Clarification for LM7 Holley Carburetor #40167wordingwordingAS GM LM7 5.3L must use full prep Holley carburetor as described in 9.1.6.D.c.1, not specifically 4776.
EP Honda S2000 Hardtop #40138aeroaddedaeroEP Honda S2000 gains permission to use Mugen hardtop P/N 0000-04-2312 or aftermarket equivalent.
STL Calculating Weight #40224wordingwordingSTL, STU weight calculation procedure clarified: positive percentages added first, negative subtracted second, then fixed weights applied.
EP Miata track width - errors and omissions #39976aerofasteraeroEP Mazda MX-5 94-97 front track widens to 1516 mm, rear to 1534 mm.
EP Triumph GT6 Spec Change. #40098inductionfasterinductionEP Triumph GT6 auto-type drivetrain choke size increases from 44mm to 45mm.
AS Header Information Update for EFI Engine Build Sheets #39886engineaddedengineAS EFI engine build sheets add dry sump, header, camshaft, and timing chain tensioner options for LS, LT1, Ford, and Mopar engines.
AS Errors and Omissions #39933otherfasterAS LT1 Camaro engine build sheet added with full specs; LT1 weight 3200 lbs, GTO tire to 275, Mustang weight to 3525 lbs, oil catch tanks now required.
AS Re-Organization of AS Spec lines for 2026 #39887wordingwordingAS Spec Lines reorganized for 2026; detailed chassis, engine, weight, wheelbase, tire and brake specifications moved to main rules and engine build sheets.
AS Edelbrock manifold (& timing kit) to Chevy LS Spec Lines Request #39055cars addedaddedAS GM LM7 5.3L gains Edelbrock 71187 intake manifold, MSD 6014 ignition box, Holly 4776 carb option under full prep spec line.
AS Restrictor Plate Change for Gen 2 Ford Coyote Engine #39501inductionslowerinductionAS Ford Mustang and Mercury Capri with Restricted Prep engines get 61 mm restrictor, down from 64 mm.
EP Request to Update E30 BMW Throttle Body Diameter Verbiage #39363wordingwordingEP BMW 325i/is E30 fuel injection throttle body specified as 60mm diameter.
STL Weight adjustment for STL #39579weightslowerweightSTL minimum weights increase across all engine sizes, 1300cc to 1850cc up to 195–250 lbs.
AS 1994 Mustang Spec Line Request #39104engineaddedengineAS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft.
EP TR2 Notes E&O #39180wordingwordingEP Triumph TR2–TR4A may use 5-speed gearbox without overdrive; Weber carburetors and weight reference deleted.
EP Balance of Power #39187induction +50 lbsslowerinductionEP BMW Z3 2.5L and other models get smaller restrictors, 50mm to 55mm, and Z3 2.5L weight rises 50 to 78 lbs.
AS Cadillac CTS-V BOP Weight Change #38640weight -50 lbsfasterweightAS Cadillac CTS-V 04-07 Restricted Prep minimum weight drops to 3400 lbs.
EP Please Lower Weight of 280Z #38871weight -160 lbsfasterweightEP Nissan 280Z minimum weight lowered to 2400 lbs, 2460 lbs with *, 2520 lbs with **.
EP Miata Weight Adjustment Follow Up #38949weight -25 lbsfasterweightEP Mazda MX-5 1.8L 90-97 minimum weight reduced to 2125 lbs.
EP Weight Break for 1098 Midget / Sprite #38970weight -80 lbsfasterweightHP Spec Lines Austin-Healey Sprite/Midget 1098cc minimum weight drops to 1550 lbs.
EP HP Volvo 142 spec omission #38994engineslowerengineHP Volvo 142 P-1800 engine gains compression ratio limit 12.0:1 and valve lift limit .425 inch.
EP HP Mini DOHC 1.6 #38996engineslowerengineHP Mini DOHC 1.6 valve lift limit drops to .390" from .450".
EP Add to Rabbit description #39019wordingwordingFP and HP Volkswagen Rabbit descriptions updated to clarify Cabriolet body style inclusion.
EP Clean-up 9.1.5.E.7e #39025otherotherEP, FP, HP: rear drum-to-disc brake conversion clarified; rotors solid, diameter limited to largest front rotor permitted.
EP Add TB size to Ford Mustang (94-98) Spec Line #39130inductionaddedinductionEP Ford Mustang 94-98 fuel injected throttle body inside diameter set to 60.
EP HP Plymouth Arrow spec omission #38995cars addedaddedHP Plymouth Arrow gains 4 or 5 speed transmission option specification.
EP Add Wheel Diameter to Appendix G #39008wordingwordingAppendix G.2.3 clarifies rim width and diameter are absolute maximums; wording corrected from 'is' to 'are'.
EP Add TB ID tolerance to general Prod rules #39009wordingaddedEP, FP, HP throttle body inside dimensions and butterfly now allow +/-.25mm tolerance from stock.
2:26.792Andrew McDermid · fastest of 11 · top 5 within 3.9s+0.214s (+0.15%)
2:29.232Gregory Eaton · fastest of 10 · top 5 within 4.0s+2.803s (+1.91%)
151.5Andrew McDermid+1.9 mph (+1.3%)
2:32.065Jose Osiris Pena · fastest of 14 · top 5 within 3.4s+2.002s (+1.33%)
2:32.127Jose Osiris Pena · fastest of 13 · top 5 within 2.4s+1.882s (+1.25%)
132.2Jon Sewell-2.1 mph (-1.5%)
2:27.293Jon Brakke · fastest of 21 · top 5 within 2.1s+0.490s (+0.33%)
2:28.756Tyler Ladd · fastest of 19 · top 5 within 1.9s+0.887s (+0.60%)
140.8Jon Brakke+0.1 mph (+0.1%)
29 rule changes (P2: 1, AS: 11, STL: 3, EP: 14)9 weight · 5 induction · 4 engine · 3 cars added · 5 wording · 3 other · Lotus Evora GT4 minimum weight drops to 2700 lbs; Elise Cup R to 2250 lbs; Elise SC and Exige SC to 2450–2550 lbs. · AS Ford Mustang GT 5.0 2018- minimum weight reduced to 3525 lbs. · EP BMW Z4 03-05 gains 52mm flat plate intake restrictor. · EP Fiat 124 Spider Competition 1600 and 2000 minimum weight drops 50 lbs to 2000; carburetors now allow 36mm chokes instead of 34mm. · AS Ford Mustang GT 05-14 Restricted Prep Engine gains additional gear ratio option: 3.66, 2.43, 1.69, 1.32, 1.00, .65. · HP Fiat X-1/9 and Bertone 1500 minimum weights reduced to 1740 lbs, 1784 lbs, 1827 lbs; 1300 models to 1600, 1640, 1680 lbs; additional 1300 and 1500 specs to 2010, 1900 lbs. · AS Ford Mustang GT 5.0L 15-17 flat plate restrictor reduces from 67mm to 64mm. · AS LS1/LS6 intakes added for 5.3L truck engine: part numbers 12561269 and 88894095. · STL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1; mandatory component spec list removed, alternative tires only allowed. · AS Flotek head value seat cutting dimensions figure updated for consistency. · AS class notes cleaned: fuel cell and ECM specifications removed from multiple Camaro, Firebird, Challenger and Mustang variants. · Chevrolet Spark 16-22 classified in HP Pre at 1850 lbs base, 1896 lbs modified, 1943 lbs. · HP Ford Festiva 88-93 minimum weight lowered to 1600 lbs, competition weight to 1640, prepared weight to 1680; compression ratio raised to 11.0:1. · AS removes 'Any ECM maybe used' note from five Cadillac and Chevrolet/Pontiac V8 Restricted Prep models. · EP BMW Z3 2.5L, Z3 2.8L, 328i E36/E46, 325i E36/E46 intake restrictors reduced 4mm each, to 52–58mm. · EP, FP, HP may use any interior or exterior mirror meeting rule 9.3.36. · EP Honda S2000 1997cc minimum weight drops 75 lbs to 2375; 2157cc drops 60 lbs to 2450. · EP Mazda MX-5 Miata 99-05 minimum weight reduced to 2100 lbs, 2153 lbs with power, 2205 lbs modified. · EP BMW models now require flat plate intake restrictors: Z3 2.5L 52mm, Z3 2.8L 55mm, 328i E36 58mm, 328i/ci E46 58mm, 325i E46 56mm, 325i E36 56mm, 325is M-Technic 56mm. · AS Ford Mustang and Cobra Coyote engine restrictor increases to 80mm from 67mm or 64mm. · AS Mustang GT 05-14 Restricted loses 300 lbs engine; 15-17 and 2018+ models lose 61mm and 60mm restrictors respectively. · AS class: multiple American muscle cars gain additional allowed gear ratio options across model years and prep levels. · AS LS-engine cars gain ECU freedom: CTS-V, Camaro, Firebird (70–02) and Camaro SS may use any ECM. · EP BMW 325i/is E30 84-91 weight reduced to 2150 lbs base, 2204 lbs with turbo, 2258 lbs supercharged. · EP Triumph GT6 switches to three Weber 40 DCOE carburetors with 28mm chokes, weight rises to 1990 lbs. · P2 2000 cc Pinto engine car minimum weight set to 1335 lbs. · STL STU Mazda Miata alternate front hubs Mazda Motorsports Development Part #0000-04-5HUB-S1 approved. · HP 1275 Spridget compression ratio raised to 12.0:1; 1098cc also raised to 12.0:1. · EP Miata 1.6L, 1.8L 90–97, and 94–97 track width corrected to 1516/1534 mm (59.7/60.4 in.) front and rear.showhide
STL Lotus Weight Reduction #38772weight -50 lbsfasterweightLotus Evora GT4 minimum weight drops to 2700 lbs; Elise Cup R to 2250 lbs; Elise SC and Exige SC to 2450–2550 lbs.
AS RE: Previous Letter 37695 Update #38245weight -75 lbsfasterweightAS Ford Mustang GT 5.0 2018- minimum weight reduced to 3525 lbs.
EP BMW Z4 update #38490inductionslowerinductionEP BMW Z4 03-05 gains 52mm flat plate intake restrictor.
EP EP Fiat 124 Spider Competition Adjustment Request #38498weight -50 lbsfasterweightEP Fiat 124 Spider Competition 1600 and 2000 minimum weight drops 50 lbs to 2000; carburetors now allow 36mm chokes instead of 34mm.
AS Errors and Omissions #38234otheraddedAS Ford Mustang GT 05-14 Restricted Prep Engine gains additional gear ratio option: 3.66, 2.43, 1.69, 1.32, 1.00, .65.
EP Base Weight Adjustment for H-Production X1/9 Spec Lines #38255weight -50 lbsfasterweightHP Fiat X-1/9 and Bertone 1500 minimum weights reduced to 1740 lbs, 1784 lbs, 1827 lbs; 1300 models to 1600, 1640, 1680 lbs; additional 1300 and 1500 specs to 2010, 1900 lbs.
AS Errors and Omission #38055inductionslowerinductionAS Ford Mustang GT 5.0L 15-17 flat plate restrictor reduces from 67mm to 64mm.
AS Request to Add LS1/LS6 Intakes for 5.3L Truck Engine EnO #38197cars addedaddedAS LS1/LS6 intakes added for 5.3L truck engine: part numbers 12561269 and 88894095.
STL E&O: SMX Allowance in STL #37945wordingunclearSTL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1; mandatory component spec list removed, alternative tires only allowed.
AS Flotek Head Plunge Cut Inconsistencies #37502wordingwordingAS Flotek head value seat cutting dimensions figure updated for consistency.
AS Notes clean up #37693wordingwordingAS class notes cleaned: fuel cell and ECM specifications removed from multiple Camaro, Firebird, Challenger and Mustang variants.
EP Request for Classification of Chevrolet Spark #37755cars addedaddedChevrolet Spark 16-22 classified in HP Pre at 1850 lbs base, 1896 lbs modified, 1943 lbs.
EP Request to Lower Ford Festiva Minimum Weight to 1600 LBS #37939weight -100 lbsfasterweightHP Ford Festiva 88-93 minimum weight lowered to 1600 lbs, competition weight to 1640, prepared weight to 1680; compression ratio raised to 11.0:1.
AS Race memo #37902wordingwordingAS removes 'Any ECM maybe used' note from five Cadillac and Chevrolet/Pontiac V8 Restricted Prep models.
EP Request Competition Adjustment to BMW Z3 2.5L #37120inductionslowerinductionEP BMW Z3 2.5L, Z3 2.8L, 328i E36/E46, 325i E36/E46 intake restrictors reduced 4mm each, to 52–58mm.
EP Interpretation of Production Rules on Mirrors #37235wordingaddedEP, FP, HP may use any interior or exterior mirror meeting rule 9.3.36.
EP Weight Reduction for Honda S2000 #37466weightfasterweightEP Honda S2000 1997cc minimum weight drops 75 lbs to 2375; 2157cc drops 60 lbs to 2450.
EP Mazda 1999 Miata 1.8L #37488weight -50 lbsfasterweightEP Mazda MX-5 Miata 99-05 minimum weight reduced to 2100 lbs, 2153 lbs with power, 2205 lbs modified.
EP Effective date for Jan 2025 GCR updates #37654inductionslowerinductionEP BMW models now require flat plate intake restrictors: Z3 2.5L 52mm, Z3 2.8L 55mm, 328i E36 58mm, 328i/ci E46 58mm, 325i E46 56mm, 325i E36 56mm, 325is M-Technic 56mm.
AS Increase Coyote Engine Restrictor to 80mm #36177enginefasterengineAS Ford Mustang and Cobra Coyote engine restrictor increases to 80mm from 67mm or 64mm.
AS Performance Pack for 2015+ Mustang #36867enginefasterengineAS Mustang GT 05-14 Restricted loses 300 lbs engine; 15-17 and 2018+ models lose 61mm and 60mm restrictors respectively.
AS Gear Ratios #37131otheraddedAS class: multiple American muscle cars gain additional allowed gear ratio options across model years and prep levels.
AS ECU specs for LS engine #37208engineaddedengineAS LS-engine cars gain ECU freedom: CTS-V, Camaro, Firebird (70–02) and Camaro SS may use any ECM.
EP Request to Reduce Weight of BMW 325i/is E30 (84-91) Spec Line #37119weight -50 lbsfasterweightEP BMW 325i/is E30 84-91 weight reduced to 2150 lbs base, 2204 lbs with turbo, 2258 lbs supercharged.
EP Triumph GT6 Adjustments #37112inductionfasterinductionEP Triumph GT6 switches to three Weber 40 DCOE carburetors with 28mm chokes, weight rises to 1990 lbs.
P2 2000 cc Pinto Engine Car Weight #37187weightslowerweightP2 2000 cc Pinto engine car minimum weight set to 1335 lbs.
STL Request to Remove Miata Hubs from General category #37138cars addedaddedSTL STU Mazda Miata alternate front hubs Mazda Motorsports Development Part #0000-04-5HUB-S1 approved.
EP 1275 HP Spridget Level 2 Only #36518enginefasterengineHP 1275 Spridget compression ratio raised to 12.0:1; 1098cc also raised to 12.0:1.
EP NA Miata Track Width Correction #36902otherotherEP Miata 1.6L, 1.8L 90–97, and 94–97 track width corrected to 1516/1534 mm (59.7/60.4 in.) front and rear.
2:07.405Bart Wolf · fastest of 14 · top 5 within 3.0s-1.109s (-0.86%)
2:08.322Bart Wolf · fastest of 13 · top 5 within 0.6s-1.471s (-1.13%)
152.5Lucian Pancea-0.6 mph (-0.4%)
2:26.578Gregory Eaton · fastest of 18 · top 5 within 2.6s-0.467s (-0.32%)
2:26.429Gregory Eaton · fastest of 18 · top 5 within 2.5s-1.239s (-0.84%)
149.6Gregory Eaton+0.4 mph (+0.3%)
+18.107squal +19.173s
114.1%qual 115.0%
2:30.063Joe Moser · fastest of 18 · top 5 within 3.7s-1.357s (-0.90%)
2:30.245Joe Moser · fastest of 16 · top 5 within 4.2s-1.870s (-1.23%)
134.3Joe Moser+1.3 mph (+1.0%)
+21.923squal +22.658s
117.1%qual 117.8%
2:26.803Tyler Ladd · fastest of 16 · top 5 within 4.1s-0.519s (-0.35%)
2:27.869Tyler Ladd · fastest of 16 · top 5 within 3.6s-1.178s (-0.79%)
140.7Bill Miller-1.0 mph (-0.7%)
+19.547squal +19.398s
115.2%qual 115.2%
34 rule changes (P2: 5, AS: 11, STL: 4, EP: 14)8 cars added · 8 weight · 4 engine · 1 aero · 1 induction · 1 removed · 1 tyres & wheels · 6 wording · 4 other · AS Mustang GT 05-14 Restricted Prep and 2018- gain alternate transmission ratio options. · HP Volkswagen Golf and Jetta 85-92 track correction: front 1537 mm (60.5 in.), rear 1529 mm (60.2 in.). · AS adds 2018-23 Ford Mustang GT 5.0L at 3600 lbs, 275 tire, 60mm restrictor, optional Brembo front brakes. · Nissan 300ZX 84–89 added to EP, 2550–2678 lbs, 2960 cc SOHC, fuel injection, 12.0:1 compression, 0.500" valve lift limit. · Mazda RX-7 92-97 added to EP Prep as Level 2 rotary 13B 6-port, 2200–2310 lbs, carb or fuel injection, 42 mm choke. · EP Mazda RX-8 (04-11) alternate spec line removed; single spec line retained. · AS Chevrolet Camaro 1LE (2016-) added with 3600 lbs minimum weight, 275 tires, 60mm restrictor, 345/338mm brakes. · AS Chevrolet/Pontiac Camaro & Firebird 82–92 5.7L LS1 classified: 3200 lbs, 13.1×1.27 disc brakes, 17 in max wheel, 65 mm restrictor, SLP intake lid permitted. · AS Chevrolet Camaro, Firebird, and Ford Mustang now permit Flo Tek cylinder heads in multiple generations. · P2 Spec Line E engine notes clarify oil system, ECU, and exhaust remain unrestricted; wording only. · P2 FIA Group CN notes clarify V de V European Proto Endurance Challenge bodywork, rear diffuser, wing, wheels, assisted shifting allowed; regulations link provided. · AS Camaro, Firebird 93-02 and GTO 04-06 add approved LS1 connecting rod part numbers to Notes. · AS Cadillac CTS-V, Chevy Camaro SS V8, Dodge Challenger, Ford Mustang GT 5.0L, Pontiac GTO allowed 11" wheels until 3/1/25. · Chevrolet Camaro, Pontiac Firebird 70–81 Full Prep classified in AS at 3400–3600 lbs with 108.0 wheelbase, specific head castings, and suspension modifications permitted. · AS class adds fuel cell location notes to multiple Cadillac, Chevrolet, Dodge and Ford models: cells within 24 inches of standard tank. · Chevrolet Camaro 6th gen Full Prep added to AS class at 3400 lbs base or 3600 lbs with built engine. · AS class: Ford Mustang GT 05-14 Restricted prep added; Cadillac CTS-V 04-07 to 3450 lbs; Camaro/Firebird variants reconfigured with weight and notes changes; Dodge Challenger 08-20 restrictor 76mm to 80mm; Ford Mustang variants updated wei… · HP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve 83-88, Scirocco 1588. · HP Honda Civic 1.5 1988-91 minimum weight drops 70 lbs to 2175; also 2-speed and 3-speed minimums cut 72 and 73 lbs. · STL and STU now permit electric power steering pumps, OEM electric-assisted steering, or column-mounted electric steering assist systems. · STL normally aspirated minimum weights reduced: 1900cc to 2540 lbs, 1950cc to 2583 lbs, 2000cc to 2625 lbs; short-wheelbase FWD adds 1.25%; Honda B16/B17/B18C1 throttle to 51mm, B18C Type R and Mazda MZR to 50mm. · STL Mazda 12A: 5th and 6th intake port actuators and valves may no longer be removed or disabled. · EP BMW Z3 2.5L minimum weight increased to 2500 lbs, 2563 lbs with power adder, 2625 lbs with two power adders. · EP Mazda MX-5 1.8L (90-97) minimum weight cut to 2150 lbs; (94-97) variants to 2000, 2050, 2100 lbs. · EP Triumph GT6 dual 1.75-inch carburetors weight rises to 1940 lbs; triple Weber 40 DCOE option added at 1990 lbs. · 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. · EP Porsche 944/924S 2.5L and 2.7L minimum weights corrected: 2479cc to 2306–2363 lbs, 2681cc to 2358–2415 lbs. · P2 AMAC and related cars: clarified B.1 modified engine range to 2008 and older stock engines only, with 38mm restrictor and 1025 lbs minimum weight. · P2 Suzuki GSX-R1000 engine: 2007–2008 crankcase 11300-21860 may be replaced with 2016–2019 GSX-S1000 part 11301-04840. · STL 79-85 RX7 12A now allows auto-type 2 bbl carburetor with 42mm choke on dual-y manifold, not just stock Nikki. · EP Porsche 944/924S combines 2.5L and 2.7L variants (83-89), raises weight to 2250–2415 lbs, allows 2681cc displacement. · EP Triumph GT6 minimum weight drops to 1800 lbs. · P2 Table 1 engine date ranges clarified: Stock Engine replaced with specific marques Suzuki, Yamaha, Honda, BMW for 2009-newer and 2008-older rows.showhide
AS Mustang transmission ratios #36662otheraddedAS Mustang GT 05-14 Restricted Prep and 2018- gain alternate transmission ratio options.
EP Errant entry in HP production line item #36231wordingwordingHP Volkswagen Golf and Jetta 85-92 track correction: front 1537 mm (60.5 in.), rear 1529 mm (60.2 in.).
AS Request for Classification of 2018-2023 mustang In #35764cars addedaddedAS adds 2018-23 Ford Mustang GT 5.0L at 3600 lbs, 275 tire, 60mm restrictor, optional Brembo front brakes.
EP NIssan 300ZX Z31 to EP #35830cars addedaddedNissan 300ZX 84–89 added to EP, 2550–2678 lbs, 2960 cc SOHC, fuel injection, 12.0:1 compression, 0.500" valve lift limit.
EP RX7 1993 and Up Request In EP Spec Lines, classify #36031cars addedaddedMazda RX-7 92-97 added to EP Prep as Level 2 rotary 13B 6-port, 2200–2310 lbs, carb or fuel injection, 42 mm choke.
EP Clean-up Multiple EP RX-8 Spec Lines In EP #36156cars addedremovedcars addedEP Mazda RX-8 (04-11) alternate spec line removed; single spec line retained.
AS 6th gen Camaro limited prep #35733cars addedaddedAS Chevrolet Camaro 1LE (2016-) added with 3600 lbs minimum weight, 275 tires, 60mm restrictor, 345/338mm brakes.
AS Chevrolet/Pontiac Camaro & Firebird (82-92) 5.7L V8 LS1 Alum BLK #35825cars addedaddedAS Chevrolet/Pontiac Camaro & Firebird 82–92 5.7L LS1 classified: 3200 lbs, 13.1×1.27 disc brakes, 17 in max wheel, 65 mm restrictor, SLP intake lid permitted.
AS Full Prep Head #35891engineaddedengineAS Chevrolet Camaro, Firebird, and Ford Mustang now permit Flo Tek cylinder heads in multiple generations.
P2 CN Spec ECU #35835wordingwordingP2 Spec Line E engine notes clarify oil system, ECU, and exhaust remain unrestricted; wording only.
P2 E&O - Correct FIA Group CN spec line notes #35900wordingwordingP2 FIA Group CN notes clarify V de V European Proto Endurance Challenge bodywork, rear diffuser, wing, wheels, assisted shifting allowed; regulations link provided.
AS Restricted Prep Aftermarket Parts Request #35682otheraddedAS Camaro, Firebird 93-02 and GTO 04-06 add approved LS1 connecting rod part numbers to Notes.
AS Allowance of 11 #35824tyres & wheelsfastertyres & wheelsAS Cadillac CTS-V, Chevy Camaro SS V8, Dodge Challenger, Ford Mustang GT 5.0L, Pontiac GTO allowed 11" wheels until 3/1/25.
AS Request to Classify 1970-1981 Camaro and Firebird in AS #33659cars addedaddedChevrolet Camaro, Pontiac Firebird 70–81 Full Prep classified in AS at 3400–3600 lbs with 108.0 wheelbase, specific head castings, and suspension modifications permitted.
AS Fuel Cell 12 #34194otheraddedAS class adds fuel cell location notes to multiple Cadillac, Chevrolet, Dodge and Ford models: cells within 24 inches of standard tank.
AS Please Classify the 6th Gen Into AS. #35448cars addedaddedChevrolet Camaro 6th gen Full Prep added to AS class at 3400 lbs base or 3600 lbs with built engine.
AS spec lines #35713otherunclearAS class: Ford Mustang GT 05-14 Restricted prep added; Cadillac CTS-V 04-07 to 3450 lbs; Camaro/Firebird variants reconfigured with weight and notes changes; Dodge Challenger 08-20 restrictor 76mm to 80mm; Ford Mustang variants updated wei…
EP GCR Correction - Redundant HP Spec Lines #35623removedremovedHP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve 83-88, Scirocco 1588.
EP Update 1988-1991 Civic to Match 1988-1991 CRX #35399weightfasterweightHP Honda Civic 1.5 1988-91 minimum weight drops 70 lbs to 2175; also 2-speed and 3-speed minimums cut 72 and 73 lbs.
STL ST Electric-Assisted Steering Systems #35066aeroaddedaeroSTL and STU now permit electric power steering pumps, OEM electric-assisted steering, or column-mounted electric steering assist systems.
STL BOP Adjustments #35112weightfasterweightSTL normally aspirated minimum weights reduced: 1900cc to 2540 lbs, 1950cc to 2583 lbs, 2000cc to 2625 lbs; short-wheelbase FWD adds 1.25%; Honda B16/B17/B18C1 throttle to 51mm, B18C Type R and Mazda MZR to 50mm.
STL Mazda 12A #35320engineremovedengineSTL Mazda 12A: 5th and 6th intake port actuators and valves may no longer be removed or disabled.
EP Request to Review Z3 2.5 Spec Line #35073weight +50 lbsslowerweightEP BMW Z3 2.5L minimum weight increased to 2500 lbs, 2563 lbs with power adder, 2625 lbs with two power adders.
EP Miata Alternate Head #35253weight -50 lbsfasterweightEP Mazda MX-5 1.8L (90-97) minimum weight cut to 2150 lbs; (94-97) variants to 2000, 2050, 2100 lbs.
EP Triumph GT6 Adjustments #35255weightslowerweightEP Triumph GT6 dual 1.75-inch carburetors weight rises to 1940 lbs; triple Weber 40 DCOE option added at 1990 lbs.
EP Honda S2000 throttle body #35272inductionfasterinductionEP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm.
EP Correction within Triumph TR8 Spec Line #35315wordingwordingEP Triumph TR8 dry sump allowance moved from Carburetor line to Notes.
EP Correction to EP 924S/944 Spec Line #35317weightweightEP Porsche 944/924S 2.5L and 2.7L minimum weights corrected: 2479cc to 2306–2363 lbs, 2681cc to 2358–2415 lbs.
P2 E&O - Clarify B.1 modified engine range in AMAC spec lines #35225wordingwordingP2 AMAC and related cars: clarified B.1 modified engine range to 2008 and older stock engines only, with 38mm restrictor and 1025 lbs minimum weight.
P2 Replacement Engine Crankcase for 07/08 Suzuki GSX-R1000 Engines #35340engineaddedengineP2 Suzuki GSX-R1000 engine: 2007–2008 crankcase 11300-21860 may be replaced with 2016–2019 GSX-S1000 part 11301-04840.
STL Alternate Carburetor Request for 79-85 RX7 12a #35181engineaddedengineSTL 79-85 RX7 12A now allows auto-type 2 bbl carburetor with 42mm choke on dual-y manifold, not just stock Nikki.
EP Porsche 944/924S Rule Change Request #35002weightslowerweightEP Porsche 944/924S combines 2.5L and 2.7L variants (83-89), raises weight to 2250–2415 lbs, allows 2681cc displacement.
EP Triumph GT6 Adjustments #35054weight -30 lbsfasterweightEP Triumph GT6 minimum weight drops to 1800 lbs.
P2 Correct Table 1 for Engine Date Range Specifications #35182wordingwordingP2 Table 1 engine date ranges clarified: Stock Engine replaced with specific marques Suzuki, Yamaha, Honda, BMW for 2009-newer and 2008-older rows.
1:48.590Greg Gyann · fastest of 12 · top 5 within 1.7s+1.024s (+0.95%)
1:48.829Lucian Pancea · fastest of 11 · top 5 within 0.9s-27.005s (-19.88%)
150.9Lucian Pancea-0.2 mph (-0.2%)
2:03.082Daniel Richardson · fastest of 11 · top 5 within 2.2s+0.920s (+0.75%)
2:04.120Gregory Eaton · fastest of 9 · top 5 within 3.0s-0.458s (-0.37%)
154.6James Jost+3.7 mph (+2.5%)
+15.291squal +14.492s
114.1%qual 113.3%
2:05.779Danny Steyn · fastest of 22 · top 5 within 3.4s+0.305s (+0.24%)
2:06.682Joe Moser · fastest of 20 · top 5 within 1.5s-1.150s (-0.90%)
131.8Danny Steyn+0.1 mph (+0.1%)
+17.853squal +17.189s
116.4%qual 115.8%
2:03.215John Hainsworth · fastest of 24 · top 5 within 4.3s+0.889s (+0.73%)
2:04.050Greg Ira · fastest of 22 · top 5 within 5.3s-26.805s (-17.77%)
144.6Greg Ira+3.1 mph (+2.2%)
+15.221squal +14.625s
114.0%qual 113.5%
27 rule changes (P2: 8, AS: 4, STL: 2, EP: 13)4 cars added · 4 engine · 1 induction · 1 removed · 1 suspension & brakes · 1 tyres & wheels · 1 weight · 11 wording · 3 other · EP Triumph TR8 78-81 removes allowance for alternate front hubs of same external dimensions and weight. · EP Triumph GT6 carburetor type changes from SU or Stromberg to Auto-type, quantity two 1.5 inch. · EP Triumph GT6 Brakes Alt. now permits TR-6 standard or alternate calipers and discs. · AS crate motor part number specification clarified; both CT400 P/N-19370604 and 19370604 engine assemblies permitted for GM vehicles. · AS Ford Mustang GT 5.0L (15-17) Restricted maximum wheel diameter increases to 19.0 inches. · AS Dodge Challenger 5.7L/6.1L/6.4L V8 allows alternate front upper control arms; SPC-66045 spec part removed. · AS Dodge Challenger 5.7L/6.1L/6.4L V8 now allows alternate front brake calipers with adaptor brackets for component compatibility. · FP and HP Sprite and Spitfire 1500 intake valve size corrected to 36.6 mm, removing prior decimal specifications. · EP Porsche 914-6 2.0L intake valve increased to 2.0 mm, exhaust valve corrected to 38.0 mm. · STL ITA and ITS RX7, and ITS/ITA/ITB/ITC 1985+ models clarified to require tires per 9.1.4.2. · P2 minimum side body height must equal front axle centerline height, viewed from side. · P2 closed cockpit single seat cars now prohibited unless Table 1 spec line permits. · EP BMW Z3 2.5L flat plate intake restrictor reduced from 58mm to 56mm, both throttle bodies. · P2 engine table spec line B.1 redundant effective date language removed and table updated. · P2 motorcycle restrictor reduced 35mm to 34mm for 2011+ Kawasaki; minimum weights increased to 1100 lbs for 2009+ engines; cockpit length corrected to 23.622 inches. · EP 79-85 RX-7 brake hub and rotor spec removed; 13B rotor housing and housing options now permitted. · EP Nissan 280Z carburetor option clarified: Hitachi-SU 1bbl 46mm throttle bores or fuel injection permitted. · EP Mazda RX-2, RX-3, RX-3SP, RX-7 12A gain 2 bbl fuel injected throttle body option; RX-7 13B gains fuel injected throttle body and stock fuel injection. · EP Mazda RX-2, RX-3, RX-3SP lose 50–52 lbs; RX-4 loses 50–52 lbs across all specs. · EP Triumph TR8 78-81 now allowed dry sump installation. · EP, FP, HP port matching limited to 1 inch depth from mating surface. · EP Prep adds Nissan 280ZX (79-83) at 2425–2546 lbs with 2760cc SOHC six, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit. · Sebeco NP01-EVO and Elan NP01 added to P2 with Mazda 2.0L MZR, no restrictor required, 1600 lb minimum weight. · P2 Radical SR3/SR4, Cup, Club Sport, Pro-Sport, PR6: assisted shifting clarified from A-assisted to Aassisted; Cup engine restrictor changed from Unrestricted to Not required. · P2 chassis now allows composite materials partially installed; anti-intrusion panels attachment simplified; Stohr and converted models clarified. · Spec MX5 in STL allows ACT clutch 0000-02-5004-G6, wheels 17x8, Toyo RR and RA1 235-40-17 tyres, or alternatives on 17x7 per rules.showhide
EP Hub Note Clean Up In EP TR8 Spec Line #34649removedremovedEP Triumph TR8 78-81 removes allowance for alternate front hubs of same external dimensions and weight.
EP Triumph GT6 Adjustments #34662engineengineEP Triumph GT6 carburetor type changes from SU or Stromberg to Auto-type, quantity two 1.5 inch.
EP Triumph GT6 Adjustments: Brakes #34663suspension & brakesaddedsuspension & brakesEP Triumph GT6 Brakes Alt. now permits TR-6 standard or alternate calipers and discs.
AS Crate Motor Part Numbers #32944wordingwordingAS crate motor part number specification clarified; both CT400 P/N-19370604 and 19370604 engine assemblies permitted for GM vehicles.
AS Request wheel size change #33007tyres & wheelsfastertyres & wheelsAS Ford Mustang GT 5.0L (15-17) Restricted maximum wheel diameter increases to 19.0 inches.
AS Alternative Upper Front Control Arms for Dodge Challenger #33352wordingwordingAS Dodge Challenger 5.7L/6.1L/6.4L V8 allows alternate front upper control arms; SPC-66045 spec part removed.
AS Front Brake Caliper Adapters for Dodge Challenger #33353otherotherAS Dodge Challenger 5.7L/6.1L/6.4L V8 now allows alternate front brake calipers with adaptor brackets for component compatibility.
EP Correct Intake Valve Size on 1500cc Midget/Spitfire #34419wordingwordingFP and HP Sprite and Spitfire 1500 intake valve size corrected to 36.6 mm, removing prior decimal specifications.
EP 914-6 Valve Size Correction #34185enginefasterengineEP Porsche 914-6 2.0L intake valve increased to 2.0 mm, exhaust valve corrected to 38.0 mm.
STL Clarify STL table B - IT spec notes on Tires #34187wordingwordingSTL ITA and ITS RX7, and ITS/ITA/ITB/ITC 1985+ models clarified to require tires per 9.1.4.2.
P2 Clarify minimum side body height requirement #34143wordingwordingP2 minimum side body height must equal front axle centerline height, viewed from side.
P2 Clarify closed cockpit single seat car allowance #34144wordingwordingP2 closed cockpit single seat cars now prohibited unless Table 1 spec line permits.
EP Investigate Parity of Z3 #33343inductionslowerinductionEP BMW Z3 2.5L flat plate intake restrictor reduced from 58mm to 56mm, both throttle bodies.
P2 Remove redundant effective date language and update engine table #34012wordingwordingP2 engine table spec line B.1 redundant effective date language removed and table updated.
P2 E&O - Correct dimensional equivalents #34038enginefasterengineP2 motorcycle restrictor reduced 35mm to 34mm for 2011+ Kawasaki; minimum weights increased to 1100 lbs for 2009+ engines; cockpit length corrected to 23.622 inches.
EP Revise 79-85 RX7 Brake Spec Line Allowance #33293otherotherEP 79-85 RX-7 brake hub and rotor spec removed; 13B rotor housing and housing options now permitted.
EP Request alternate carburetors for EP 280z #33405wordingwordingEP Nissan 280Z carburetor option clarified: Hitachi-SU 1bbl 46mm throttle bores or fuel injection permitted.
EP Fuel Injection 12a Mazda RX3 #33434cars addedaddedEP Mazda RX-2, RX-3, RX-3SP, RX-7 12A gain 2 bbl fuel injected throttle body option; RX-7 13B gains fuel injected throttle body and stock fuel injection.
EP Mazda RX3 - Weight Reduction #33436weight -50 lbsfasterweightEP Mazda RX-2, RX-3, RX-3SP lose 50–52 lbs; RX-4 loses 50–52 lbs across all specs.
EP Request TR8 Dry Sump Allowance #33460otheraddedEP Triumph TR8 78-81 now allowed dry sump installation.
EP Review Limited Prep Port Matching Rules #33600wordingwordingEP, FP, HP port matching limited to 1 inch depth from mating surface.
EP 280ZX Classification Request #33611cars addedaddedEP Prep adds Nissan 280ZX (79-83) at 2425–2546 lbs with 2760cc SOHC six, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit.
P2 Request to Classify Sebeco NP01 #33378cars addedaddedSebeco NP01-EVO and Elan NP01 added to P2 with Mazda 2.0L MZR, no restrictor required, 1600 lb minimum weight.
P2 Radical spec line clarifications #33485wordingwordingP2 Radical SR3/SR4, Cup, Club Sport, Pro-Sport, PR6: assisted shifting clarified from A-assisted to Aassisted; Cup engine restrictor changed from Unrestricted to Not required.
P2 E&O original class intent #33519wordingwordingP2 chassis now allows composite materials partially installed; anti-intrusion panels attachment simplified; Stohr and converted models clarified.
STL Spec MX5 in STL #33473cars addedaddedSpec MX5 in STL allows ACT clutch 0000-02-5004-G6, wheels 17x8, Toyo RR and RA1 235-40-17 tyres, or alternatives on 17x7 per rules.
1:47.566Tim Day Jr · fastest of 12 · top 5 within 3.0s-1.545s (-1.42%)
2:15.834Greg Gyann · fastest of 12 · top 5 within 10.1s+25.576s (+23.20%)
151.1Robert Iversen+1.8 mph (+1.2%)
2:02.162Kurt Rezzetano · fastest of 13 · top 5 within 2.3s-0.776s (-0.63%)
2:04.578Gregory Eaton · fastest of 11 · top 5 within 2.9s+0.678s (+0.55%)
150.9James Jost-3.0 mph (-2.0%)
-11.256squal +14.596s
91.7%qual 113.6%
2:05.474Danny Steyn · fastest of 24 · top 5 within 2.3s-1.729s (-1.36%)
2:07.832Danny Steyn · fastest of 22 · top 5 within 1.9s+0.559s (+0.44%)
131.7Trever Degioanni-3.2 mph (-2.3%)
-8.002squal +17.908s
94.1%qual 116.6%
2:02.326Jesse Prather · fastest of 17 · top 5 within 3.2s+1.339s (+1.11%)
2:30.855Jesse Prather · fastest of 15 · top 5 within 2.5s+29.224s (+24.03%)
141.5Jesse Prather-6.0 mph (-4.1%)
+15.021squal +14.760s
111.1%qual 113.7%
45 rule changes (P2: 10, AS: 9, STL: 5, EP: 21)7 weight · 6 cars added · 6 engine · 3 induction · 3 tyres & wheels · 1 aero · 1 suspension & brakes · 15 wording · 3 other · AS adds Hoosier W2 wet tyre option alongside R7, R6, WET/H20. · AS Dodge Challenger 08-20 gains two transmission ratio options: 2.97–0.50 or 2.26–0.63. · Volkswagen New Beetle 2.5L 5-cyl DOHC classified in EP at 2400–2520 lbs with fuel injection. · EP Mazda RX-7 12A/13B and 13B now permit 2 bbl fuel injected throttle body with 42mm chokes on dual-y manifold. · EP VW Corrado 92-95 stroke corrected to 90.3 mm and displacement to 2792 cc. · AS Cadillac CTS-V 6.0L V8 Restricted Prep removes 295 tire size 50 lb penalty. · EP Subaru BRZ title updated to include model years 13–20; Toyota 86/Scion FR-S title likewise updated to 13–20. · 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 2996 cc engine, stock throttle body, 11.0:1 compression and 0.400" valve lift limits. · EP, FP, HP open cars now allow carbon fiber hardtops if they retain OEM exterior profiles. · P2 chassis construction clarified: full composite allowed; partial composite must roll without composite parts installed. · P2 classification wording cleaned up in GCR section 9.1.8.C and GCR contents. · EP Mazda RX-8 13B carburetor option replaced with fuel-injected throttle body or stock fuel injection. · EP, FP, HP Production clarify idle control valve options: stock original allowed, removable with blocked ports, or mechanical replaced with electronic stock type. · P2 Oldsmobile cam rules correct spelling from 'after market' to 'aftermarket' in two sections. · EP BMW Z3 2.5L intake restrictor reduced from 59mm to 58mm flat plate. · Ford Mustang 94-98 weight reduced to 2550/2614/2678 lbs; 99-03 3.8L classified EP at 2700/2768/2835 lbs. · EP, FP, HP Improved Touring cars may use any DOT-approved tyre as defined by 9.3.45. · P2 adds Beasley B2 at 1350 lbs with Mazda 12A, 40.5mm venturi, and up to 16.5in wing chord. · P2 wings: terminology change from 'cord' to 'chord', and 'only' removed from Bobsy and Jondal notes. · P2 Converted F5 cars renamed F500, must retain F500 suspension, minimum width 55 inches. · STU single throttle body weight reduction removed; minimum weights revised down to 2990 lbs at 3000cc from 3300 lbs. · STL and STU Improved Touring vehicles must now conform to section 9.1.4 Tires & Wheels. · EP, FP, HP: stock/original idle control devices permitted unmodified or completely removed with openings blocked. · EP Porsche 968 (92-95) now allowed to run dry sump. · EP 1979-1985 Mazda RX-7 12A and 13B minimum weights cut 50–53 lbs across all spec lines. · P2 motorcycle engines gain 5cc to 1505cc max, two-stroke gains 5cc to 1205cc max, automotive engines add 50 lbs minimum weight to 1350 lbs. · SMG Long Tube Headers: Borla PN 17237 discontinued, approved alternatives American Racing MT3-05134300LSNC or Kooks PN 11312000. · AS Mercury Capri 79-86 removed as separate spec line, merged into Ford Mustang 79-93 spec line. · AS Spec Mustang SMG Restricted Prep removes 3.73 gear ratio and 355/300 brake disc sizes. · AS Camaro, Firebird, Mustang full prep engines: alternate GM and Ford Performance cylinder heads permitted regionally with Allstar restrictor ALL26180. · EP Porsche 968 intake valve size changes to 39.0 mm, 1.54 mm seat width. · EP, FP, HP front-wheel-drive cars may alter body and subframes to install alternate axle shaft, matching RWD freedom. · EP BMW Z3 2.5L adds alternate throttle body option with Turner adapter and permits head casting 1738400. · P2 Control Area definition clarified: rectangular zone from rear edge of front tires to front edge of rear tires, full car width. · STL/STU intake manifold and cylinder head porting clarified as free; intake and exhaust porting wording removed. · STL Mazda Renesis flat plate restrictor increases from 55mm to 60mm. · STL 79-85 RX7 12A allows emissions removal and jet correction on stock Nikki carb. · EP Porsche 944S2 89-91 requires 56mm flat plate intake restrictor; compression ratio 12.0:1 max, valve lift 0.500" max, dry sump allowed. · Toyota Corolla GTS RWD (84-87) and FX16 FWD (87-88) added to HP; old Corolla (84-87) removed. · P2 specification line B.1 engine table entry amended; details of change not provided in excerpt. · P2 Control Area definition clarified: rear tire edge and front tire edge bounds, car's lower surface width, floor extensions and aerodynamic attachments included, vertical structures prohibited. · AS Chevrolet/Pontiac Camaro & Firebird 93-02 gains BMR AA004 or UMI 2310 adjustable front upper control arms. · AS Pontiac GTO 04-06 Restricted Prep minimum weight rises: LS1 to 3300 lbs, LS2 to 3350 lbs on 295 tires. · Toyota MR-2 1.6L 85-89 HP track width corrected to 15×47 / 15×47 inches; stock track baseline now 103% plus 2.5 inches.showhide
AS Request to add Hoosier W2 #33031tyres & wheelsaddedtyres & wheelsAS adds Hoosier W2 wet tyre option alongside R7, R6, WET/H20.
AS correction of Dodge Challenger specification line #33151cars addedaddedAS Dodge Challenger 08-20 gains two transmission ratio options: 2.97–0.50 or 2.26–0.63.
EP Request to classify VW New Beetle 2.5L in EP #32725cars addedaddedVolkswagen New Beetle 2.5L 5-cyl DOHC classified in EP at 2400–2520 lbs with fuel injection.
EP Request Rotary Injection on Dual Y manifold #32775inductionaddedinductionEP Mazda RX-7 12A/13B and 13B now permit 2 bbl fuel injected throttle body with 42mm chokes on dual-y manifold.
EP Request for Corrado Stroke & Displacement Correction #32985wordingwordingEP VW Corrado 92-95 stroke corrected to 90.3 mm and displacement to 2792 cc.
EP Subaru BRZ Model Years #32500wordingwordingEP Subaru BRZ title updated to include model years 13–20; Toyota 86/Scion FR-S title likewise updated to 13–20.
EP EP MX-5 Global Cup Car #32218weightweightEP 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 addedaddedBMW 128i (08-13) classified in EP at 2700 lbs minimum with 2996 cc engine, stock throttle body, 11.0:1 compression and 0.400" valve lift limits.
EP Inconsistency in Body Work Descriptions #32396aeroaddedaeroEP, FP, HP open cars now allow carbon fiber hardtops if they retain OEM exterior profiles.
P2 E&O Clarification of Chassis Construction Requirements #32469wordingwordingP2 chassis construction clarified: full composite allowed; partial composite must roll without composite parts installed.
P2 Clean up P2 wording #32525wordingwordingP2 classification wording cleaned up in GCR section 9.1.8.C and GCR contents.
EP Mazda RX8 with 13b Rotary #32170engineengineEP Mazda RX-8 13B carburetor option replaced with fuel-injected throttle body or stock fuel injection.
EP Request Idle control valve clarification #32178wordingwordingEP, FP, HP Production clarify idle control valve options: stock original allowed, removable with blocked ports, or mechanical replaced with electronic stock type.
P2 After Market to Aftermarket #32373wordingwordingP2 Oldsmobile cam rules correct spelling from 'after market' to 'aftermarket' in two sections.
EP EP Adjustments #31858inductionslowerinductionEP BMW Z3 2.5L intake restrictor reduced from 59mm to 58mm flat plate.
EP 1999 3.8L Ford Mustang to EP? #31635weightfasterweightFord Mustang 94-98 weight reduced to 2550/2614/2678 lbs; 99-03 3.8L classified EP at 2700/2768/2835 lbs.
EP Improved Touring Tires #32064tyres & wheelsaddedtyres & wheelsEP, FP, HP Improved Touring cars may use any DOT-approved tyre as defined by 9.3.45.
P2 Add spec line for Beasley B2 #32147cars addedaddedP2 adds Beasley B2 at 1350 lbs with Mazda 12A, 40.5mm venturi, and up to 16.5in wing chord.
P2 E&O Table 1 spec line wing terminology #32148wordingwordingP2 wings: terminology change from 'cord' to 'chord', and 'only' removed from Bobsy and Jondal notes.
P2 E&O class name #32196wordingwordingP2 Converted F5 cars renamed F500, must retain F500 suspension, minimum width 55 inches.
STL Single TB Weight Modifiers #31449weightfasterweightSTU single throttle body weight reduction removed; minimum weights revised down to 2990 lbs at 3000cc from 3300 lbs.
STL Improved Touring Tires #32063tyres & wheelstyres & wheelsSTL and STU Improved Touring vehicles must now conform to section 9.1.4 Tires & Wheels.
EP Throttle Body and Idle Air #31800wordingwordingEP, FP, HP: stock/original idle control devices permitted unmodified or completely removed with openings blocked.
EP Porsche 968 Engine Questions #31831engineaddedengineEP Porsche 968 (92-95) now allowed to run dry sump.
EP Request weight reduction for 1979-1985 Mazda RX-7 #31833weightfasterweightEP 1979-1985 Mazda RX-7 12A and 13B minimum weights cut 50–53 lbs across all spec lines.
P2 E&O Engine section #31969weightslowerweightP2 motorcycle engines gain 5cc to 1505cc max, two-stroke gains 5cc to 1205cc max, automotive engines add 50 lbs minimum weight to 1350 lbs.
AS Proposed Revisions to SCCA GCR 2021 Appendix M, Part 3 #30295wordingwordingSMG Long Tube Headers: Borla PN 17237 discontinued, approved alternatives American Racing MT3-05134300LSNC or Kooks PN 11312000.
AS specification line consolidation and correction #31846cars addedremovedcars addedAS Mercury Capri 79-86 removed as separate spec line, merged into Ford Mustang 79-93 spec line.
AS correction of SMG specification line #31847wordingremovedAS Spec Mustang SMG Restricted Prep removes 3.73 gear ratio and 355/300 brake disc sizes.
AS Alternate cylinder heads for full prep engine builds - Evaluation #31851engineaddedengineAS Camaro, Firebird, Mustang full prep engines: alternate GM and Ford Performance cylinder heads permitted regionally with Allstar restrictor ALL26180.
EP Porsche 968 Engine Questions #31478engineengineEP Porsche 968 intake valve size changes to 39.0 mm, 1.54 mm seat width.
EP PCS E. 2. n. 4. Add Axle Shaft to Allow FWD the Same Freedom #31592otheraddedEP, FP, HP front-wheel-drive cars may alter body and subframes to install alternate axle shaft, matching RWD freedom.
EP BMW Z3 2.5L Spec Line #31724engineaddedengineEP BMW Z3 2.5L adds alternate throttle body option with Turner adapter and permits head casting 1738400.
P2 E&O letter #31539 – Control Area definition #31783wordingwordingP2 Control Area definition clarified: rectangular zone from rear edge of front tires to front edge of rear tires, full car width.
STL Throttling Device Clarification #31323wordingwordingSTL/STU intake manifold and cylinder head porting clarified as free; intake and exhaust porting wording removed.
STL Mazda Renesis Restriction #31467enginefasterengineSTL Mazda Renesis flat plate restrictor increases from 55mm to 60mm.
STL Clarification of 79-85 RX7 Spec line #31621wordingwordingSTL 79-85 RX7 12A allows emissions removal and jet correction on stock Nikki carb.
EP Classing Clarification for 1986 Toyota Corolla FX16 #31527cars addedaddedToyota Corolla GTS RWD (84-87) and FX16 FWD (87-88) added to HP; old Corolla (84-87) removed.
P2 BoP adjustment effective 1-1-22 #31538otherunclearP2 specification line B.1 engine table entry amended; details of change not provided in excerpt.
P2 E&O clarification of "Control Area" definition #31539wordingwordingP2 Control Area definition clarified: rear tire edge and front tire edge bounds, car's lower surface width, floor extensions and aerodynamic attachments included, vertical structures prohibited.
AS Request for adjustable Front Upper Control Arms on 4th Gen F-Body #30457otheraddedAS Chevrolet/Pontiac Camaro & Firebird 93-02 gains BMR AA004 or UMI 2310 adjustable front upper control arms.
AS Request Pontiac GTO tire size change #30881weightslowerweightAS Pontiac GTO 04-06 Restricted Prep minimum weight rises: LS1 to 3300 lbs, LS2 to 3350 lbs on 295 tires.
EP E&O; MR2 Track #31120suspension & brakessuspension & brakesToyota MR-2 1.6L 85-89 HP track width corrected to 15×47 / 15×47 inches; stock track baseline now 103% plus 2.5 inches.
1:33.235Tim Day Jr · fastest of 16 · top 5 within 3.3s+1.409s (+1.53%)
1:35.322Tim Day Jr · fastest of 10 · top 5 within 4.8s+2.841s (+3.07%)
150.3Robert Iversen
1:50.427Drew Cattell · fastest of 31 · top 5 within 1.9s+5.207s (+4.95%)
1:50.606Gregory Eaton · fastest of 28 · top 5 within 1.7s-0.901s (-0.81%)
153.8James Jost
+15.284squal +17.192s
116.0%qual 118.4%
1:51.665Danny Steyn · fastest of 42 · top 5 within 1.7s-0.982s (-0.87%)
2:02.711Joe Moser · fastest of 37 · top 5 within 3.2s+10.122s (+8.99%)
131.8Max Gee
+27.389squal +18.430s
128.7%qual 119.8%
1:48.181Jesse Prather · fastest of 31 · top 5 within 3.2s-1.416s (-1.29%)
1:49.928Jesse Prather · fastest of 27 · top 5 within 0.9s-0.468s (-0.42%)
143.4Jon Brakke
+14.606squal +14.946s
115.3%qual 116.0%
51 rule changes (P2: 8, AS: 14, STL: 15, EP: 14)13 cars added · 9 weight · 7 engine · 2 aero · 2 induction · 1 suspension & brakes · 12 wording · 5 other · P2 CN Honda K20A-FD2 engine rebuild clarified: balancing, porting, polishing prohibited; valve jobs and honing must follow factory procedures. · STL Mazda Spec MX-5 removes redundant specification line referencing 2014 regulations. · EP Honda S2000 now allows F22c engine in 1997cc and 2157cc displacements with revised weight brackets and specifications. · EP Nissan 240-SX S13/S14 weight drops to 2400 lbs base, 2460 turbo, 2520 supercharged; comp ratio raised to 12.0:1, valve lift to 0.500 inch. · P2 Converted F5 cars must retain F5 suspension and meet P2 non-spec requirements except minimum width is 55 inches. · P2 minimum body width clarified: cannot extend inward beyond vertical plane through tire centerlines. · EP Lotus/Caterham 7 America fuel injection permitted; IT preparation engine limitation removed. · Daimler SP 250 classified in EP with 2165 lbs minimum weight, 2548 cc eight-cylinder OHV engine, SU or Stromberg carburetors. · AS Cadillac CTS-V 6.0L LS6 removes 295-tire 50 lb penalty. · AS consolidates seven SN95 Mustang '94-'04 spec lines into three unified lines by model year and engine. · AS Camaro/Firebird LT1 and LS1 transmission changed to TUET1 6362; Mustang GT 4.6L/5spd to TUKT16901, loses 300 lbs. · AS Camaro & Firebird and Mustang GT gear ratio specifications restored with alternate sets permitted. · AS Camaro, Firebird, Mustang, and Capri all gain 50 lbs minimum weight across seven model year variants. · EP, FP, HP clarify percentage weight penalties sum before applying to base weight, round to nearest pound. · STL Volkswagen 2.0L TFSI 1984 cc engine permitted without turbocharger, meeting all other STL specs. · 84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lb weight, 1998cc SOHC engine, two 32mm carburetors. · FP Fiat X1/9 and Bertone 1300 brake rotors now 257 x 12 mm, 10.1 inch diameter, 0.407 inch thickness. · EP Mazda MX-5 model year range corrected from 06-14 to 06-15. · P2 tonneau covers now allowed to meet minimum dimensions; cockpit equipment attachment wording clarified. · P2 removes effective date 01/01/2021 from six car spec lines in Table 1. · P2 engine specs B.1, B.2, B.3 limited to maximum 4 valves per cylinder. · STL Pontiac Solstice/Saturn Sky allowed 4 inch ride height. · STL Mazda B5 DOHC added to class; must meet all STL regulations. · STL Honda B16A (JDM) restrictor reduced from 54mm to 53mm. · Mazda 3 S 04-08 classified in EP at 2350 lbs minimum, 2.26L DOHC four-cylinder, fuel injected with 55mm throttle body, comp ratio 12.0:1 max, valve lift 0.500" max. · ST oil coolers and filters now explicitly listed as addable or substitutable parts in vents and breathers section. · AS Mustang 4.6L 5spd gains cold air intake freedom; 5.0L 6spd now requires 56mm flat plate restrictor. · AS CTS-V 5.7L LS6 and 6.0L LS2 may use Driveshaft Shop P/N GMCTSV2-C carbon fiber driveshaft. · AS Chevrolet Camaro SS V8 6.2L Restricted Prep model years extended from 10–13 to 10–15. · P2 adds new spec line for 2-cycle 3-cylinder engine up to 820cc with 10 front, 14–15 rear wheel width. · STL GM Ecotec LNF now permits any Ecotec engine family with 55mm flat plate restrictor. · ST 90-05 Mazda Miata allowed alternate front wheel hub Mazda Motorsports Development Part #0000-04-5HUB-S1. · ST cars may now relocate ABS actuation hardware and wiring anywhere in the engine compartment. · STL rear wing trailing edge may be mounted no further rearward than the center of the rearmost part approved bodywork. · STL alternate transmissions now allow OEM gear sets and input shaft modifications for fitment. · AS Ford Mustang GT 5.0L 15-17 Restricted added to Spec Line with 3600 lbs minimum weight, 55mm restrictor, 18×10 wheels, 295 tires. · AS underhood bracing on stock hoods, trunks, and rear decks may be modified or removed. · AS Cadillac CTS-V 04-07 with 295 tire drops to 3450 lbs; Camaro SS V8 10-13 and Challenger 08-20 specs removed. · AS Camaro & Firebird (93-02) and Mustang GT (05-14) specifications restored with weight minimums 3250–3500 and 3350–3600 lbs respectively. · EP Austin-Healey 3000 gains option to use TR-6 front calipers and discs as alternate. · STL RWD strut-front cars lose 2.5% weight penalty, others lose 3% penalty for FWD parity. · STL Honda F20C drops 2% weight penalty, minimum weight reduced. · STL Honda B16/B17/B18C1 restrictor reduced to 53mm, B18C variants and Mazda MZR to 52mm. · AS Dodge Challenger gains 6.1L and 6.4L V8 options; 5.7L weight rises to 3500 lbs on 295 tyres, 3600 on 315 tyres; compression to 10.9:1 max. · AS Camaro & Firebird (93-02) and Ford Mustang Coupe GT (05-14) spec lines consolidated; Camaro/Firebird now allows both LT1 and LS1 engines; Mustang now allows both 4.6L 3-valve and 5.0L 4-valve engines with restrictor. · FP Mk2 Golf and Jetta 1.8 lose 50 lbs to 1900; HP Jetta GLI engine code removed. · EP, FP, HP Level 1 and Level 2 induction systems: carburettor jets, needles, metering rods allowed; throttle body porting permitted; wording clarified. · EP Nissan Datsun SRL 311U Roadster minimum weight reduced 75 lbs to 1925. · EP Triumph TR8 78-81 minimum weight drops to 2500 lbs. · P2 motorcycle-engine cars: 2009+ stock 37mm restrictor, 2008- stock 35mm, modified 1075 lbs. Honda K20A 50mm restrictor. Various spec cars: restrictors increased or decreased 0.5–3mm. · ST aero devices and reference areas must include end plates, exclude fasteners under 1/2" protrusion.showhide
P2 P2 CN Engine Rebuild Clarification #31000wordingwordingP2 CN Honda K20A-FD2 engine rebuild clarified: balancing, porting, polishing prohibited; valve jobs and honing must follow factory procedures.
STL Request to clean up Spec MX-5 Redundancy #31069wordingwordingSTL Mazda Spec MX-5 removes redundant specification line referencing 2014 regulations.
EP Request to Allow F22c Engine for 2000-2003 Honda S2000 #30548cars addedaddedEP Honda S2000 now allows F22c engine in 1997cc and 2157cc displacements with revised weight brackets and specifications.
EP Request a review of the S14 240SX in EP. #30873weight -200 lbsfasterweightEP Nissan 240-SX S13/S14 weight drops to 2400 lbs base, 2460 turbo, 2520 supercharged; comp ratio raised to 12.0:1, valve lift to 0.500 inch.
P2 F5 P2 Conversion #30856wordingwordingP2 Converted F5 cars must retain F5 suspension and meet P2 non-spec requirements except minimum width is 55 inches.
P2 Clarify minimum body width requirement #30859wordingwordingP2 minimum body width clarified: cannot extend inward beyond vertical plane through tire centerlines.
EP Lotus/Caterham 7 America Request #30392wordingwordingEP Lotus/Caterham 7 America fuel injection permitted; IT preparation engine limitation removed.
EP Reclassify Daimler SP 250 #30721cars addedaddedDaimler SP 250 classified in EP with 2165 lbs minimum weight, 2548 cc eight-cylinder OHV engine, SU or Stromberg carburetors.
AS Request CTS-V Spec Line Error Correction #30242weightfasterweightAS Cadillac CTS-V 6.0L LS6 removes 295-tire 50 lb penalty.
AS Request to consolidate SN95 Mustang '94-'04 Mustang spec lines #30428wordingwordingAS consolidates seven SN95 Mustang '94-'04 spec lines into three unified lines by model year and engine.
AS American Sedan Transmission Rule Change Request #30595enginefasterengineAS Camaro/Firebird LT1 and LS1 transmission changed to TUET1 6362; Mustang GT 4.6L/5spd to TUKT16901, loses 300 lbs.
AS Correction to specifications inadvertently deleted #30691wordingwordingAS Camaro & Firebird and Mustang GT gear ratio specifications restored with alternate sets permitted.
AS weight adjustments #30700weight +50 lbsslowerweightAS Camaro, Firebird, Mustang, and Capri all gain 50 lbs minimum weight across seven model year variants.
EP Clarify Application of Percentage Based Weight Penalties #30669wordingwordingEP, FP, HP clarify percentage weight penalties sum before applying to base weight, round to nearest pound.
STL VW Engine Request #30625engineaddedengineSTL Volkswagen 2.0L TFSI 1984 cc engine permitted without turbocharger, meeting all other STL specs.
EP Change Classification of 84-87 Mazda 626 from FP to HP #30350cars addedadded84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lb weight, 1998cc SOHC engine, two 32mm carburetors.
EP Fiat X1/9 brake rotors #30423otherotherFP Fiat X1/9 and Bertone 1300 brake rotors now 257 x 12 mm, 10.1 inch diameter, 0.407 inch thickness.
EP NC MX-5 year range correction E&O #30503cars addedaddedEP Mazda MX-5 model year range corrected from 06-14 to 06-15.
P2 E&O tonneau cover provision in cockpit opening section #30459wordingwordingP2 tonneau covers now allowed to meet minimum dimensions; cockpit equipment attachment wording clarified.
P2 Remove effective dates in Table 1 #30468wordingwordingP2 removes effective date 01/01/2021 from six car spec lines in Table 1.
P2 E&O Maximum Valves Per Cylinder #30560engineengineP2 engine specs B.1, B.2, B.3 limited to maximum 4 valves per cylinder.
STL Request Mazda B5 DOHC #30420cars addedaddedSTL Mazda B5 DOHC added to class; must meet all STL regulations.
STL Honda B16A (JDM) Restrictor change #30531engineslowerengineSTL Honda B16A (JDM) restrictor reduced from 54mm to 53mm.
EP Please Classify Mazda3 in FP #30165cars addedaddedMazda 3 S 04-08 classified in EP at 2350 lbs minimum, 2.26L DOHC four-cylinder, fuel injected with 55mm throttle body, comp ratio 12.0:1 max, valve lift 0.500" max.
STL ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wordingwordingST oil coolers and filters now explicitly listed as addable or substitutable parts in vents and breathers section.
AS AS Mustang LP 4.6 3V Classification Transmission Request #29886enginefasterengineAS Mustang 4.6L 5spd gains cold air intake freedom; 5.0L 6spd now requires 56mm flat plate restrictor.
AS Request CF driveshaft on CTS-V for durability improvement #30117otheraddedAS CTS-V 5.7L LS6 and 6.0L LS2 may use Driveshaft Shop P/N GMCTSV2-C carbon fiber driveshaft.
AS Adjustment to model years of 5th generation RP Camaro #30348cars addedaddedAS Chevrolet Camaro SS V8 6.2L Restricted Prep model years extended from 10–13 to 10–15.
P2 Add a new spec line for a 2-cycle, 3-cylinder engine up to 820cc #30272cars addedaddedP2 adds new spec line for 2-cycle 3-cylinder engine up to 820cc with 10 front, 14–15 rear wheel width.
STL GM Ecotec engines in STL #30247engineaddedengineSTL GM Ecotec LNF now permits any Ecotec engine family with 55mm flat plate restrictor.
STL Super Touring Alternate Miata Hubs #30345cars addedaddedST 90-05 Mazda Miata allowed alternate front wheel hub Mazda Motorsports Development Part #0000-04-5HUB-S1.
STL Brake Component Relocation #29990suspension & brakessuspension & brakesST cars may now relocate ABS actuation hardware and wiring anywhere in the engine compartment.
STL Super Touring Wing Clarification #30111aeroaeroSTL rear wing trailing edge may be mounted no further rearward than the center of the rearmost part approved bodywork.
STL Transmission Options #30118otheraddedSTL alternate transmissions now allow OEM gear sets and input shaft modifications for fitment.
AS Request for 2015 -2017 Ford Mustang Spec Line #29514cars addedaddedAS Ford Mustang GT 5.0L 15-17 Restricted added to Spec Line with 3600 lbs minimum weight, 55mm restrictor, 18×10 wheels, 295 tires.
AS Request Trunk lid / Rear Hatch clarification #29591wordingwordingAS underhood bracing on stock hoods, trunks, and rear decks may be modified or removed.
AS Common Weight for CTS-V Tire #29759weightfasterweightAS Cadillac CTS-V 04-07 with 295 tire drops to 3450 lbs; Camaro SS V8 10-13 and Challenger 08-20 specs removed.
AS Correction to specifications inadvertently deleted #30041cars addedaddedAS Camaro & Firebird (93-02) and Mustang GT (05-14) specifications restored with weight minimums 3250–3500 and 3350–3600 lbs respectively.
EP Alternate Front Brake Rotors and Calipers for EP AH 3000 #29893otherotherEP Austin-Healey 3000 gains option to use TR-6 front calipers and discs as alternate.
STL Request for FWD and RWD Parity #29728weightfasterweightSTL RWD strut-front cars lose 2.5% weight penalty, others lose 3% penalty for FWD parity.
STL Request for FWD and RWD Parity #30023inductionslowerinductionSTL Honda B16/B17/B18C1 restrictor reduced to 53mm, B18C variants and Mazda MZR to 52mm.
AS Request Additional Engine Options for Dodge Challenger Spec Line #29543cars addedaddedAS Dodge Challenger gains 6.1L and 6.4L V8 options; 5.7L weight rises to 3500 lbs on 295 tyres, 3600 on 315 tyres; compression to 10.9:1 max.
AS Rule simplification spec line communization #29824cars addedcars addedAS Camaro & Firebird (93-02) and Ford Mustang Coupe GT (05-14) spec lines consolidated; Camaro/Firebird now allows both LT1 and LS1 engines; Mustang now allows both 4.6L 3-valve and 5.0L 4-valve engines with restrictor.
EP Mk2 VW Consistency and Cleanup of FP and HP Spec Lines #29195weight -50 lbsfasterweightFP Mk2 Golf and Jetta 1.8 lose 50 lbs to 1900; HP Jetta GLI engine code removed.
EP Correct Wording for Level 1 and Level 2 Induction Systems #29406inductionfasterinductionEP, FP, HP Level 1 and Level 2 induction systems: carburettor jets, needles, metering rods allowed; throttle body porting permitted; wording clarified.
EP Weight Reduction for Datsun Roadster #29409weight -75 lbsfasterweightEP Nissan Datsun SRL 311U Roadster minimum weight reduced 75 lbs to 1925.
EP EP TR8 Adjustment #29512weight -100 lbsfasterweightEP Triumph TR8 78-81 minimum weight drops to 2500 lbs.
STL Request clarification on wing measurement #29640aeroaeroST aero devices and reference areas must include end plates, exclude fasteners under 1/2" protrusion.
2:08.514Robert Iversen · fastest of 12 · top 5 within 3.0s
2:09.793Robert Iversen · fastest of 12 · top 5 within 3.9s
153.1Robert Iversen
2:27.045Gregory Eaton · fastest of 18 · top 5 within 0.6s
2:27.668Gregory Eaton · fastest of 15 · top 5 within 1.5s
149.2Gregory Eaton
+17.875squal +18.531s
113.8%qual 114.4%
2:31.420Danny Steyn · fastest of 33 · top 5 within 3.1s
2:32.115Joe Moser · fastest of 30 · top 5 within 1.5s
132.9Darin Treakle
+22.322squal +22.906s
117.2%qual 117.8%
2:27.322Jesse Prather · fastest of 20 · top 5 within 2.5s
2:29.047Jesse Prather · fastest of 20 · top 5 within 2.8s
141.7Jesse Prather
+19.254squal +18.808s
114.8%qual 114.6%
47 rule changes (P2: 6, AS: 16, STL: 11, EP: 14)11 engine · 9 cars added · 3 induction · 3 weight · 2 aero · 1 suspension & brakes · 15 wording · 3 other · HP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches. · P2 rear wing rules clarified: standard wing 6×12 inches, end plates 14-inch square; alternate 1-meter formula wing 110cm wide, 9×18 inches, end plates 14×18 inches. · AS Dodge Challenger 5.7L V8 now requires iron block instead of aluminum, compression to 10.5:1 max, intake valve 12.7 mm, exhaust 12.3 mm, intake timing 188 degrees, exhaust timing 205 degrees. · AS Dodge Challenger 08-14 rear spoiler: 1GL20RXF replaced with 1GL20TZZAB; 82211606 still permitted. · EP BMW Z3 2.5L cylinder head casting 1738400 permitted with iron block castings 1748933 or 1738566. · STL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis percentage additions, subtractions, and fixed pounds. · STL STU rear wing Gurney flap terminology clarified from wicker to Gurney flap in mounting and chord rules. · AS class pursuing specified list of eligible tires; list details unclear from text provided. · AS class tire eligibility list under development; no specifications changed yet. · AS Coyote Mustang restrictor plate under review for 2021; no change effective yet. · AS Restricted Prep 4.6 3V now permits conversion to 2 valve configuration. · AS Ford Mustang Coupe GT 4.6L 3V Restricted Prep now permits Ford Performance camshaft kit P/N M-6550-3V. · 2010-2014 Camaro remains classified in AS; no specification changes. · AS class cylinder head supplier discontinuation; replacement option pending for 2021 season. · AS Mustang, Capri, Camaro, and Firebird maximum brake rotor diameter increased from 12.2 to 13.1 inches. · unclear · Porsche 911 S 67-68 classified in EP at 1800–1890 lbs, 1991cc opposed 6-cylinder SOHC with 36mm carburetors. · GT3 and STU add Borg-Warner EFR6258 turbocharger to approved turbo lists. · EP BMW 2.8L, 328i E36/E46, and 325i E36 now require iron blocks only; 325i E46 aluminum block removed. · Elan NP01 added to P2 Table 1 as Spec Line car with 2000cc displacement and 42mm restrictor. · STL adds Mazda MX-5 Global Cup 16-18 at 2450 lbs minimum and 2019 at 2550 lbs minimum. · STL Mazda MX-5 Club 06-15 allowed header part number 0000-06-5407-NC. · STL Acura/Honda B18 and B18C engines: restrictor sizes swapped, B18C1 removed from allowed variants. · FP Pre: 1990–1994 Mazda Protégé classified at 2150–2258 lbs, 1839cc DOHC, fuel injection, 11.0:1 compression, .450" valve lift limit. · HP Mini Cooper 02-06 and 07-13 convertible model years corrected to 05-08 and 09-15 respectively. · P2 Enterprises Sports Racer now permits 55mm flat plate intake restrictor Part # WM303013 as alternative to SIR. · STL Honda B18 loses 53mm restrictor requirement; B18C1 added with 54mm restrictor, B18C1 removed from other variants. · EP Caterham 7 America engine limited to IT prep with specific sections, comp ratio 10.0:1, valve lift .380 inch. · P2 Enterprise Sports Racer 2.3L engine must use SIR or Flat Plate restrictor meeting peak horsepower, sized in whole or 0.5mm increments. · STU GM Ecotech LNF now permitted without turbo, with LE5 head and intake manifold, meeting STL specs. · STL Mazda MZR restrictor reduced from 54 mm to 53 mm. · STL Mazda MZR restrictor reduces from 55 mm to 53 mm. · EP BMW 325is M-Technic 1994 minimum weight cut to 2550 lbs, modifier weights to 2614 and 2678. · HP Datsun 510 allows 40 DCOE carburetor option alongside existing 40 DCNF and 36mm DCNVH; auto side drafts moved to penalty structure. · EP fuel-injected BMW throttle body maximum inside diameter set to 64 mm. · P2 electronic throttle control wording clarified: ETC permitted if stock ECU throttle pedal activates original throttle shaft mechanism. · STL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL to notes. · AS rear trailing arms may be replaced with tubular arms maintaining stock length and axle location purpose only. · AS Ford and GM full prep cars get increased weight reduction from 150 to 200 lbs. · 05-10 Ford Mustang Coupe GT 4.6L OHC classified AS with 3200 lbs minimum weight, HR cam permitted. · 10-15 Camaro Full Prep classified AS with 3400 lbs base weight, 3700 lbs over 313 CID, specific head castings and Edelbrock heads permitted. · HP Datsun 1200 carburetor option changes from 26mm to 30mm choke(s) in 40 DCN, DCNF, IDF. · Mazda Miata models EP and FP throttle body specified 55mm, brake rotor thickness figures removed. · P2 adds BMW to permitted motorcycle-based engines alongside Kawasaki, Suzuki, Yamaha, Honda. · EP, FP, HP cylinder head rules reorganized for clarity; no performance change.showhide
EP 84-87 Toyota Corolla HP Wheel Diameter Allowance Proposal E&O #29458otherfasterHP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches.
P2 E&O clarification of P2 rear wing requirements #29205aeroaeroP2 rear wing rules clarified: standard wing 6×12 inches, end plates 14-inch square; alternate 1-meter formula wing 110cm wide, 9×18 inches, end plates 14×18 inches.
AS Dodge Challenger AS Spec Line Clarification #28698engineslowerengineAS Dodge Challenger 5.7L V8 now requires iron block instead of aluminum, compression to 10.5:1 max, intake valve 12.7 mm, exhaust 12.3 mm, intake timing 188 degrees, exhaust timing 205 degrees.
AS Dodge Challenger AS Spec Line Clarification #2 #28699aeroaeroAS Dodge Challenger 08-14 rear spoiler: 1GL20RXF replaced with 1GL20TZZAB; 82211606 still permitted.
EP EP BMW Z3 Rule Clarification #28998wordingwordingEP BMW Z3 2.5L cylinder head casting 1738400 permitted with iron block castings 1748933 or 1738566.
STL Minimum Weight Determination #27695wordingwordingSTL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis percentage additions, subtractions, and fixed pounds.
STL ST Gurney flap Wicker clarification #29012wordingwordingSTL STU rear wing Gurney flap terminology clarified from wicker to Gurney flap in mounting and chord rules.
AS Support for R-Type Specification Tires #27450wordingunclearAS class pursuing specified list of eligible tires; list details unclear from text provided.
AS Spec Tire Request #27519wordingunclearAS class tire eligibility list under development; no specifications changed yet.
AS Restrictor Plate Change for RP 2011+ Mustang with Coyote Engine #27675wordingunclearAS Coyote Mustang restrictor plate under review for 2021; no change effective yet.
AS 2005-2009 Restricted Prep 4.6 3V #27908engineaddedengineAS Restricted Prep 4.6 3V now permits conversion to 2 valve configuration.
AS Request for 2005-2009 Restricted Prep 4.6 3V Parts #27909engineaddedengineAS Ford Mustang Coupe GT 4.6L 3V Restricted Prep now permits Ford Performance camshaft kit P/N M-6550-3V.
AS Request for Full Preparation Classification for 2010-2014 Camaro #28030wordingunclear2010-2014 Camaro remains classified in AS; no specification changes.
AS Cylinder Heads #28696wordingunclearAS class cylinder head supplier discontinuation; replacement option pending for 2021 season.
AS Request for Max Rotor Diameter Change #28748otherfasterAS Mustang, Capri, Camaro, and Firebird maximum brake rotor diameter increased from 12.2 to 13.1 inches.
AS Request increase rotor diameter #28797wordingunclearunclear
EP Request to Classify Porsche 911 2.0L #28456cars addedaddedPorsche 911 S 67-68 classified in EP at 1800–1890 lbs, 1991cc opposed 6-cylinder SOHC with 36mm carburetors.
STL Request for Addition to GT3 Approved Turbo List #27576cars addedaddedGT3 and STU add Borg-Warner EFR6258 turbocharger to approved turbo lists.
EP BMW Cylinder Head Casting and Part Numbers #28708engineslowerengineEP BMW 2.8L, 328i E36/E46, and 325i E36 now require iron blocks only; 325i E46 aluminum block removed.
P2 Classify Elan NP01 in P2 Table 1 #28812cars addedaddedElan NP01 added to P2 Table 1 as Spec Line car with 2000cc displacement and 42mm restrictor.
STL Request to add 2016-2019 GMX-5 Spec line #28604cars addedaddedSTL adds Mazda MX-5 Global Cup 16-18 at 2450 lbs minimum and 2019 at 2550 lbs minimum.
STL Request to update PN for MX-5 #28622cars addedaddedSTL Mazda MX-5 Club 06-15 allowed header part number 0000-06-5407-NC.
STL Correction - Clarification Honda/Acura B18B engine Letter # 26209 #28873wordingwordingSTL Acura/Honda B18 and B18C engines: restrictor sizes swapped, B18C1 removed from allowed variants.
AS weight adjustments for 2020 season #28785weight -50 lbs
EP Request to Classify 1990-1994 Mazda Protege #28381cars addedaddedFP Pre: 1990–1994 Mazda Protégé classified at 2150–2258 lbs, 1839cc DOHC, fuel injection, 11.0:1 compression, .450" valve lift limit.
EP Error in Mini Cooper Spec Line #28713wordingwordingHP Mini Cooper 02-06 and 07-13 convertible model years corrected to 05-08 and 09-15 respectively.
P2 SCCA Enterprises ESR / P2 engine restrictor testing #28669otheraddedP2 Enterprises Sports Racer now permits 55mm flat plate intake restrictor Part # WM303013 as alternative to SIR.
STL STL Honda B18 restrictor changes #28794enginefasterengineSTL Honda B18 loses 53mm restrictor requirement; B18C1 added with 54mm restrictor, B18C1 removed from other variants.
EP Caterham 7 Spec Line #28498wordingwordingEP Caterham 7 America engine limited to IT prep with specific sections, comp ratio 10.0:1, valve lift .380 inch.
P2 Add ESR inlet restrictor #27869inductionaddedinductionP2 Enterprise Sports Racer 2.3L engine must use SIR or Flat Plate restrictor meeting peak horsepower, sized in whole or 0.5mm increments.
STL Change GM LNF 2.0 Allowance to LSJ Engine for Viable STL 2.0 #27884engineaddedengineSTU GM Ecotech LNF now permitted without turbo, with LE5 head and intake manifold, meeting STL specs.
STL Acura/Honda B18C engine chart. Reduce the current 54 mm flat plat #28663engineslowerengineSTL Mazda MZR restrictor reduced from 54 mm to 53 mm.
STL Mazda MZR engine chart. Reduce the current 55 mm flat plate to 53 #28664engineslowerengineSTL Mazda MZR restrictor reduces from 55 mm to 53 mm.
EP Request to Review Horsepower Parity #27662induction
EP E36 (92-95) Brakes Errors and Omissions #28058weightfasterweightEP BMW 325is M-Technic 1994 minimum weight cut to 2550 lbs, modifier weights to 2614 and 2678.
EP Request to allow 40 DCOE carb for the Datsun 510 #28195engineaddedengineHP Datsun 510 allows 40 DCOE carburetor option alongside existing 40 DCNF and 36mm DCNVH; auto side drafts moved to penalty structure.
EP Add Throttle Body Size these EP BMW Spec Lines #28422engineslowerengineEP fuel-injected BMW throttle body maximum inside diameter set to 64 mm.
P2 Request for Fly by Wire Rule Wording Change #28247wordingwordingP2 electronic throttle control wording clarified: ETC permitted if stock ECU throttle pedal activates original throttle shaft mechanism.
STL Request to add wheel part numbers #28342cars addedaddedSTL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL to notes.
AS Rear Trailing Arms #28007suspension & brakesaddedsuspension & brakesAS rear trailing arms may be replaced with tubular arms maintaining stock length and axle location purpose only.
AS Weight reduction for cars running iron heads #28010weightfasterweightAS Ford and GM full prep cars get increased weight reduction from 150 to 200 lbs.
AS 05-10 Mustang with HR cam classification #28226cars addedadded05-10 Ford Mustang Coupe GT 4.6L OHC classified AS with 3200 lbs minimum weight, HR cam permitted.
AS 10-15 Camaro Full Prep classification #28227cars addedadded10-15 Camaro Full Prep classified AS with 3400 lbs base weight, 3700 lbs over 313 CID, specific head castings and Edelbrock heads permitted.
EP Request for Help for Datsun 1200 #27934inductionfasterinductionHP Datsun 1200 carburetor option changes from 26mm to 30mm choke(s) in 40 DCN, DCNF, IDF.
EP Request to List Mazda Miata Throttle Body Size #27907wordingwordingMazda Miata models EP and FP throttle body specified 55mm, brake rotor thickness figures removed.
P2 Request for addition of BMW Engine in P2 Engine Table #27821engineaddedengineP2 adds BMW to permitted motorcycle-based engines alongside Kawasaki, Suzuki, Yamaha, Honda.
EP Re-organize Prep2 Cylinder Head Rules for Clarity & Consistency #27661wordingwordingEP, FP, HP cylinder head rules reorganized for clarity; no performance change.
1:49.111Robert Iversen · fastest of 14 · top 5 within 0.8s
1:50.258Greg Gyann · fastest of 13 · top 5 within 0.4s
149.4Robert Iversen
2:02.938Gregory Eaton · fastest of 17 · top 5 within 0.8s
2:03.900James Jost · fastest of 16 · top 5 within 2.1s
153.9James Jost
+13.642squal +13.827s
112.4%qual 112.7%
2:07.203Danny Steyn · fastest of 36 · top 5 within 1.8s
2:07.273Cliff Ira · fastest of 35 · top 5 within 1.4s
134.8Cliff Ira
+17.015squal +18.092s
115.4%qual 116.6%
2:00.987Jesse Prather · fastest of 29 · top 5 within 2.2s
2:01.631Jesse Prather · fastest of 24 · top 5 within 1.4s
147.5Kip Van Steenburg
+11.373squal +11.876s
110.3%qual 110.9%
34 rule changes (P2: 9, AS: 4, STL: 11, EP: 10)8 cars added · 8 engine · 4 weight · 2 aero · 2 induction · 8 wording · 2 other · AS Spec Mustang (SMG) added as Restricted Prep class. · P2 Honda K20A-FD2 non-composite chassis intake restrictor note clarified; restrictor implementation date removed. · STL adds Mazda Spec MX-5 Challenge, 2000cc displacement, 2500 lb minimum weight, with mandatory Roush, Penske, Eibach, and other specified components. · FP and HP Austin-Healey Sprite Mk I / MG Midget may replace rear bodywork aft of cockpit with alternate material stock-appearing components. · EP Mazda MX-5 Global Cup classification updated to include 2019 model year. · Production classes: suspension rule clarified to specify spindles, hubs, bushings, bearings, and ball joints unrestricted. · Production carburetor and fuel injection rules clarified: permitted optional carburetors listed, Weber and auto-type substitutions specified, fuel injection throttle body and butterfly dimensions detailed, intake manifold port extension pr… · EP, FP, HP carburetors: jets, needles, metering rods, needle valves unrestricted; choke parts removable; stock or optional Weber 40 DCN permitted; Weber types, auto types listed. · P2 motorcycle engines: Stock restrictor to 35mm, Modified to 34mm; weights up to 1025 and 1125 lbs respectively. B.5 restrictor to 33mm, weight to 1185 lbs. · AS class ride height minimum clarified: five inches measured at rocker panel, excluding seams and stock effects. · EP Mazda MX-5/Miata model years expand from 1999-2002 to 1999-2005. · P2 cars limited to power application on maximum two wheels. · STU allows alternate intake manifolds on case-by-case basis; stock throttle device and manifold otherwise required. · P2 Enterprise minimum weight increased to 1375 lbs.; peak horsepower of sealed ESR engine reduced per CRB specification. · AS Ford Mustang 79-93 non-Cobra drops 100 lbs to 3150; over 313 CID Cobra drops 100 lbs to 3450. · STL Acura/Honda B18 except C engine restrictor increased from 53mm to 54mm flat plate. · EP Mazda RX-8 firewall may be modified for 13B engine fitment and must be sealed. · STL and STU ride height measurement clarified: lowest rocker panel point without driver, excluding pinch weld. · EP, FP, HP: clarified that tapered holes in ball joints can be reamed for bolt conversion, and wheel bearings and hubs unrestricted on all axles. · EP open cars may now use aftermarket hardtops if OEM-appearance and non-carbon-fiber; specific model allowances removed as redundant. · EP Mazda RX-7 12A and 13B (79-85) lose up to 75 lbs; 13B (86-91) loses up to 79 lbs across three weight classes. · P2 stock and modified engines get smaller restrictors (35.0mm, 34.0mm, 33.0mm) and heavier minimums (1025, 1125, 1185 lbs). · P2 Line A.1 restrictor reduced from 40mm to 38mm. · STL adds VW 1.8L R4 20VT 1781 cc, 1781 minimum weight, naturally aspirated only. · STL Mazda Renesis minimum weight reduced to 2700 lbs. · STL Mazda MX-5 Cup brake pad compound now open. · STL adds Acura/Honda B18C1 GSR with 1797cc displacement, 54mm flat plate restrictor required, porting outside 1" allowance prohibited. · STL Mazda 12 and 13B now permit port matching; porting ban removed. · AS adds Spec Mustang SMG classification with 107.1 wheelbase, 3.73 gears, 355mm front and 300mm rear brakes. · P2 Spec Line cars now allow 1345cc Hayabusa stock engines at 1050 lb minimum with 30mm restrictor. · P2 Group CN Honda K20A-FD2 55mm intake restrictor implementation delayed from 1 January to 3 March 2019. · P2 Honda K20A-FD2 Group CN must use stock intake manifold, 64mm throttle, 55mm restrictor at 1500 lbs minimum. · STL B17 now requires 54mm flat plate restrictor; B18C Type R variants move to 54mm restrictor, weight chart baseline. · STL Mazda Miata removes maximum displacement limit; minimum weight corrected to unspecified figure.showhide
AS Request to add SMG to 9.1.6.B.1 AS Intent #27140cars addedaddedAS Spec Mustang (SMG) added as Restricted Prep class.
P2 Update Engine Table Line E notes #27414wordingwordingP2 Honda K20A-FD2 non-composite chassis intake restrictor note clarified; restrictor implementation date removed.
STL Request to Classify Spec MX-5 Challenge in STL #27399cars addedaddedSTL adds Mazda Spec MX-5 Challenge, 2000cc displacement, 2500 lb minimum weight, with mandatory Roush, Penske, Eibach, and other specified components.
EP Request bodywork for Austin Healey Bugeye Sprite MK1 #27106aeroaddedaeroFP and HP Austin-Healey Sprite Mk I / MG Midget may replace rear bodywork aft of cockpit with alternate material stock-appearing components.
EP Request to classify the GMX5 2019 #27263cars addedaddedEP Mazda MX-5 Global Cup classification updated to include 2019 model year.
EP level one susp. component rule #27270wordingwordingProduction classes: suspension rule clarified to specify spindles, hubs, bushings, bearings, and ball joints unrestricted.
EP Clarification of Carb Rules - Prep 1 #27300wordingwordingProduction carburetor and fuel injection rules clarified: permitted optional carburetors listed, Weber and auto-type substitutions specified, fuel injection throttle body and butterfly dimensions detailed, intake manifold port extension pr…
EP Clarification of Carb Rules - Prep 2 #27301inductioninductionEP, FP, HP carburetors: jets, needles, metering rods, needle valves unrestricted; choke parts removable; stock or optional Weber 40 DCN permitted; Weber types, auto types listed.
P2 Update P2 Engine Table spec lines to reflect 3/1/2019 #27254engineslowerengineP2 motorcycle engines: Stock restrictor to 35mm, Modified to 34mm; weights up to 1025 and 1125 lbs respectively. B.5 restrictor to 33mm, weight to 1185 lbs.
AS Request Ride Height Clarification #26598wordingwordingAS class ride height minimum clarified: five inches measured at rocker panel, excluding seams and stock effects.
EP Request Miata Eligibility - 2003 #27121cars addedaddedEP Mazda MX-5/Miata model years expand from 1999-2002 to 1999-2005.
P2 E&O Transmissions #27006engineslowerengineP2 cars limited to power application on maximum two wheels.
STL Request clarification for manifold and throttle in STU #27004wordingwordingSTU allows alternate intake manifolds on case-by-case basis; stock throttle device and manifold otherwise required.
P2 Request to restrict all cars #26246weightslowerweightP2 Enterprise minimum weight increased to 1375 lbs.; peak horsepower of sealed ESR engine reduced per CRB specification.
AS Request to Revert to 2017 Weights #25885weightfasterweightAS Ford Mustang 79-93 non-Cobra drops 100 lbs to 3150; over 313 CID Cobra drops 100 lbs to 3450.
STL Request Restrictor Plate correction #26779enginefasterengineSTL Acura/Honda B18 except C engine restrictor increased from 53mm to 54mm flat plate.
EP Allow Firewall Modification for Fitment of 13B into RX8 #26726engineaddedengineEP Mazda RX-8 firewall may be modified for 13B engine fitment and must be sealed.
STL Request Ride Height Clarification #26597wordingwordingSTL and STU ride height measurement clarified: lowest rocker panel point without driver, excluding pinch weld.
EP Rollcenter Correction Clarification #25873wordingaddedEP, FP, HP: clarified that tapered holes in ball joints can be reamed for bolt conversion, and wheel bearings and hubs unrestricted on all axles.
EP Hardtops #26476aeroaddedaeroEP open cars may now use aftermarket hardtops if OEM-appearance and non-carbon-fiber; specific model allowances removed as redundant.
EP Request for Competition Adjustment for 2nd Generation RX7 #25935weight -50 lbsfasterweightEP Mazda RX-7 12A and 13B (79-85) lose up to 75 lbs; 13B (86-91) loses up to 79 lbs across three weight classes.
P2 Change Engine Table Lines B.1 & B.5 #25777inductionslowerinductionP2 stock and modified engines get smaller restrictors (35.0mm, 34.0mm, 33.0mm) and heavier minimums (1025, 1125, 1185 lbs).
P2 Change Line A.1 restrictor size #26429engineslowerengineP2 Line A.1 restrictor reduced from 40mm to 38mm.
STL Request to reduce weight of RX8 with Renesis rotary #25781weight -100 lbsfasterweightSTL Mazda Renesis minimum weight reduced to 2700 lbs.
STL Request for Open Brake Pads On Mazda MX-5 Cup NC #25821otheraddedSTL Mazda MX-5 Cup brake pad compound now open.
STL Request to clarify B18C1 GSR Honda B motor table #26209cars addedaddedSTL adds Acura/Honda B18C1 GSR with 1797cc displacement, 54mm flat plate restrictor required, porting outside 1" allowance prohibited.
STL Port Matching #26415enginefasterengineSTL Mazda 12 and 13B now permit port matching; porting ban removed.
AS SMG Mustang eligibility in American sedan #26224cars addedaddedAS adds Spec Mustang SMG classification with 107.1 wheelbase, 3.73 gears, 355mm front and 300mm rear brakes.
P2 Request to Allow 1345cc Hayabusa Engines for Spec Line P2 Cars #25595cars addedaddedP2 Spec Line cars now allow 1345cc Hayabusa stock engines at 1050 lb minimum with 30mm restrictor.
P2 Change CN inlet restrictor implementation date #25816wordingwordingP2 Group CN Honda K20A-FD2 55mm intake restrictor implementation delayed from 1 January to 3 March 2019.
P2 Clarify Honda K20A-FD2 parts requirement #25950engineslowerengineP2 Honda K20A-FD2 Group CN must use stock intake manifold, 64mm throttle, 55mm restrictor at 1500 lbs minimum.
STL Request to equalize FPR Reduction on all B-Series Vtec Engines #24746enginefasterengineSTL B17 now requires 54mm flat plate restrictor; B18C Type R variants move to 54mm restrictor, weight chart baseline.
STL Request E&O for Mazda Miata Spec Line #25955otherunclearSTL Mazda Miata removes maximum displacement limit; minimum weight corrected to unspecified figure.
Every event the class ran, at any track, oldest to newest on the chart and newest first in the table. Each point is the class's best lap as a share of P2's best on the same day: the weather and the day cancel out, so one figure compares across years where lap times cannot; a class that suits one track more than another still reads differently there. It still moves when the yardstick's own balance changes or its field thins, and an event the yardstick did not run has no point. A best from fewer than three cars is greyed. The rule changes that took effect between two events are folded between their rows.