BoP Labbeta

BoP Lab / Classes / SRF

SRF vs FB vs F5 vs AS 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)
vsAS×B-SpecEPvsF5×FAvsFB×FCFE2FFFPFVFXGT1GT2GTXHPPP2SMSMXSRF×SRF3STLSTUT1T2T3T4Show 48 inactive classes
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 · AS 89.9% of SRF Andy McDermid, Daytona International Speedway Runoffs 2015 race

1:402:002:206 rule changes between Runoffs 2018 and Runoffs 20196 ▾27 rule changes between Runoffs 2019 and Runoffs 202027 ▾23 rule changes between Runoffs 2020 and Runoffs 202123 ▾18 rule changes between Runoffs 2021 and Runoffs 202218 ▾7 rule changes between Runoffs 2022 and Runoffs 20237 ▾21 rule changes between Runoffs 2023 and Runoffs 202421 ▾13 rule changes between Runoffs 2024 and Runoffs 202513 ▾16 rule changes between Runoffs 2025 and Runoffs 202616 ▾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)Off the chart: 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)AS race best at Runoffs 2015: 2:02.922 (Andy McDermid)AS race best at Runoffs 2016: 1:33.424 (Edward Hosni)AS race best at Runoffs 2017: 1:51.507 (Bryan Long)AS race best at Runoffs 2018: 1:50.345 (John Heinricy)AS race best at Runoffs 2019: 2:03.900 (James Jost)AS race best at Runoffs 2020: 2:27.668 (Gregory Eaton)AS race best at Runoffs 2021: 1:50.606 (Gregory Eaton)AS race best at Runoffs 2022: 2:04.578 (Gregory Eaton)AS race best at Runoffs 2023: 2:04.120 (Gregory Eaton)AS race best at Runoffs 2024: 2:26.429 (Gregory Eaton)AS race best at Runoffs 2025: 2:29.232 (Gregory Eaton)AS race best at Runoffs 2026: 2:28.471 (Andrew McDermid)AS qualifying best at Runoffs 2015: 2:01.746 (Tom Sloe)AS qualifying best at Runoffs 2016: 1:30.651 (Tom Sloe)AS qualifying best at Runoffs 2017: 1:45.220 (James Jost)AS qualifying best at Runoffs 2018: 1:47.782 (Andrew McDermid)AS qualifying best at Runoffs 2019: 2:02.938 (Gregory Eaton)AS qualifying best at Runoffs 2020: 2:27.045 (Gregory Eaton)AS qualifying best at Runoffs 2021: 1:50.427 (Drew Cattell)AS qualifying best at Runoffs 2022: 2:02.162 (Kurt Rezzetano)AS qualifying best at Runoffs 2023: 2:03.082 (Daniel Richardson)AS qualifying best at Runoffs 2024: 2:26.578 (Gregory Eaton)AS qualifying best at Runoffs 2025: 2:26.792 (Andrew McDermid)AS qualifying best at Runoffs 2026: 2:26.911 (Andrew McDermid)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
SRFFBF5ASsolid race · dashed qualifying · slower is lower
80%85%90%95%100%6 rule changes between Runoffs 2018 and Runoffs 20196 ▾27 rule changes between Runoffs 2019 and Runoffs 202027 ▾23 rule changes between Runoffs 2020 and Runoffs 202123 ▾18 rule changes between Runoffs 2021 and Runoffs 202218 ▾7 rule changes between Runoffs 2022 and Runoffs 20237 ▾21 rule changes between Runoffs 2023 and Runoffs 202421 ▾13 rule changes between Runoffs 2024 and Runoffs 202513 ▾16 rule changes between Runoffs 2025 and Runoffs 202616 ▾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)AS race best at Runoffs 2015: 89.9% of SRF's (Andy McDermid)AS race best at Runoffs 2016: 95.7% of SRF's (Edward Hosni)AS race best at Runoffs 2017: 98.0% of SRF's (Bryan Long)AS qualifying best at Runoffs 2015: 90.6% of SRF's (Tom Sloe)AS qualifying best at Runoffs 2016: 93.1% of SRF's (Tom Sloe)AS qualifying best at Runoffs 2017: 94.3% of SRF's (James Jost)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
SRFFBF5ASsolid 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
EventSRFFBF5AS
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 20262026-09-282:26.911Andrew McDermid · fastest of 8 · top 5 within 3.4s+0.119s (+0.08%)2:28.471Andrew McDermid · fastest of 8 · top 5 within 2.4s-0.761s (-0.51%)151.0Andrew McDermid-0.6 mph (-0.4%)
16 rule changes (SRF: 3, AS: 13)5 weight · 3 engine · 2 tyres & wheels · 1 induction · 1 removed · 1 suspension & brakes · 3 othershowhide
  • AS 2016+ Camaro Spec Line Full Prep #39646tyres & wheels
  • AS Consideration of Pirelli P Zero Trofeo Track for AS Competition #40495tyres & wheels
  • SRF GCR Rain/Brake Light Correction #40579suspension & brakes
  • AS Change in 9.1.6.D.4.d.5 in Suspension Mounting Points #40094other
  • AS Re-Add 4.6L 4v 96-04 Mustang Cobra #40239weight
  • AS Errors and Omissions #40532weight
  • AS Clarification for LM7 Holley Carburetor #40167engine
  • AS Header Information Update for EFI Engine Build Sheets #39886engine
  • AS Errors and Omissions #39933weight
  • AS Re-Organization of AS Spec lines for 2026 #39887removed
  • SRF SRF3 Spark Plugs #39899other
  • AS Edelbrock manifold (& timing kit) to Chevy LS Spec Lines Request #39055weight
  • AS Restrictor Plate Change for Gen 2 Ford Coyote Engine #39501induction
  • AS 1994 Mustang Spec Line Request #39104engine
  • AS Cadillac CTS-V BOP Weight Change #38640weight -50 lbs
  • SRF Add HD Oil Cooler #38979other
Road America Runoffs 20252025-09-292:26.792Andrew McDermid · fastest of 11 · top 5 within 3.9s+0.214s (+0.15%)2:29.232Gregory Eaton · fastest of 10 · top 5 within 4.0s+2.803s (+1.91%)151.5Andrew McDermid+1.9 mph (+1.3%)
13 rule changes (SRF: 2, AS: 11)5 engine · 3 weight · 2 induction · 3 othershowhide
  • AS RE: Previous Letter 37695 Update #38245weight -75 lbs
  • AS Errors and Omissions #38234engine
  • AS Errors and Omission #38055induction
  • AS Request to Add LS1/LS6 Intakes for 5.3L Truck Engine EnO #38197engine
  • AS Flotek Head Plunge Cut Inconsistencies #37502other
  • AS Notes clean up #37693weight
  • SRF Driver Safety & Comfort #37966other
  • SRF Update SADEV transmission specs #37992other
  • AS Race memo #37902engine
  • AS Increase Coyote Engine Restrictor to 80mm #36177induction
  • AS Performance Pack for 2015+ Mustang #36867weight
  • AS Gear Ratios #37131engine
  • AS ECU specs for LS engine #37208engine
Road America Runoffs 20242024-10-012:26.578Gregory Eaton · fastest of 18 · top 5 within 2.6s-0.467s (-0.32%)2:26.429Gregory Eaton · fastest of 18 · top 5 within 2.5s-1.239s (-0.84%)149.6Gregory Eaton+0.4 mph (+0.3%)
21 rule changes (SRF: 10, AS: 11)6 cars added · 4 tyres & wheels · 3 suspension & brakes · 1 engine · 1 weight · 1 wording · 5 othershowhide
  • SRF Update SRF3 Air Filter Rule #36681other
  • SRF Update SRF Brake Rotor Thickness #36687suspension & brakes
  • SRF Hoosier Tire Decal Placement #36739tyres & wheels
  • AS Mustang transmission ratios #36662engine
  • SRF Protest Fee Clarification #36540wording
  • SRF Update to Letter 36619 with new Hoosier Contingency Decal Info #36624tyres & wheels
  • SRF Update Rain Tire Rule and Hoosier Decal Placement #36436tyres & wheels
  • AS Request for Classification of 2018-2023 mustang In #35764cars added
  • AS 6th gen Camaro limited prep #35733cars added
  • AS Chevrolet/Pontiac Camaro & Firebird (82-92) 5.7L V8 LS1 Alum BLK #35825cars added
  • AS Full Prep Head #35891other
  • AS Restricted Prep Aftermarket Parts Request #35682other
  • AS Allowance of 11 #35824tyres & wheels
  • AS Request to Classify 1970-1981 Camaro and Firebird in AS #33659cars added
  • AS Fuel Cell 12 #34194other
  • AS Please Classify the 6th Gen Into AS. #35448cars added
  • AS spec lines #35713cars added
  • SRF Update SRF Rain / Brake Rule #34706suspension & brakes
  • SRF Update SRF Brake Light Rule v1 #34853suspension & brakes
  • SRF SRF / SRF3 Rule Updates #35268weight
  • SRF SRF Radiator Rule Update #34805other
Virginia International Raceway Runoffs 20232023-09-232:03.082Daniel Richardson · fastest of 11 · top 5 within 2.2s+0.920s (+0.75%)2:04.120Gregory Eaton · fastest of 9 · top 5 within 3.0s-0.458s (-0.37%)154.6James Jost+3.7 mph (+2.5%)
7 rule changes (SRF: 3, AS: 4)3 tyres & wheels · 2 engine · 2 suspension & brakesshowhide
  • AS Crate Motor Part Numbers #32944engine
  • AS Request wheel size change #33007tyres & wheels
  • AS Alternative Upper Front Control Arms for Dodge Challenger #33352engine
  • AS Front Brake Caliper Adapters for Dodge Challenger #33353suspension & brakes
  • SRF Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheels
  • SRF Update SRF Front W2 Rain Tire Part Number #34118tyres & wheels
  • SRF Update SRF Brake Rule #33469suspension & brakes
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%)2:02.162Kurt Rezzetano · fastest of 13 · top 5 within 2.3s-0.776s (-0.63%)2:04.578Gregory Eaton · fastest of 11 · top 5 within 2.9s+0.678s (+0.55%)150.9James Jost-3.0 mph (-2.0%)
18 rule changes (SRF: 3, F5: 6, AS: 9)3 engine · 3 weight · 2 induction · 2 suspension & brakes · 1 tyres & wheels · 2 wording · 5 othershowhide
  • AS Request to add Hoosier W2 #33031other
  • AS correction of Dodge Challenger specification line #33151wording
  • F5 Intake Boots Correction #33028induction
  • F5 Ensure availability of ECU for Rotax engines #32695engine
  • AS Request CTS-V Spec Line Error Correction #30242weight
  • F5 Clarify stepped exhaust header references #32743engine
  • F5 593 carb boot availability and oil pump clarification #32527induction
  • SRF SRF Tire Rule Update #32614tyres & wheels
  • SRF Brake, seal, and air filter clarifications #32670suspension & brakes
  • F5 E&O class name #32194other
  • AS Proposed Revisions to SCCA GCR 2021 Appendix M, Part 3 #30295other
  • AS specification line consolidation and correction #31846wording
  • AS correction of SMG specification line #31847suspension & brakes
  • AS Alternate cylinder heads for full prep engine builds - Evaluation #31851engine
  • F5 Data Box Mounting Plate #31638other
  • SRF Three Updates to SRF Rules #31523weight
  • AS Request for adjustable Front Upper Control Arms on 4th Gen F-Body #30457other
  • AS Request Pontiac GTO tire size change #30881weight
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 Weida1:50.427Drew Cattell · fastest of 31 · top 5 within 1.9s+5.207s (+4.95%)1:50.606Gregory Eaton · fastest of 28 · top 5 within 1.7s-0.901s (-0.81%)153.8James Jost
23 rule changes (SRF: 6, F5: 3, AS: 14)7 weight · 6 engine · 3 cars added · 2 tyres & wheels · 1 suspension & brakes · 3 wording · 1 othershowhide
  • F5 Clarify allowable assisted shifting systems #30871wording
  • F5 Request to correct terminology #30976tyres & wheels
  • SRF SRF Wet Tires #30849tyres & wheels
  • SRF SADEV-SRF3 Transmission #30926other
  • SRF SRF Update Maintenance, Repairs and Seals #30961engine
  • AS Request CTS-V Spec Line Error Correction #30242weight
  • AS Request to consolidate SN95 Mustang '94-'04 Mustang spec lines #30428cars added
  • AS American Sedan Transmission Rule Change Request #30595weight
  • AS Correction to specifications inadvertently deleted #30691wording
  • AS weight adjustments #30700weight +50 lbs
  • F5 Request to Allow Rotax 593 HO Engine #30712engine
  • SRF SRF3 Alternator Pulley #30684weight
  • AS AS Mustang LP 4.6 3V Classification Transmission Request #29886weight
  • AS Request CF driveshaft on CTS-V for durability improvement #30117engine
  • AS Adjustment to model years of 5th generation RP Camaro #30348engine
  • SRF Mandatory identification: #30223engine
  • AS Request for 2015 -2017 Ford Mustang Spec Line #29514cars added
  • AS Request Trunk lid / Rear Hatch clarification #29591wording
  • AS Common Weight for CTS-V Tire #29759weight
  • AS Correction to specifications inadvertently deleted #30041cars added
  • AS Request Additional Engine Options for Dodge Challenger Spec Line #29543engine
  • AS Rule simplification spec line communization #29824weight
  • 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 Ellis2:27.045Gregory Eaton · fastest of 18 · top 5 within 0.6s2:27.668Gregory Eaton · fastest of 15 · top 5 within 1.5s149.2Gregory Eaton
27 rule changes (SRF: 5, F5: 6, AS: 16)5 engine · 4 suspension & brakes · 3 induction · 3 tyres & wheels · 3 weight · 2 cars added · 1 aero · 6 othershowhide
  • F5 Request to Update Suzuki Engine Years for F500 #29453engine
  • AS Dodge Challenger AS Spec Line Clarification #28698induction
  • AS Dodge Challenger AS Spec Line Clarification #2 #28699aero
  • AS Support for R-Type Specification Tires #27450tyres & wheels
  • AS Spec Tire Request #27519tyres & wheels
  • AS Restrictor Plate Change for RP 2011+ Mustang with Coyote Engine #27675induction
  • AS 2005-2009 Restricted Prep 4.6 3V #27908engine
  • AS Request for 2005-2009 Restricted Prep 4.6 3V Parts #27909engine
  • AS Request for Full Preparation Classification for 2010-2014 Camaro #28030other
  • AS Cylinder Heads #28696engine
  • AS Request for Max Rotor Diameter Change #28748suspension & brakes
  • AS Request increase rotor diameter #28797other
  • 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
  • AS weight adjustments for 2020 season #28785weight -50 lbs
  • SRF SRF Bump Stop Correction #27019suspension & brakes
  • AS Rear Trailing Arms #28007suspension & brakes
  • AS Weight reduction for cars running iron heads #28010weight
  • AS 05-10 Mustang with HR cam classification #28226cars added
  • AS 10-15 Camaro Full Prep classification #28227cars added
  • F5 Change 600cc restrictor size #27883induction
  • SRF SRF Rain / Brake Rule - BoD approved as follows #34958suspension & brakes
  • 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 McRee2:02.938Gregory Eaton · fastest of 17 · top 5 within 0.8s2:03.900James Jost · fastest of 16 · top 5 within 2.1s153.9James Jost
6 rule changes (SRF: 1, F5: 1, AS: 4)2 weight · 1 cars added · 1 suspension & brakes · 2 othershowhide
  • AS Request to add SMG to 9.1.6.B.1 AS Intent #27140other
  • F5 Request for Weight Increase for Motorcycle Powered Cars #27214weight +25 lbs
  • AS Request Ride Height Clarification #26598suspension & brakes
  • SRF SRF Dash Windscreen Kit #27028other
  • AS Request to Revert to 2017 Weights #25885weight
  • AS SMG Mustang eligibility in American sedan #26224cars added
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 Lapham1:47.782Andrew McDermid · fastest of 12 · top 5 within 1.9s1:50.345John Heinricy · fastest of 10 · top 5 within 2.3s105.0Kevin Fandozzi
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%1:45.220James Jost · fastest of 29 · top 5 within 6.7s1:51.507Bryan Long · fastest of 28 · top 5 within 0.9s-2.262squal -6.353s98.0%qual 94.3%
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%1:30.651Tom Sloe · fastest of 22 · top 5 within 3.6s1:33.424Edward Hosni · fastest of 20 · top 5 within 1.0s-4.197squal -6.693s95.7%qual 93.1%
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%2:01.746Tom Sloe · fastest of 22 · top 5 within 2.6s2:02.922Andy McDermid · fastest of 19 · top 5 within 2.2s-13.778squal -12.560s89.9%qual 90.6%

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.