Lap times across years say as much about the weather as the class. % of P1 is each class's best lap as a share of P1'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:P1 100.0% of P1 Gianpaolo Ciancimino, Daytona International Speedway Runoffs 2015 race · FB 101.0% of P1 J R Osborne, Sonoma Raceway Runoffs 2018 qualifying · EP 113.3% of P1 Kip Van Steenburg, Daytona International Speedway Runoffs 2015 qualifying
P1FBEPsolid race · dashed qualifying · slower is lower
P1FBEPsolid race · dashed qualifying · each class's best lap as a share of P1's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
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%)
21 rule changes (EP: 21)4 induction · 4 weight · 3 engine · 2 aero · 2 cars added · 5 wording · 1 other · 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. · EP Honda S2000 gains permission to use Mugen hardtop P/N 0000-04-2312 or aftermarket equivalent. · 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. · EP BMW 325i/is E30 fuel injection throttle body specified as 60mm diameter. · 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. · 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
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.
EP Honda S2000 Hardtop #40138aeroaddedaeroEP Honda S2000 gains permission to use Mugen hardtop P/N 0000-04-2312 or aftermarket equivalent.
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.
EP Request to Update E30 BMW Throttle Body Diameter Verbiage #39363wordingwordingEP BMW 325i/is E30 fuel injection throttle body specified as 60mm diameter.
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.
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.
2:27.293Jon 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%)
14 rule changes (EP: 14)6 weight · 4 induction · 1 cars added · 1 engine · 1 wording · 1 other · 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. · 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. · 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. · 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. · 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. · 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
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.
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.
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.
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.
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.
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.
2:00.476Chip Romer · fastest of 12 · top 5 within 1.5s-0.625s (-0.52%)
2:00.418Matt Romer · fastest of 9 · top 5 within 2.1s-1.452s (-1.19%)
168.3Jason Miller+8.7 mph (+5.4%)
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%)
+27.451squal +26.327s
122.8%qual 121.9%
20 rule changes (P1: 6, EP: 14)9 weight · 3 cars added · 1 induction · 1 removed · 6 wording · HP Volkswagen Golf and Jetta 85-92 track correction: front 1537 mm (60.5 in.), rear 1529 mm (60.2 in.). · 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. · P1 engine approval process wording clarified; unspecified engines need case-by-case Board review. · HP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve 83-88, Scirocco 1588. · P1 removes redundant effective date language from ECU stall prohibition rule. · P1 Honda K20A-FD2 engine terminology corrected from 'spec' to proper series designation; FIA certification documentation requirement removed. · 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. · 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. · P1 Engine Table line H restrictor grows to 32 mm, weight rises to 1450 lbs; line I restrictor to 31 mm, weight to 1475 lbs. · P1 Group CN Honda K20A-FD2 removes engine modification restrictions; CRB may add intake restrictor if needed. · 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.showhide
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.).
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.
P1 Update GCR section 9.1.8.B.J.7 #35907wordingwordingP1 engine approval process wording clarified; unspecified engines need case-by-case Board review.
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.
P1 Remove redundant effective date language in GCR 9.1.8.B.J.4 #35693wordingwordingP1 removes redundant effective date language from ECU stall prohibition rule.
P1 Correct engine series terminology #35694wordingwordingP1 Honda K20A-FD2 engine terminology corrected from 'spec' to proper series designation; FIA certification documentation requirement removed.
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.
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.
P1 Adjust restrictors and weights for Engine Table lines H and I #35229weightslowerweightP1 Engine Table line H restrictor grows to 32 mm, weight rises to 1450 lbs; line I restrictor to 31 mm, weight to 1475 lbs.
P1 Revise Group CN Honda K20A-FD2 Spec Line #35337wordingunclearP1 Group CN Honda K20A-FD2 removes engine modification restrictions; CRB may add intake restrictor if needed.
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.
1:42.602Todd Vanacore · fastest of 10 · top 5 within 0.9s+1.001s (+0.99%)
1:44.329Todd Vanacore · fastest of 9 · top 5 within 0.7s-9.766s (-8.56%)
158.5Jason Miller+1.2 mph (+0.8%)
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%)
+19.721squal +20.613s
118.9%qual 120.1%
20 rule changes (P1: 7, EP: 13)3 engine · 2 aero · 2 cars added · 1 induction · 1 removed · 1 suspension & brakes · 1 weight · 7 wording · 2 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. · FP and HP Sprite and Spitfire 1500 intake valve size corrected to 36.6 mm, removing prior decimal specifications. · P1 SIR testing: vehicle deemed compliant if it stalls within 3 seconds of the stall test. · P1 intake restrictor rule clarified: flat plate, venturi, or Single Inlet Restrictor required; all intake air must pass through. · P1 ducted air rule clarified: top-exit ducted air must pass through heat exchanger, except cockpit opening and engine bay vents. · EP Porsche 914-6 2.0L intake valve increased to 2.0 mm, exhaust valve corrected to 38.0 mm. · EP BMW Z3 2.5L flat plate intake restrictor reduced from 58mm to 56mm, both throttle bodies. · P1 aero height limit, front/rear overhang, and cockpit dimensions corrected to metric-inch equivalents. · P1 suspension covers must have symmetrical upper and lower surfaces, no airfoil cross-sections or angled downforce. · 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. · P1 aerodynamic devices may not extend more than 1cm below lower surfaces rear of front axle; body panels covering suspension must not be airfoil-shaped or create downforce. · P1 forced induction prohibited: turbocharging and supercharging not allowed.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.
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.
P1 SIR Testing #34354wordingwordingP1 SIR testing: vehicle deemed compliant if it stalls within 3 seconds of the stall test.
P1 E&O Single Inlet Restrictor abbreviation, etc. #34369wordingwordingP1 intake restrictor rule clarified: flat plate, venturi, or Single Inlet Restrictor required; all intake air must pass through.
P1 E&O Clean up ducted air provision #34410wordingwordingP1 ducted air rule clarified: top-exit ducted air must pass through heat exchanger, except cockpit opening and engine bay vents.
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.
EP Investigate Parity of Z3 #33343inductionslowerinductionEP BMW Z3 2.5L flat plate intake restrictor reduced from 58mm to 56mm, both throttle bodies.
P1 E&O - Correct dimensional equivalents #34018wordingwordingP1 aero height limit, front/rear overhang, and cockpit dimensions corrected to metric-inch equivalents.
P1 November 2022 Rules Clarification for Suspension Covers #33615aerosloweraeroP1 suspension covers must have symmetrical upper and lower surfaces, no airfoil cross-sections or angled downforce.
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.
P1 Clarify body panel coverage of suspension components #33318aeroaeroP1 aerodynamic devices may not extend more than 1cm below lower surfaces rear of front axle; body panels covering suspension must not be airfoil-shaped or create downforce.
P1 E&O clarification regarding forced induction #33123engineremovedengineP1 forced induction prohibited: turbocharging and supercharging not allowed.
1:41.601Todd Slusher · fastest of 9 · top 5 within 2.3s-1.073s (-1.05%)
1:54.095John Mcaleer · fastest of 9 · top 5 within 1.4s+10.597s (+10.24%)
157.2Jason Miller+1.3 mph (+0.8%)
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%)
+36.760squal +20.725s
132.2%qual 120.4%
24 rule changes (P1: 3, EP: 21)6 engine · 3 cars added · 3 induction · 3 weight · 1 aero · 1 suspension & brakes · 1 tyres & wheels · 5 wording · 1 other · 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. · P1 motorcycle-based engines with individual throttle bodies must use flat plate intake restrictors within 4 inches of primary butterfly. · 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. · P1 bodywork rules clarified: cycle fenders prohibited, side body minimum height at front axle centerline, air ducting for downforce banned. · 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. · 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. · 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. · 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. · P1 2-cycle 6-cylinder maximum displacement increases to 1725 cc, restrictor shrinks to 40mm, minimum weight drops to 1275 lbs. · 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. · 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
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.
P1 Clarify authorization to use flat plate intake restrictor #32964engineaddedengineP1 motorcycle-based engines with individual throttle bodies must use flat plate intake restrictors within 4 inches of primary butterfly.
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.
P1 E&O Clarification of Bodywork Rules #32468wordingwordingP1 bodywork rules clarified: cycle fenders prohibited, side body minimum height at front axle centerline, air ducting for downforce banned.
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.
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.
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.
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.
P1 Displacement & Weight Change Request for 2-Cycle 6 Cylinder #31609enginefasterengineP1 2-cycle 6-cylinder maximum displacement increases to 1725 cc, restrictor shrinks to 40mm, minimum weight drops to 1275 lbs.
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.
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.
1:29.011Lee Alexander · fastest of 13 · top 5 within 2.5s-1.783s (-1.96%)
1:29.225Lee Alexander · fastest of 12 · top 5 within 3.5s-2.274s (-2.49%)
160.1Jason Miller
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
+20.703squal +19.170s
123.2%qual 121.5%
25 rule changes (P1: 11, EP: 14)7 cars added · 4 weight · 2 engine · 1 induction · 9 wording · 2 other · P1 creates separate spec lines H and I for 2000cc and 2300cc engines at 1400 and 1445 lbs minimum weight respectively. · P1 Staudacher may run 950 lbs minimum weight with 38.5mm flat plate intake restrictor, removing prior weight-linked restrictor rule. · 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. · P1 adds 1355cc motorcycle-based engine line C at 1075 lbs minimum weight, no restrictor required. · 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. · EP, FP, HP clarify percentage weight penalties sum before applying to base weight, round to nearest pound. · 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. · P1 cockpit opening section allows tonneau covers to meet minimum dimensions; wording clarified on equipment attachment. · P1 Staudacher 1005cc homologated before 1-1-2014 may run 38.5mm flat plate intake restrictor at 950 lbs minimum weight. · P1 Spec Line C: FPIR not required at 1150 lbs, 1355cc max may run without FPIR at 1075 lbs. Spec Line G: up to 2000cc runs 30mm SIR at 1400 lbs, 2300cc runs 30mm SIR at 1445 lbs. · P1 classes B, C, D maximum valves per cylinder set to 4, previously unspecified. · 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. · P1 Spec Line A clarifies carburetor induction only, one per cylinder, balance tubes not allowed. · P1 Spec Line H notes clarify peripheral port or bridgeport allowed; wording only. · P1 Elan DP02-spec Mazda MZR sealed engine option removed effective 3/1/2021. · P1 Engine Table Spec Lines C and G change 'inlet restrictor' to 'intake restrictor' terminology. · EP Austin-Healey 3000 gains option to use TR-6 front calipers and discs as alternate. · 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.showhide
P1 Move 2000cc and 2300cc engine options to individual spec lines #31012cars addedaddedP1 creates separate spec lines H and I for 2000cc and 2300cc engines at 1400 and 1445 lbs minimum weight respectively.
P1 E&O Spec Line B notes #31095wordingwordingP1 Staudacher may run 950 lbs minimum weight with 38.5mm flat plate intake restrictor, removing prior weight-linked restrictor rule.
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.
P1 Add 1355cc spec line #30890cars addedaddedP1 adds 1355cc motorcycle-based engine line C at 1075 lbs minimum weight, no restrictor required.
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.
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.
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.
P1 E&O tonneau cover provision in cockpit opening section #30458wordingwordingP1 cockpit opening section allows tonneau covers to meet minimum dimensions; wording clarified on equipment attachment.
P1 Update Spec Line B Notes #30498wordingwordingP1 Staudacher 1005cc homologated before 1-1-2014 may run 38.5mm flat plate intake restrictor at 950 lbs minimum weight.
P1 Update Spec Lines C and G notes #30499wordingwordingP1 Spec Line C: FPIR not required at 1150 lbs, 1355cc max may run without FPIR at 1075 lbs. Spec Line G: up to 2000cc runs 30mm SIR at 1400 lbs, 2300cc runs 30mm SIR at 1445 lbs.
P1 E&O Maximum Valves Per Cylinder #30559engineengineP1 classes B, C, D maximum valves per cylinder set to 4, previously unspecified.
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.
P1 Clean up Spec Line A notes section #30424wordingwordingP1 Spec Line A clarifies carburetor induction only, one per cylinder, balance tubes not allowed.
P1 Clean up Spec Line H notes section #30425wordingwordingP1 Spec Line H notes clarify peripheral port or bridgeport allowed; wording only.
P1 E&O restrictor terminology #30285wordingwordingP1 Engine Table Spec Lines C and G change 'inlet restrictor' to 'intake restrictor' terminology.
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.
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.
2:01.101James French · fastest of 18 · top 5 within 1.1s
2:01.870James French · fastest of 17 · top 5 within 1.8s
159.7David Locke
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
+27.177squal +26.221s
122.3%qual 121.7%
18 rule changes (P1: 4, EP: 14)4 engine · 3 induction · 2 cars added · 1 removed · 1 weight · 6 wording · 1 other · HP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches. · EP BMW Z3 2.5L cylinder head casting 1738400 permitted with iron block castings 1748933 or 1738566. · Porsche 911 S 67-68 classified in EP at 1800–1890 lbs, 1991cc opposed 6-cylinder SOHC with 36mm carburetors. · EP BMW 2.8L, 328i E36/E46, and 325i E36 now require iron blocks only; 325i E46 aluminum block removed. · 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. · P1 intake manifolds unrestricted unless engine requires flat plate restrictor; no plenums or balance pipes on restricted individual runner manifolds. · EP Caterham 7 America engine limited to IT prep with specific sections, comp ratio 10.0:1, valve lift .380 inch. · 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. · HP Datsun 1200 carburetor option changes from 26mm to 30mm choke(s) in 40 DCN, DCNF, IDF. · P1 sealed 2.0L Elan DP02-spec Mazda option removal date extended from 1/1/2020 to 1/1/2021. · Mazda Miata models EP and FP throttle body specified 55mm, brake rotor thickness figures removed. · P1 sealed 2.0 MZR engine removed effective 1/1/2020; competitors may run it under Spec Line G. · P1 Spec Line F: Restricted 2.0L Group becomes CN-spec Honda K20A-FD2, 2000cc, 1400 lbs minimum. · 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.
EP EP BMW Z3 Rule Clarification #28998wordingwordingEP BMW Z3 2.5L cylinder head casting 1738400 permitted with iron block castings 1748933 or 1738566.
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.
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.
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.
P1 E&O minimum weights and intake manifolds #28731inductioninductionP1 intake manifolds unrestricted unless engine requires flat plate restrictor; no plenums or balance pipes on restricted individual runner manifolds.
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.
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.
EP Request for Help for Datsun 1200 #27934inductionfasterinductionHP Datsun 1200 carburetor option changes from 26mm to 30mm choke(s) in 40 DCN, DCNF, IDF.
P1 Extend date for removing sealed DP02-spec 2.0L option #28046wordingunclearP1 sealed 2.0L Elan DP02-spec Mazda option removal date extended from 1/1/2020 to 1/1/2021.
EP Request to List Mazda Miata Throttle Body Size #27907wordingwordingMazda Miata models EP and FP throttle body specified 55mm, brake rotor thickness figures removed.
P1 Remove sealed DP02-spec 2.0 MZR spec #26753removedremovedP1 sealed 2.0 MZR engine removed effective 1/1/2020; competitors may run it under Spec Line G.
P1 Update Revised Spec Line F #27745engineengineP1 Spec Line F: Restricted 2.0L Group becomes CN-spec Honda K20A-FD2, 2000cc, 1400 lbs minimum.
EP Re-organize Prep2 Cylinder Head Rules for Clarity & Consistency #27661wordingwordingEP, FP, HP cylinder head rules reorganized for clarity; no performance change.
1:42.674Todd Slusher · fastest of 14 · top 5 within 1.5s
1:43.498Todd Slusher · fastest of 13 · top 5 within 1.0s
155.9Jim Devenport
1:54.469Pete Frost · only car
1:57.688Pete Frost · only car
145.9Pete Frost
+14.190squal +11.795s
113.7%qual 111.5%
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
+18.133squal +18.313s
117.5%qual 117.8%
24 rule changes (P1: 14, EP: 10)3 cars added · 2 aero · 1 engine · 1 induction · 1 weight · 15 wording · 1 other · 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. · EP Mazda MX-5/Miata model years expand from 1999-2002 to 1999-2005. · P1 traction control prohibited. · P1 permits mechanical, solenoid, and air-shifters; prohibits electronic pre-selection and multi-wheel power. · P1 minimum bodywork height rule moved and restated with new 115cm aerodynamic part height limit. · P1 consolidates fender louver rules into one section; removes duplicate allowance for louvers and clarifies brake and engine air ducts are permitted. · P1 anti-intrusion panels now allowed anywhere on chassis sides instead of specified locations. · P1 bodywork wording clarified: comfort and safety for driver and passenger or driver only. · EP Mazda RX-8 firewall may be modified for 13B engine fitment and must be sealed. · P1 Engine Table reference cleaned up; no performance change. · P1 Mazda Renesis Rotary engine spec line removed from Engine Table. · 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. · P1 Staudacher and Honda K20A-FD2 engine table wording clarified; no performance change. · 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. · P1 closed cockpit single-seat cars remain prohibited; rule moved from subsection J.5 to B.4. · P1 engine table reference corrected from 'above' to 'below'; ETC/FBW/DBW throttle wording clarified on sensor and fail-safe requirements. · P1 removes TIR inlet restrictor option; deletes requirement for single turbo/supercharger unit with single restrictor. · P1 CN-spec Honda K20A-FD2 clarified: stock OEM parts required, no machining allowed. · P1 engine rules correct grammar and remove head designs from specification table.showhide
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.
EP Request Miata Eligibility - 2003 #27121cars addedaddedEP Mazda MX-5/Miata model years expand from 1999-2002 to 1999-2005.
P1 E&O Transmissions #27098wordingwordingP1 traction control prohibited.
P1 E&O Transmissions #27005otheraddedP1 permits mechanical, solenoid, and air-shifters; prohibits electronic pre-selection and multi-wheel power.
P1 Move minimum height provision to #27031wordingwordingP1 minimum bodywork height rule moved and restated with new 115cm aerodynamic part height limit.
P1 Remove duplicative fender louver provision #27033wordingwordingP1 consolidates fender louver rules into one section; removes duplicate allowance for louvers and clarifies brake and engine air ducts are permitted.
P1 Missing word E&O #26919wordingwordingP1 anti-intrusion panels now allowed anywhere on chassis sides instead of specified locations.
P1 E&O correction to GCR 9.1.8.C.C. #26927wordingwordingP1 bodywork wording clarified: comfort and safety for driver and passenger or driver only.
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.
P1 Clean up reference to engine table #26648wordingwordingP1 Engine Table reference cleaned up; no performance change.
P1 Remove redundant spec line #26692cars addedremovedcars addedP1 Mazda Renesis Rotary engine spec line removed from Engine Table.
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.
P1 Clean Up Engine Table Language #26590wordingwordingP1 Staudacher and Honda K20A-FD2 engine table wording clarified; no performance change.
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.
P1 Move single-seat closed cockpit provision to #26376wordingwordingP1 closed cockpit single-seat cars remain prohibited; rule moved from subsection J.5 to B.4.
P1 Correct errors in GCR section 9.1.8.C.J #26144wordingwordingP1 engine table reference corrected from 'above' to 'below'; ETC/FBW/DBW throttle wording clarified on sensor and fail-safe requirements.
P1 Remove redundant inlet restrictor provisions #25877wordingwordingP1 removes TIR inlet restrictor option; deletes requirement for single turbo/supercharger unit with single restrictor.
P1 Clarify Honda K20A-FD2 parts requirement #25949wordingwordingP1 CN-spec Honda K20A-FD2 clarified: stock OEM parts required, no machining allowed.
P1 Correct GCR section 9.1.8.C.J errors #25966wordingwordingP1 engine rules correct grammar and remove head designs from specification table.
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 P1'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.