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BoP Lab / Classes / SRF

SRF vs FB vs F5 vs FP pace at every track

Lap times across years say as much about the weather as the class. % of SRF is each class's best lap as a share of SRF'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.

Class · click a class to switch, + to compare alongside (up to 4: remove one to add another)
Series
Reference · what % is measured against
Tracks · untick to narrow

Closest to the field: SRF 100.0% of SRF Cliff White, Daytona International Speedway Runoffs 2015 race · FB 81.7% of SRF J R Osborne, Daytona International Speedway Runoffs 2015 race · F5 90.2% of SRF Matthew Strand, Daytona International Speedway Runoffs 2015 race · FP 96.9% of SRF Kevin Ruck, Daytona International Speedway Runoffs 2015 race

1:402:002:202:4011 rule changes between Runoffs 2018 and Runoffs 201911 ▾30 rule changes between Runoffs 2019 and Runoffs 202030 ▾30 rule changes between Runoffs 2020 and Runoffs 202130 ▾34 rule changes between Runoffs 2021 and Runoffs 202234 ▾9 rule changes between Runoffs 2022 and Runoffs 20239 ▾31 rule changes between Runoffs 2023 and Runoffs 202431 ▾19 rule changes between Runoffs 2024 and Runoffs 202519 ▾37 rule changes between Runoffs 2025 and Runoffs 202637 ▾SRF race best at Runoffs 2015: 2:16.700 (Cliff White)SRF race best at Runoffs 2016: 1:37.621 (Todd Harris)SRF race best at Runoffs 2017: 1:53.769 (Todd Harris)SRF qualifying best at Runoffs 2015: 2:14.306 (Cliff White)SRF qualifying best at Runoffs 2016: 1:37.344 (Mike Miserendino)SRF qualifying best at Runoffs 2017: 1:51.573 (Thomas Kirchman)FB race best at Runoffs 2015: 1:51.616 (J R Osborne)FB race best at Runoffs 2016: 1:21.015 (Jeremy Hill)FB race best at Runoffs 2017: 1:33.702 (Alex Mayer)FB race best at Runoffs 2018: 1:31.189 (J R Osborne)FB race best at Runoffs 2019: 1:57.688 (Pete Frost)FB qualifying best at Runoffs 2015: 1:50.711 (J R Osborne)Off the chart: FB qualifying best at Runoffs 2016: 1:19.886 (Alex Mayer)FB qualifying best at Runoffs 2017: 1:33.746 (Gary Hickman)FB qualifying best at Runoffs 2018: 1:28.612 (J R Osborne)FB qualifying best at Runoffs 2019: 1:54.469 (Pete Frost)F5 race best at Runoffs 2015: 2:03.298 (Matthew Strand)F5 race best at Runoffs 2016: 1:29.853 (Steven Thompson)F5 race best at Runoffs 2017: 1:42.860 (Wiley Clinton McMahan)F5 race best at Runoffs 2018: 1:42.491 (David Lapham)F5 race best at Runoffs 2019: 1:57.572 (Wiley Mcmahan)F5 race best at Runoffs 2020: 2:21.391 (James Weida)F5 race best at Runoffs 2021: 1:43.140 (Sven de Vries)F5 race best at Runoffs 2022: 2:21.862 (Sven de Vries)F5 qualifying best at Runoffs 2015: 2:01.824 (W. Clint McMahan)F5 qualifying best at Runoffs 2016: 1:28.528 (Calvin Stewart)F5 qualifying best at Runoffs 2017: 1:43.136 (Wiley Clinton McMahan)F5 qualifying best at Runoffs 2018: 1:41.807 (Jeff Jorgenson)F5 qualifying best at Runoffs 2019: 1:57.361 (Wiley Mcmahan)F5 qualifying best at Runoffs 2020: 2:20.954 (Calvin Stewart)F5 qualifying best at Runoffs 2021: 1:42.619 (Ryan Mayfield)F5 qualifying best at Runoffs 2022: 1:57.689 (James Weida)FP race best at Runoffs 2015: 2:12.419 (Kevin Ruck)FP race best at Runoffs 2016: 1:36.399 (John Walker)FP race best at Runoffs 2017: 1:53.007 (Eric Prill)FP race best at Runoffs 2018: 1:48.481 (Joe Huffaker)FP race best at Runoffs 2019: 2:08.076 (Eric Prill)FP race best at Runoffs 2020: 2:34.033 (Kevin Ruck)FP race best at Runoffs 2021: 1:59.933 (Cliff Ira)FP race best at Runoffs 2022: 2:17.641 (Mason Workman)FP race best at Runoffs 2023: 2:07.787 (Cliff Ira)FP race best at Runoffs 2024: 2:33.246 (Kevin Ruck)FP race best at Runoffs 2025: 2:34.271 (Chris Bovis)FP race best at Runoffs 2026: 2:33.240 (David Strittmatter)FP qualifying best at Runoffs 2015: 2:11.009 (Kevin Ruck)FP qualifying best at Runoffs 2016: 1:35.938 (John Walker)FP qualifying best at Runoffs 2017: 1:52.091 (Eric Prill)FP qualifying best at Runoffs 2018: 1:47.588 (Joe Huffaker)FP qualifying best at Runoffs 2019: 2:07.436 (Eric Prill)FP qualifying best at Runoffs 2020: 2:31.414 (Ethan Shippert)FP qualifying best at Runoffs 2021: 1:51.082 (Craig Chima)FP qualifying best at Runoffs 2022: 2:06.217 (Eric Prill)FP qualifying best at Runoffs 2023: 2:08.248 (Cliff Ira)FP qualifying best at Runoffs 2024: 2:32.327 (Cliff Ira)FP qualifying best at Runoffs 2025: 2:32.395 (David Strittmatter)FP qualifying best at Runoffs 2026: 2:33.275 (Stephen Simonds)Daytona International Speedway · Runoffs 2015R2015Mid-Ohio Sports Car Course · Runoffs 2016R2016Indianapolis Motor Speedway · Runoffs 2017R2017Sonoma Raceway · Runoffs 2018R2018Virginia International Raceway · Runoffs 2019R2019Road America · Runoffs 2020R2020Indianapolis Motor Speedway · Runoffs 2021R2021Virginia International Raceway · Runoffs 2022R2022Virginia International Raceway · Runoffs 2023R2023Road America · Runoffs 2024R2024Road America · Runoffs 2025R2025Road America · Runoffs 2026R2026
SRFFBF5FPsolid race · dashed qualifying · slower is lower
80%85%90%95%100%11 rule changes between Runoffs 2018 and Runoffs 201911 ▾30 rule changes between Runoffs 2019 and Runoffs 202030 ▾30 rule changes between Runoffs 2020 and Runoffs 202130 ▾34 rule changes between Runoffs 2021 and Runoffs 202234 ▾9 rule changes between Runoffs 2022 and Runoffs 20239 ▾31 rule changes between Runoffs 2023 and Runoffs 202431 ▾19 rule changes between Runoffs 2024 and Runoffs 202519 ▾37 rule changes between Runoffs 2025 and Runoffs 202637 ▾SRF race best at Runoffs 2015: 100.0% of SRF's (Cliff White)SRF race best at Runoffs 2016: 100.0% of SRF's (Todd Harris)SRF race best at Runoffs 2017: 100.0% of SRF's (Todd Harris)SRF qualifying best at Runoffs 2015: 100.0% of SRF's (Cliff White)SRF qualifying best at Runoffs 2016: 100.0% of SRF's (Mike Miserendino)SRF qualifying best at Runoffs 2017: 100.0% of SRF's (Thomas Kirchman)FB race best at Runoffs 2015: 81.7% of SRF's (J R Osborne)FB race best at Runoffs 2016: 83.0% of SRF's (Jeremy Hill)FB race best at Runoffs 2017: 82.4% of SRF's (Alex Mayer)FB qualifying best at Runoffs 2015: 82.4% of SRF's (J R Osborne)FB qualifying best at Runoffs 2016: 82.1% of SRF's (Alex Mayer)FB qualifying best at Runoffs 2017: 84.0% of SRF's (Gary Hickman)F5 race best at Runoffs 2015: 90.2% of SRF's (Matthew Strand)F5 race best at Runoffs 2016: 92.0% of SRF's (Steven Thompson)F5 race best at Runoffs 2017: 90.4% of SRF's (Wiley Clinton McMahan)F5 qualifying best at Runoffs 2015: 90.7% of SRF's (W. Clint McMahan)F5 qualifying best at Runoffs 2016: 90.9% of SRF's (Calvin Stewart)F5 qualifying best at Runoffs 2017: 92.4% of SRF's (Wiley Clinton McMahan)FP race best at Runoffs 2015: 96.9% of SRF's (Kevin Ruck)FP race best at Runoffs 2016: 98.7% of SRF's (John Walker)FP race best at Runoffs 2017: 99.3% of SRF's (Eric Prill)FP qualifying best at Runoffs 2015: 97.5% of SRF's (Kevin Ruck)FP qualifying best at Runoffs 2016: 98.6% of SRF's (John Walker)FP qualifying best at Runoffs 2017: 100.5% of SRF's (Eric Prill)Daytona International Speedway · Runoffs 2015R2015Mid-Ohio Sports Car Course · Runoffs 2016R2016Indianapolis Motor Speedway · Runoffs 2017R2017Sonoma Raceway · Runoffs 2018R2018Virginia International Raceway · Runoffs 2019R2019Road America · Runoffs 2020R2020Indianapolis Motor Speedway · Runoffs 2021R2021Virginia International Raceway · Runoffs 2022R2022Virginia International Raceway · Runoffs 2023R2023Road America · Runoffs 2024R2024Road America · Runoffs 2025R2025Road America · Runoffs 2026R2026
SRFFBF5FPsolid race · dashed qualifying · each class's best lap as a share of SRF's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
EventSRFFBF5FP
Qual best Race best Trap Qual best Race best Trap vs SRF % of SRF Qual best Race best Trap vs SRF % of SRF Qual best Race best Trap vs SRF % of SRF 
Road America Runoffs 20262026-09-282:33.275Stephen Simonds · fastest of 26 · top 5 within 1.0s+0.880s (+0.58%)2:33.240David Strittmatter · fastest of 25 · top 5 within 1.7s-1.031s (-0.67%)132.4David Strittmatter±0.0 mph (±0.0%)
37 rule changes (SRF: 3, FP: 34)10 weight · 9 engine · 7 induction · 2 cars added · 2 suspension & brakes · 1 tyres & wheels · 4 wording · 2 othershowhide
  • SRF GCR Rain/Brake Light Correction #40579suspension & brakes
  • FP Mini Cooper Compression Ratio #40517engine
  • FP 1996-2000 Honda Civic (CX, DX, VP, LX) with Engine Code D16Y7 #40322engine
  • FP 1275 Midget/Sprit Alternate intake manifold E/O #40370induction
  • FP HP Honda Civic (92-95) #40464weight -70 lbs
  • FP Miata track width - errors and omissions #39976wording
  • FP GCR Spec Line Correction #39977induction
  • FP CGR Spec Line Weight Correction #39978weight
  • FP Triumph GT6 Spec Change. #40098induction
  • FP Request to Classify BMW E21 320i #40110cars added
  • FP BMW 318is 84-85 engine displacement correction #40116engine
  • FP Correct Valve Sizes on FP Fiat x19 1300 and 1500 #39850engine
  • FP Dual Carburetor Adjustments #39851induction
  • SRF SRF3 Spark Plugs #39899other
  • FP Request Toyota 5E Series Engines #38208engine
  • FP Request for Toyota 4E Series Engines #38209engine
  • FP Dual Carbs for the Fiat X1/9 #39593induction
  • FP TR2 Notes E&O #39180weight
  • FP Balance of Power #39187weight +50 lbs
  • FP Competition Adjustment Request #39259weight -80 lbs
  • FP Factory Roll Bar Removal on VW Convertible #39268wording
  • FP FP Parity Request #39325weight +50 lbs
  • FP Adjust former-GTL Honda's with B/D-Series Engines #39374engine
  • FP Please Lower Weight of 280Z #38871weight -160 lbs
  • FP Miata Weight Adjustment Follow Up #38949weight -25 lbs
  • FP Weight Break for 1098 Midget / Sprite #38970weight -80 lbs
  • FP HP Volvo 142 spec omission #38994engine
  • FP HP Mini DOHC 1.6 #38996engine
  • FP 83-88 FP Scirocco Spec Line Creation #38997cars added
  • FP Add to Rabbit description #39019wording
  • FP Clean-up 9.1.5.E.7e #39025suspension & brakes
  • FP Add TB size to Ford Mustang (94-98) Spec Line #39130induction
  • FP Correct Existing VW Scirocco Spec Line #39140weight
  • FP HP Plymouth Arrow spec omission #38995wording
  • FP Add Wheel Diameter to Appendix G #39008tyres & wheels
  • FP Add TB ID tolerance to general Prod rules #39009induction
  • SRF Add HD Oil Cooler #38979other
Road America Runoffs 20252025-09-292:32.395David Strittmatter · fastest of 20 · top 5 within 2.9s+0.068s (+0.04%)2:34.271Chris Bovis · fastest of 19 · top 5 within 1.8s+1.025s (+0.67%)132.4David Strittmatter-1.1 mph (-0.8%)
19 rule changes (SRF: 2, FP: 17)7 weight · 4 induction · 2 cars added · 1 engine · 5 othershowhide
  • FP BMW Z4 update #38490induction
  • FP EP Fiat 124 Spider Competition Adjustment Request #38498weight -50 lbs
  • FP Base Weight Adjustment for H-Production X1/9 Spec Lines #38255weight -50 lbs
  • FP Request for Classification of Chevrolet Spark #37755cars added
  • FP Request to Lower Ford Festiva Minimum Weight to 1600 LBS #37939weight -100 lbs
  • SRF Driver Safety & Comfort #37966other
  • SRF Update SADEV transmission specs #37992other
  • FP Request Competition Adjustment to BMW Z3 2.5L #37120induction
  • FP FP Class Adjustments #37458weight
  • FP Interpretation of Production Rules on Mirrors #37235other
  • FP Weight Reduction for Honda S2000 #37466weight
  • FP Mazda 1999 Miata 1.8L #37488weight -50 lbs
  • FP Errors & Omissions #37648cars added
  • FP GTL/FP consolidation 2025 Rules #37659induction
  • FP Effective date for Jan 2025 GCR updates #37654induction
  • FP Request to Reduce Weight of BMW 325i/is E30 (84-91) Spec Line #37119weight -50 lbs
  • FP Fix Error in Spridget Spec Line #37437engine
  • FP Create ruleset that allows GTL cars to run in FP #37485other
  • FP 1275 HP Spridget Level 2 Only #36518other
Road America Runoffs 20242024-10-012:32.327Cliff Ira · fastest of 26 · top 5 within 2.1s+0.913s (+0.60%)2:33.246Kevin Ruck · fastest of 24 · top 5 within 1.4s-0.787s (-0.51%)133.5David Strittmatter+0.3 mph (+0.2%)
31 rule changes (SRF: 10, FP: 21)10 weight · 3 induction · 3 suspension & brakes · 3 tyres & wheels · 2 cars added · 2 engine · 4 wording · 4 othershowhide
  • FP Errors/emissions Honda Civic/CRX #36700wording
  • SRF Update SRF3 Air Filter Rule #36681other
  • SRF Update SRF Brake Rotor Thickness #36687suspension & brakes
  • SRF Hoosier Tire Decal Placement #36739tyres & wheels
  • SRF Protest Fee Clarification #36540wording
  • SRF Update to Letter 36619 with new Hoosier Contingency Decal Info #36624tyres & wheels
  • FP Errant entry in HP production line item #36231other
  • SRF Update Rain Tire Rule and Hoosier Decal Placement #36436tyres & wheels
  • FP NIssan 300ZX Z31 to EP #35830cars added
  • FP RX7 1993 and Up Request In EP Spec Lines, classify #36031cars added
  • FP Clean-up Multiple EP RX-8 Spec Lines In EP #36156wording
  • FP Request to Replace CRX Plastic Panels #35876wording
  • FP FP data and parity #35896induction
  • FP GCR Correction - Redundant HP Spec Lines #35623engine
  • FP Update FP Protege (01-03) Model Info #35715other
  • FP Update 1988-1991 Civic to Match 1988-1991 CRX #35399weight
  • FP FP data #35060weight +25 lbs
  • FP Request to Review Z3 2.5 Spec Line #35073weight +50 lbs
  • FP Corrections to Honda Spec Lines in FP #35250induction
  • FP Miata Alternate Head #35253weight -50 lbs
  • FP Triumph GT6 Adjustments #35255weight
  • FP Honda S2000 throttle body #35272induction
  • FP Correction within Triumph TR8 Spec Line #35315engine
  • FP Correction to EP 924S/944 Spec Line #35317weight
  • SRF Update SRF Rain / Brake Rule #34706suspension & brakes
  • SRF Update SRF Brake Light Rule v1 #34853suspension & brakes
  • SRF SRF / SRF3 Rule Updates #35268weight
  • FP Porsche 944/924S Rule Change Request #35002weight
  • FP FP and HP Toyota Corolla #35030weight -43 lbs
  • FP Triumph GT6 Adjustments #35054weight -30 lbs
  • SRF SRF Radiator Rule Update #34805other
Virginia International Raceway Runoffs 20232023-09-232:08.248Cliff Ira · fastest of 21 · top 5 within 1.0s+2.031s (+1.61%)2:07.787Cliff Ira · fastest of 20 · top 5 within 0.8s-9.854s (-7.16%)133.7Cliff Ira+1.1 mph (+0.9%)
9 rule changes (SRF: 3, FP: 6)2 cars added · 2 induction · 2 tyres & wheels · 1 suspension & brakes · 2 othershowhide
  • FP Correct Intake Valve Size on 1500cc Midget/Spitfire #34419induction
  • FP ITC to FP? #34286other
  • FP Request to Classify Sonic and Fiesta in HP #34264cars added
  • SRF Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheels
  • FP Classification Request for 1978 Toyota Celica #34097cars added
  • SRF Update SRF Front W2 Rain Tire Part Number #34118tyres & wheels
  • SRF Update SRF Brake Rule #33469suspension & brakes
  • FP Request to Add Mazda Protege P5 to FP #33664other
  • FP Review Limited Prep Port Matching Rules #33600induction
Virginia International Raceway Runoffs 20222022-09-241:57.689James Weida · fastest of 11 · top 5 within 3.9s+0.328s (+0.28%)2:21.862Sven de Vries · fastest of 10 · top 5 within 14.3s+24.290s (+20.66%)142.9Calvin Stewart+0.1 mph (+0.1%)2:06.217Eric Prill · fastest of 18 · top 5 within 1.5s-1.219s (-0.96%)2:17.641Mason Workman · fastest of 15 · top 5 within 3.2s+9.565s (+7.47%)132.5Cliff Ira+1.2 mph (+0.9%)
34 rule changes (SRF: 3, F5: 6, FP: 25)11 induction · 6 engine · 4 cars added · 4 weight · 3 tyres & wheels · 1 suspension & brakes · 1 wording · 4 othershowhide
  • F5 Intake Boots Correction #33028induction
  • FP Request to classify VW New Beetle 2.5L in EP #32725cars added
  • FP Request Rotary Injection on Dual Y manifold #32775engine
  • FP Request for Corrado Stroke & Displacement Correction #32985engine
  • F5 Ensure availability of ECU for Rotax engines #32695engine
  • F5 Clarify stepped exhaust header references #32743engine
  • F5 593 carb boot availability and oil pump clarification #32527induction
  • FP Subaru BRZ Model Years #32500other
  • SRF SRF Tire Rule Update #32614tyres & wheels
  • SRF Brake, seal, and air filter clarifications #32670suspension & brakes
  • FP Weight Adjustment of Lotus 7 #32213weight +50 lbs
  • FP EP MX-5 Global Cup Car #32218weight
  • FP Please Class BMW 128i in EP #32370cars added
  • FP Inconsistency in Body Work Descriptions #32396other
  • FP Request to classify the 1999-2000 Mazda Protege in FP #32398cars added
  • FP Mazda RX8 with 13b Rotary #32170induction
  • FP Request Idle control valve clarification #32178engine
  • FP Correct FP BMW 325e/es Displacement #32394engine
  • F5 E&O class name #32194other
  • FP EP Adjustments #31858induction
  • FP 1999 3.8L Ford Mustang to EP? #31635weight
  • FP Improved Touring Tires #32064tyres & wheels
  • FP VW Golf Jetta 2.0L intake and exhaust size correction. #32173induction
  • FP Throttle Body and Idle Air #31800induction
  • F5 Data Box Mounting Plate #31638other
  • FP Porsche 968 Engine Questions #31478induction
  • FP PCS E. 2. n. 4. Add Axle Shaft to Allow FWD the Same Freedom #31592tyres & wheels
  • FP BMW Z3 2.5L Spec Line #31724induction
  • FP FP Del Sol VTEC #31859induction
  • FP Standardize Level 2 Classifications in FP #31868induction
  • FP 944S2 Restrictor #31396induction
  • FP Classing Clarification for 1986 Toyota Corolla FX16 #31527cars added
  • SRF Three Updates to SRF Rules #31523weight
  • FP E&O; MR2 Track #31120wording
Indianapolis Motor Speedway Runoffs 20212021-09-251:42.619Ryan Mayfield · fastest of 22 · top 5 within 1.6s-0.517s (-0.50%)1:43.140Sven de Vries · fastest of 20 · top 5 within 1.7s+0.280s (+0.27%)144.4James Weida1:51.082Craig Chima · fastest of 39 · top 5 within 1.2s-1.009s (-0.90%)1:59.933Cliff Ira · fastest of 33 · top 5 within 5.4s+6.926s (+6.13%)131.8Cliff Ira
30 rule changes (SRF: 6, F5: 3, FP: 21)8 weight · 7 cars added · 6 engine · 3 suspension & brakes · 2 tyres & wheels · 1 induction · 1 wording · 2 othershowhide
  • F5 Clarify allowable assisted shifting systems #30871wording
  • F5 Request to correct terminology #30976tyres & wheels
  • FP Request to Allow F22c Engine for 2000-2003 Honda S2000 #30548engine
  • FP Request a review of the S14 240SX in EP. #30873weight -200 lbs
  • SRF SRF Wet Tires #30849tyres & wheels
  • SRF SADEV-SRF3 Transmission #30926other
  • SRF SRF Update Maintenance, Repairs and Seals #30961engine
  • FP Lotus/Caterham 7 America Request #30392engine
  • FP Request to classify ITC Plymouth Arrow #30588cars added
  • FP Reclassification of the 1984/85 BMW 318i from FP to HP #30661cars added
  • FP Fiat x1/9 Competition Adjustments #30711weight -50 lbs
  • FP Reclassify Daimler SP 250 #30721cars added
  • F5 Request to Allow Rotax 593 HO Engine #30712engine
  • FP Move Porsche 924 in Level 1 Prep From EP to FP #30135cars added
  • FP Clarify Application of Percentage Based Weight Penalties #30669weight
  • SRF SRF3 Alternator Pulley #30684weight
  • FP Change Classification of 84-87 Mazda 626 from FP to HP #30350cars added
  • FP Fiat X1/9 brake rotors #30423suspension & brakes
  • FP Please Classify Mazda3 in FP #30165cars added
  • FP Golf MkIII Valve Size Request #30268engine
  • SRF Mandatory identification: #30223engine
  • FP Alternate Front Brake Rotors and Calipers for EP AH 3000 #29893suspension & brakes
  • FP Request VW weight break #29963weight -50 lbs
  • FP Mk2 VW Consistency and Cleanup of FP and HP Spec Lines #29195weight -50 lbs
  • FP Correct Wording for Level 1 and Level 2 Induction Systems #29406induction
  • FP Weight Reduction for Datsun Roadster #29409weight -75 lbs
  • FP EP TR8 Adjustment #29512weight -100 lbs
  • FP Request to Classify 1996-2000 Honda Civic EX #29515cars added
  • FP FAJS Carburetor #29576other
  • SRF SRF Shocks, Springs and Ride Height. #29688suspension & brakes
Road America Runoffs 20202020-10-022:20.954Calvin Stewart · fastest of 16 · top 5 within 1.8s2:21.391James Weida · fastest of 14 · top 5 within 1.5s143.2Aaron Ellis2:31.414Ethan Shippert · fastest of 23 · top 5 within 2.2s2:34.033Kevin Ruck · fastest of 21 · top 5 within 2.3s133.2Sam Henry
30 rule changes (SRF: 5, F5: 6, FP: 19)6 engine · 5 cars added · 5 induction · 4 weight · 2 suspension & brakes · 2 tyres & wheels · 2 wording · 4 othershowhide
  • F5 Request to Update Suzuki Engine Years for F500 #29453engine
  • FP 84-87 Toyota Corolla HP Wheel Diameter Allowance Proposal E&O #29458tyres & wheels
  • FP EP BMW Z3 Rule Clarification #28998engine
  • F5 Request for Cockpit Adjustment of External Jetting Devices #28359other
  • F5 Two Stroke Motors (reply to #28359 WDYT) #28816engine
  • F5 Re letter requesting driver adjustable carb mixture #28840other
  • F5 #28359 WDYT Request for Cockpit Adjustment #28875other
  • FP Request to Classify Porsche 911 2.0L #28456cars added
  • FP Request to change to Carburetor Spec Line 84-87 Mazda 626 #28926induction
  • FP BMW Cylinder Head Casting and Part Numbers #28708engine
  • FP Correct Scirocco Spec line E&O #28892weight
  • FP Request to Classify 1990-1994 Mazda Protege #28381cars added
  • FP Error in Mini Cooper Spec Line #28713wording
  • SRF SRF Bump Stop Correction #27019suspension & brakes
  • FP Caterham 7 Spec Line #28498engine
  • FP Request to classify SOHC 1989-90 240SX in F prod L2 #28553cars added
  • FP VW Weight and Valve Size Request #27886weight
  • FP Request to allow 40 DCOE carb for the Datsun 510 #28195induction
  • FP Request to classify Porsche 914 2L in LPrep FProd #28231cars added
  • FP Request Ford Fiesta Weight Adjustment #28336weight
  • FP Request for Help for Datsun 1200 #27934induction
  • F5 Change 600cc restrictor size #27883induction
  • FP Request to List Mazda Miata Throttle Body Size #27907induction
  • FP Request to Classify 2001-2003 Mazda Protege ES in FP #27922cars added
  • SRF SRF Rain / Brake Rule - BoD approved as follows #34958suspension & brakes
  • FP Request to Correct Track of 1988-91 Honda Civic #27487wording
  • FP Re-organize Prep2 Cylinder Head Rules for Clarity & Consistency #27661engine
  • SRF SRF Tire Warmer Rule #27622tyres & wheels
  • SRF SRF / SRF3 Nose Weight Reduction #27706weight
  • SRF SRF / SRF3 Majors & Regional Class Updates #27723other
Virginia International Raceway Runoffs 20192019-10-051:54.469Pete Frost · only car1:57.688Pete Frost · only car145.9Pete Frost1:57.361Wiley Mcmahan · fastest of 15 · top 5 within 3.8s1:57.572Wiley Mcmahan · fastest of 15 · top 5 within 4.0s142.8Eric McRee2:07.436Eric Prill · fastest of 19 · top 5 within 0.6s2:08.076Eric Prill · fastest of 18 · top 5 within 0.8s131.4Ken Kannard
11 rule changes (SRF: 1, F5: 1, FP: 9)2 induction · 2 weight · 1 cars added · 1 suspension & brakes · 1 tyres & wheels · 1 wording · 3 othershowhide
  • F5 Request for Weight Increase for Motorcycle Powered Cars #27214weight +25 lbs
  • FP Request bodywork for Austin Healey Bugeye Sprite MK1 #27106other
  • FP Request to classify the GMX5 2019 #27263cars added
  • FP level one susp. component rule #27270suspension & brakes
  • FP Clarification of Carb Rules - Prep 1 #27300induction
  • FP Clarification of Carb Rules - Prep 2 #27301induction
  • FP Request Miata Eligibility - 2003 #27121other
  • SRF SRF Dash Windscreen Kit #27028other
  • FP Rollcenter Correction Clarification #25873tyres & wheels
  • FP Hardtops #26476wording
  • FP Request Classification of Dodge Daytona in F Production #26259weight -150 lbs
Sonoma Raceway Runoffs 20182018-10-101:28.612J R Osborne · fastest of 7 · top 5 within 3.3s1:31.189J R Osborne · fastest of 7 · top 5 within 3.7s140.5J R Osborne1:41.807Jeff Jorgenson · fastest of 5 · top 5 within 6.6s1:42.491David Lapham · fastest of 5 · top 5 within 9.5s113.3David Lapham1:47.588Joe Huffaker · fastest of 15 · top 5 within 3.0s1:48.481Joe Huffaker · fastest of 14 · top 5 within 2.2s109.1Joe Huffaker
No rule changes on record between these events
Indianapolis Motor Speedway Runoffs 20172017-09-251:51.573Thomas Kirchman · fastest of 50 · top 5 within 2.8s1:53.769Todd Harris · fastest of 45 · top 5 within 0.2s1:33.746Gary Hickman · fastest of 18 · top 5 within 3.3s1:33.702Alex Mayer · fastest of 17 · top 5 within 3.0s-20.067squal -17.827s82.4%qual 84.0%1:43.136Wiley Clinton McMahan · fastest of 38 · top 5 within 1.4s1:42.860Wiley Clinton McMahan · fastest of 37 · top 5 within 1.6s-10.909squal -8.437s90.4%qual 92.4%1:52.091Eric Prill · fastest of 42 · top 5 within 1.2s1:53.007Eric Prill · fastest of 40 · top 5 within 0.7s-0.762squal +0.518s99.3%qual 100.5%
No rule changes on record between these events
Mid-Ohio Sports Car Course Runoffs 20162016-09-191:37.344Mike Miserendino · fastest of 27 · top 5 within 0.8s1:37.621Todd Harris · fastest of 27 · top 5 within 0.6s1:19.886Alex Mayer · fastest of 10 · top 5 within 1.5s1:21.015Jeremy Hill · fastest of 10 · top 5 within 1.2s-16.606squal -17.458s83.0%qual 82.1%1:28.528Calvin Stewart · fastest of 14 · top 5 within 3.9s1:29.853Steven Thompson · fastest of 12 · top 5 within 4.5s-7.768squal -8.816s92.0%qual 90.9%1:35.938John Walker · fastest of 33 · top 5 within 0.4s1:36.399John Walker · fastest of 27 · top 5 within 0.3s-1.222squal -1.406s98.7%qual 98.6%
No rule changes on record between these events
Daytona International Speedway Runoffs 20152015-09-212:14.306Cliff White · fastest of 39 · top 5 within 1.2s2:16.700Cliff White · fastest of 38 · top 5 within 0.5s1:50.711J R Osborne · fastest of 20 · top 5 within 1.1s1:51.616J R Osborne · fastest of 19 · top 5 within 2.1s-25.084squal -23.595s81.7%qual 82.4%2:01.824W. Clint McMahan · fastest of 16 · top 5 within 3.0s2:03.298Matthew Strand · fastest of 15 · top 5 within 4.9s-13.402squal -12.482s90.2%qual 90.7%2:11.009Kevin Ruck · fastest of 20 · top 5 within 1.6s2:12.419Kevin Ruck · fastest of 18 · top 5 within 1.1s-4.281squal -3.297s96.9%qual 97.5%

By track

TrackEvents Typical % of SRF Best Latest 
Road America40 of 4 with SRF
Virginia International Raceway30 of 3 with SRF
Indianapolis Motor Speedway2100.0%1 of 2 with SRF100.0%Runoffs 2017100.0%Runoffs 2017
Daytona International Speedway1100.0%100.0%Runoffs 2015100.0%Runoffs 2015
Mid-Ohio Sports Car Course1100.0%100.0%Runoffs 2016100.0%Runoffs 2016
Sonoma Raceway10 of 1 with SRF
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 SRF'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.