BoP Lab / Classes / SRF3
SRF3 vs SM vs FB vs EP pace at every track
Lap times across years say as much about the weather as the class. % of SRF3 is each class's best lap as a share of SRF3's on the same day, so the conditions drop out: 100% is level, less is quicker, and a move in it is the class getting faster or slower against the field.
Quickest here: SRF3 1:34.363 John Black, Runoffs 2016 qualifying · SM 1:40.514 Justin Hille, Runoffs 2016 qualifying · FB 1:19.886 Alex Mayer, Runoffs 2016 qualifying · EP 1:33.847 Michael Galati, Runoffs 2016 qualifying
| Event | SRF3 | SM | FB | EP | ||||||||||||||||
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| Qual best | Race best | Trap | Qual best | Race best | Trap | vs SRF3 | % of SRF3 | Qual best | Race best | Trap | vs SRF3 | % of SRF3 | Qual best | Race best | Trap | vs SRF3 | % of SRF3 | |||
| Road America Runoffs 20262026-09-28 | 2:27.443Tyler Stephens · fastest of 44 · top 5 within 0.3s-0.783s (-0.53%) | 2:29.257Peyton Long · fastest of 42 · top 5 within 0.3s-0.582s (-0.39%) | 134.1Bobby Sak+0.4 mph (+0.3%) | 2:42.173Brett Kowalski · fastest of 34 · top 5 within 0.3s-0.938s (-0.58%) | 2:42.725Francisco Barroso · fastest of 35 · top 5 within 0.2s-1.705s (-1.04%) | 119.6Wyatt Couch+0.3 mph (+0.3%) | +13.468squal +14.730s | 109.0%qual 110.0% | 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%) | -1.388squal +1.796s | 99.1%qual 101.2% | |||||||
25 rule changes (SRF3: 2, SM: 2, EP: 21)5 engine · 4 induction · 4 weight · 2 aero · 2 cars added · 6 wording · 2 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. · SM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361. · 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. · SM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. · SRF3 spark plugs limited to NGK LTR7IX-11 P/N G301041 only; washers and sealing rings prohibited. · 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. · SRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted.show
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| Road America Runoffs 20252025-09-29 | 2:28.226Bobby Sak · fastest of 43 · top 5 within 0.6s+0.453s (+0.31%) | 2:29.839Morgan Burkhard · fastest of 42 · top 5 within 0.3s+1.710s (+1.15%) | 133.7Bobby Sak-1.5 mph (-1.1%) | 2:43.111Bobby Gossett · fastest of 32 · top 5 within 0.3s+2.005s (+1.24%) | 2:44.430Kyle Greenhill · fastest of 28 · top 5 within 0.3s+2.944s (+1.82%) | 119.3Francisco Barroso-0.6 mph (-0.5%) | +14.591squal +14.885s | 109.7%qual 110.0% | 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%) | -1.083squal -0.933s | 99.3%qual 99.4% | |||||||
21 rule changes (SRF3: 3, SM: 4, EP: 14)6 weight · 4 induction · 1 cars added · 1 engine · 5 wording · 4 other · SRF3 adds oil cooler options P/N G480503 and P/N G1148500; brake rule restructured to list Hawk Blue pads, Wilwood rotor, caliper kit, master cylinder options. · 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. · SMX drivers must submit data acquisition files on time or face suspension and $250 fine. · SMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines. · SM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only. · 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. · SRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only. · SRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward. · 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. · SMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation. · 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.show
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| Road America Runoffs 20242024-10-01 | 2:27.773Denny Stripling · fastest of 57 · top 5 within 0.3s-2.013s (-1.34%) | 2:28.129S Sandy Satullo III · fastest of 52 · top 5 within 0.7s-2.909s (-1.93%) | 135.2Denny Stripling+3.4 mph (+2.6%) | 2:41.106Ethan Goulart · fastest of 49 · top 5 within 0.5s-1.103s (-0.68%) | 2:41.486Brett Kowalski · fastest of 43 · top 5 within 0.3s-2.262s (-1.38%) | 119.9Alex Bertagnoli-1.4 mph (-1.2%) | +13.357squal +13.333s | 109.0%qual 109.0% | 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%) | -0.260squal -0.970s | 99.8%qual 99.3% | |||||||
28 rule changes (SRF3: 10, SM: 4, EP: 14)8 weight · 3 cars added · 2 suspension & brakes · 1 engine · 1 induction · 1 removed · 1 tyres & wheels · 7 wording · 4 other · SRF3 air filter rule removes K&N RC-9160 option, specifies Weems P/N WM301020 only. · SRF Wilwood vented rotor minimum thickness increases to 13.25mm, 0.522 inches. · SRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front. · SMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification. · SM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01. · SMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only. · SM and SMX now allow an alternate shifter bushing at the bottom of the shift lever. · SRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement. · HP Volkswagen Golf and Jetta 85-92 track correction: front 1537 mm (60.5 in.), rear 1529 mm (60.2 in.). · SRF wet tyres: front P185/60R13 H20 or W2 and rear P205/60R13 H20 or W2 removed; front P185/65R13 W2 and rear P205/60R13 W2 now required. Hoosier decal placement specified. · 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. · SRF3 alternator pulley minimum weight drops from 12 to 11 oz, adds P/N G902131 six-row option. · 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. · 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. · SRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch. · SRF brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24, with SCCA Enterprises P/N 180427A pigtail and strobing rain light kit. · SRF adds mandatory front brake ducts 12–36 inches, throttle pedal heel-toe extension, braided stainless flex lines, camber limit 5.0 degrees, radiator opening height 3½ ± ½ inches, rear shift cable clamp P/N WM302007A. · 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. · SRF radiator options expanded: Enterprises P/N 480465 with baffle 480464, 480466, or Automotive 1R698 and CU698 allowed if cross-reference equivalent.show
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| Virginia International Raceway Runoffs 20232023-09-23 | 2:03.842Morgan Burkhard · fastest of 40 · top 5 within 0.2s+0.126s (+0.10%) | 2:04.911David Ogburn · fastest of 39 · top 5 within 0.3s-17.155s (-12.08%) | 134.5Bobby Sak+0.1 mph (+0.0%) | 2:14.986Danny Steyn · fastest of 52 · top 5 within 0.1s+0.322s (+0.24%) | 2:16.229Julian DaCosta · fastest of 46 · top 5 within 0.3s-2.878s (-2.07%) | 120.3Jim Drago+1.1 mph (+0.9%) | +11.318squal +11.144s | 109.1%qual 109.0% | 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%) | -0.861squal -0.627s | 99.3%qual 99.5% | |||||||
18 rule changes (SRF3: 4, SM: 1, EP: 13)3 engine · 2 cars added · 2 tyres & wheels · 2 weight · 1 induction · 1 removed · 1 suspension & brakes · 4 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. · EP Porsche 914-6 2.0L intake valve increased to 2.0 mm, exhaust valve corrected to 38.0 mm. · SRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance. · SRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13. · EP BMW Z3 2.5L flat plate intake restrictor reduced from 58mm to 56mm, both throttle bodies. · SRF removes 1985 Renault Alliance solid front rotor option; restrictor sizes decrease 1mm for newer Kawasaki and multi-brand engines; minimum weights increase to 1100 lbs. · SRF3 alternate dash panel P/N 180100 or 180101 moved from optional to required bodywork section. · 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. · SM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore.show
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| Virginia International Raceway Runoffs 20222022-09-24 | 2:03.716Franklin Futrelle · fastest of 44 · top 5 within 0.6s-0.908s (-0.73%) | 2:22.066Franklin Futrelle · fastest of 40 · top 5 within 1.2s+17.311s (+13.88%) | 134.5David Ogburn+2.1 mph (+1.6%) | 2:14.664Danny Steyn · fastest of 60 · top 5 within 0.2s+0.112s (+0.08%) | 2:19.107Travis Wiley · fastest of 58 · top 5 within 0.9s+2.648s (+1.94%) | 119.2Jonathan Neudorf-0.6 mph (-0.5%) | -2.959squal +10.948s | 97.9%qual 108.8% | 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%) | +8.789squal -1.390s | 106.2%qual 98.9% | |||||||
25 rule changes (SRF3: 3, SM: 1, EP: 21)4 engine · 3 cars added · 3 induction · 3 weight · 1 aero · 1 suspension & brakes · 1 tyres & wheels · 6 wording · 3 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. · EP Subaru BRZ title updated to include model years 13–20; Toyota 86/Scion FR-S title likewise updated to 13–20. · SRF tire rule wording clarified: tires must be run as delivered. · SRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified. · 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. · 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. · SM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation. · 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. · 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. · SRF wet tyres front P185/65R13 W2 option added; air box clarified as-delivered; SRF3 restrictor plate G301048 mandatory Jan 1 2022; P2 motorcycle engines up to 1005cc with 35mm restrictor, 2009+ stock 1075 lbs, 2008 stock 1025 lbs, modifie… · 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.show
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| Indianapolis Motor Speedway Runoffs 20212021-09-25 | 1:49.520Franklin Futrelle · fastest of 84 · top 5 within 0.5s-0.304s (-0.28%) | 1:50.095John Black · fastest of 82 · top 5 within 0.2s+0.313s (+0.29%) | 132.1Matthew Horst | 1:57.695Brian Henderson · fastest of 90 · top 5 within 0.5s-0.611s (-0.52%) | 1:58.837Brian Henderson · fastest of 88 · top 5 within 0.3s-0.263s (-0.22%) | 119.8Kyle Greenhill | +8.742squal +8.175s | 107.9%qual 107.5% | 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 | -0.167squal -1.339s | 99.8%qual 98.8% | |||||||
21 rule changes (SRF3: 6, SM: 1, EP: 14)6 cars added · 4 weight · 1 engine · 1 induction · 1 tyres & wheels · 5 wording · 3 other · 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. · SRF wet tyres add Hoosier W2 option alongside existing H20 from October 4, 2021. · SRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive. · SRF seal requirements clarified: seals now must be on driveline components in designated locations; unsealed components removed and inspected by CSR or Enterprises rather than engine shipped for testing. · 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. · SRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz. · 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. · 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. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. · SRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement. · 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. · SRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified.show
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| Road America Runoffs 20202020-10-02 | 2:29.786TJ Acker · fastest of 59 · top 5 within 0.5s | 2:31.038Justin Hille · fastest of 55 · top 5 within 0.2s | 131.9Charles Russell Turner | 2:42.209Kyle Greenhill · fastest of 77 · top 5 within 0.5s | 2:43.748Preston Pardus · fastest of 75 · top 5 within 1.0s | 121.3Kyle Greenhill | +12.710squal +12.423s | 108.4%qual 108.3% | 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 | -1.991squal -2.464s | 98.7%qual 98.4% | |||||||
23 rule changes (SRF3: 7, SM: 2, EP: 14)3 engine · 2 cars added · 2 induction · 2 suspension & brakes · 2 weight · 1 tyres & wheels · 10 wording · 1 other · HP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches. · SM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A. · EP BMW Z3 2.5L cylinder head casting 1738400 permitted with iron block castings 1748933 or 1738566. · SM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure. · 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. · SRF3 shocks no longer require the same brand in all positions; only SCCA P/N 280407 bump stops allowed, one per shock, all must be sealed by Enterprises. · 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. · SRF3 bump stop must be SCCA P/N 280407, no modifications, optional, maximum one per shock. · SRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020. · 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. · Mazda Miata models EP and FP throttle body specified 55mm, brake rotor thickness figures removed. · SRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024. · EP, FP, HP cylinder head rules reorganized for clarity; no performance change. · SRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers. · SRF front nose weight minimum reduced from 35 to 32 lbs. · SRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points.show
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| Virginia International Raceway Runoffs 20192019-10-05 | 2:04.624Brian Schofield · fastest of 54 · top 5 within 0.6s | 2:04.755Bobby Sak · fastest of 53 · top 5 within 0.3s | 132.4Bobby Sak | 2:14.552Todd Buras · fastest of 60 · top 5 within 0.2s | 2:16.459Elivan Goulart · fastest of 56 · top 5 within 0.4s | 119.8Jim Drago | +11.704squal +9.928s | 109.4%qual 108.0% | 1:54.469Pete Frost · only car | 1:57.688Pete Frost · only car | 145.9Pete Frost | -7.067squal -10.155s | 94.3%qual 91.9% | 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 | -3.124squal -3.637s | 97.5%qual 97.1% | ||
17 rule changes (SRF3: 3, SM: 4, EP: 10)4 aero · 2 cars added · 1 engine · 1 induction · 1 weight · 5 wording · 3 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. · SRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102. · SRF3 multi-piece nose assembly approved for use; no other nose modifications allowed. · EP Mazda RX-8 firewall may be modified for 13B engine fitment and must be sealed. · SRF3 brakes now accept Hawk Blue 9012 pads P/N 801993 only; Wilwood vented rotor P/N 800065 minimum 13.25mm as delivered; caliper bushings P/N 1196185 A or B permitted. Shock absorbers: Penske P/N 280396 only, sealed, with SCCA bump rubber… · 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. · SM fuel pump and filter now permitted as Mazda or OEM equivalent part. · SM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified. · SM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted. · SM tire tread protrusion language removed from GCR 9.1.7.C.5.show
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| Sonoma Raceway Runoffs 20182018-10-10 | 1:46.117Robeson Clay Russell · fastest of 36 · top 5 within 0.5s | 1:47.053TJ Acker · fastest of 35 · top 5 within 0.2s | 110.2Steve Fogg | 1:54.355Ken Sutherland · fastest of 48 · top 5 within 0.7s | 1:55.278Michael Carter · fastest of 48 · top 5 within 0.3s | 102.2Danny Steyn | +8.225squal +8.238s | 107.7%qual 107.8% | 1:28.612J R Osborne · fastest of 7 · top 5 within 3.3s | 1:31.189J R Osborne · fastest of 7 · top 5 within 3.7s | 140.5J R Osborne | -15.864squal -17.505s | 85.2%qual 83.5% | 1:45.828Glen McCready · fastest of 18 · top 5 within 4.3s | 1:46.518Glen McCready · fastest of 16 · top 5 within 2.8s | 106.5Aaron Downey | -0.535squal -0.289s | 99.5%qual 99.7% | ||
| No rule changes on record between these events | ||||||||||||||||||||
| Indianapolis Motor Speedway Runoffs 20172017-09-25 | 1:49.824John Black · fastest of 101 · top 5 within 0.5s | 1:49.782Tray Ayres · fastest of 94 · top 5 within 0.4s | 1:58.306Chris Haldeman · fastest of 86 · top 5 within 0.5s | 1:59.100Michael Gagliardo · fastest of 83 · top 5 within 0.6s | +9.318squal +8.482s | 108.5%qual 107.7% | 1:33.746Gary Hickman · fastest of 18 · top 5 within 3.3s | 1:33.702Alex Mayer · fastest of 17 · top 5 within 3.0s | -16.080squal -16.078s | 85.4%qual 85.4% | 1:49.597Matt Reynolds · fastest of 44 · top 5 within 1.2s | 1:50.396Matt Reynolds · fastest of 45 · top 5 within 0.5s | +0.614squal -0.227s | 100.6%qual 99.8% | ||||||
| No rule changes on record between these events | ||||||||||||||||||||
| Mid-Ohio Sports Car Course Runoffs 20162016-09-19 | 1:34.363John Black · fastest of 41 · top 5 within 0.5s | 1:34.947Cliff White · fastest of 39 · top 5 within 0.3s | 1:40.514Justin Hille · fastest of 45 · top 5 within 0.3s | 1:40.764Michael Carter · fastest of 44 · top 5 within 0.3s | +5.817squal +6.151s | 106.1%qual 106.5% | 1:19.886Alex Mayer · fastest of 10 · top 5 within 1.5s | 1:21.015Jeremy Hill · fastest of 10 · top 5 within 1.2s | -13.932squal -14.477s | 85.3%qual 84.7% | 1:33.847Michael Galati · fastest of 25 · top 5 within 0.8s | 1:34.266Michael Galati · fastest of 23 · top 5 within 1.3s | -0.681squal -0.516s | 99.3%qual 99.5% | ||||||
| No rule changes on record between these events | ||||||||||||||||||||
| Daytona International Speedway Runoffs 20152015-09-21 | 2:08.557Kerry Jacobsen · fastest of 29 · top 5 within 1.1s | 2:10.215Chad Galloway · fastest of 29 · top 5 within 0.3s | 2:18.661Andrew Carbonell · fastest of 62 · top 5 within 0.6s | 2:24.067Todd Lamb · fastest of 59 · top 5 within 0.8s | +13.852squal +10.104s | 110.6%qual 107.9% | 1:50.711J R Osborne · fastest of 20 · top 5 within 1.1s | 1:51.616J R Osborne · fastest of 19 · top 5 within 2.1s | -18.599squal -17.846s | 85.7%qual 86.1% | 2:03.794Kip Van Steenburg · fastest of 29 · top 5 within 3.2s | 2:05.109Kip Van Steenburg · fastest of 28 · top 5 within 3.3s | -5.106squal -4.763s | 96.1%qual 96.3% | ||||||
By track
| Track | Events | Typical % of SRF3 | Best | Latest |
|---|---|---|---|---|
| Road America | 4 | 100.0% | 100.0%Runoffs 2020 | 100.0%Runoffs 2026 |
| Virginia International Raceway | 3 | 100.0% | 100.0%Runoffs 2019 | 100.0%Runoffs 2023 |
| Indianapolis Motor Speedway | 2 | 100.0% | 100.0%Runoffs 2017 | 100.0%Runoffs 2021 |
| Daytona International Speedway | 1 | 100.0% | 100.0%Runoffs 2015 | 100.0%Runoffs 2015 |
| Mid-Ohio Sports Car Course | 1 | 100.0% | 100.0%Runoffs 2016 | 100.0%Runoffs 2016 |
| Sonoma Raceway | 1 | 100.0% | 100.0%Runoffs 2018 | 100.0%Runoffs 2018 |
About this data
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 SRF3's best on the same day: the weather, the track and its configuration cancel out, so one figure compares across tracks and years where lap times cannot. It still moves when the yardstick's own balance changes or its field thins, and an event the yardstick did not run has no point. A best from fewer than three cars is greyed. The rule changes that took effect between two events are folded between their rows.