BoP Labbeta

BoP Lab / Classes / SRF

SRF vs FC 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)
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 · FC 84.0% of SRF Nigel Saurino, Mid-Ohio Sports Car Course Runoffs 2016 race

1:201:402:002:203 rule changes between Runoffs 2018 and Runoffs 20193 ▾9 rule changes between Runoffs 2019 and Runoffs 20209 ▾7 rule changes between Runoffs 2020 and Runoffs 20217 ▾8 rule changes between Runoffs 2021 and Runoffs 20228 ▾6 rule changes between Runoffs 2022 and Runoffs 20236 ▾12 rule changes between Runoffs 2023 and Runoffs 202412 ▾4 rule changes between Runoffs 2024 and Runoffs 20254 ▾5 rule changes between Runoffs 2025 and Runoffs 20265 ▾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)FC race best at Runoffs 2015: 1:55.135 (Yufeng Luo)FC race best at Runoffs 2016: 1:22.049 (Nigel Saurino)FC race best at Runoffs 2017: 1:36.890 (Tim Minor)FC race best at Runoffs 2018: 1:34.053 (Mitch Egner)FC race best at Runoffs 2019: 1:52.174 (Robert Allaer)FC race best at Runoffs 2020: 2:13.608 (Robert Allaer)FC race best at Runoffs 2021: 1:36.980 (Simon Sikes)FC race best at Runoffs 2022: 2:07.859 (Nolan Allaer)FC race best at Runoffs 2023: 1:51.169 (Nolan Allaer)FC race best at Runoffs 2024: 2:11.534 (Michael Varacins)FC race best at Runoffs 2025: 2:12.824 (Brandon Dixon)FC race best at Runoffs 2026: 2:11.389 (Brandon Dixon)FC qualifying best at Runoffs 2015: 1:54.477 (Yufeng Luo)FC qualifying best at Runoffs 2016: 1:21.962 (John LaRue)FC qualifying best at Runoffs 2017: 1:36.336 (Austin McCusker)FC qualifying best at Runoffs 2018: 1:32.571 (Timothy de Silva)FC qualifying best at Runoffs 2019: 1:51.200 (Robert Allaer)FC qualifying best at Runoffs 2020: 2:12.644 (Robert Allaer)FC qualifying best at Runoffs 2021: 1:36.787 (Trent Walko)FC qualifying best at Runoffs 2022: 1:49.895 (Nolan Allaer)FC qualifying best at Runoffs 2023: 1:50.281 (Nolan Allaer)FC qualifying best at Runoffs 2024: 2:11.626 (Timothy Minor)FC qualifying best at Runoffs 2025: 2:11.259 (Brandon Dixon)FC qualifying best at Runoffs 2026: 2:10.686 (Brandon Dixon)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
SRFFCsolid race · dashed qualifying · slower is lower
85%90%95%100%3 rule changes between Runoffs 2018 and Runoffs 20193 ▾9 rule changes between Runoffs 2019 and Runoffs 20209 ▾7 rule changes between Runoffs 2020 and Runoffs 20217 ▾8 rule changes between Runoffs 2021 and Runoffs 20228 ▾6 rule changes between Runoffs 2022 and Runoffs 20236 ▾12 rule changes between Runoffs 2023 and Runoffs 202412 ▾4 rule changes between Runoffs 2024 and Runoffs 20254 ▾5 rule changes between Runoffs 2025 and Runoffs 20265 ▾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)FC race best at Runoffs 2015: 84.2% of SRF's (Yufeng Luo)FC race best at Runoffs 2016: 84.0% of SRF's (Nigel Saurino)FC race best at Runoffs 2017: 85.2% of SRF's (Tim Minor)FC qualifying best at Runoffs 2015: 85.2% of SRF's (Yufeng Luo)FC qualifying best at Runoffs 2016: 84.2% of SRF's (John LaRue)FC qualifying best at Runoffs 2017: 86.3% of SRF's (Austin McCusker)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
SRFFCsolid 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
EventSRFFC
Qual best Race best Trap Qual best Race best Trap vs SRF % of SRF 
Road America Runoffs 20262026-09-282:10.686Brandon Dixon · fastest of 10 · top 5 within 4.0s-0.573s (-0.44%)2:11.389Brandon Dixon · fastest of 10 · top 5 within 2.7s-1.435s (-1.08%)143.3Dean Kiriluk-1.8 mph (-1.2%)
5 rule changes (SRF: 3, FC: 2)2 engine · 1 weight · 1 wording · 1 other · SRF rain/brake light part number and GCR section reference corrected for original roll hoop mounting. · SRF3 spark plugs limited to NGK LTR7IX-11 P/N G301041 only; washers and sealing rings prohibited. · FC USF2000 Tube Frame may now use Hewland LD200 4-speed H-pattern as alternative to Hewland JL-200 5-speed sequential. · FC F2000 Metrik ZF2 minimum weight reduced to 1220 lbs. · SRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted.showhide
  • SRF GCR Rain/Brake Light Correction #40579wordingwordingSRF rain/brake light part number and GCR section reference corrected for original roll hoop mounting.
  • SRF SRF3 Spark Plugs #39899engineengineSRF3 spark plugs limited to NGK LTR7IX-11 P/N G301041 only; washers and sealing rings prohibited.
  • FC F2000 MZR Spec Line Clarity/Revision Requested #38927otheraddedFC USF2000 Tube Frame may now use Hewland LD200 4-speed H-pattern as alternative to Hewland JL-200 5-speed sequential.
  • FC Adjust F2000 Metrik ZF2 weight #39612weight -20 lbsfasterweightFC F2000 Metrik ZF2 minimum weight reduced to 1220 lbs.
  • SRF Add HD Oil Cooler #38979engineaddedengineSRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted.
Road America Runoffs 20252025-09-292:11.259Brandon Dixon · fastest of 10 · top 5 within 2.7s-0.367s (-0.28%)2:12.824Brandon Dixon · fastest of 9 · top 5 within 2.3s+1.290s (+0.98%)145.1Brandon Dixon+0.9 mph (+0.6%)
4 rule changes (SRF: 2, FC: 2)1 weight · 2 wording · 1 other · 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. · FC tire rule clarified: four dry and four wet tires for Regionals and Majors, eight each for Runoffs; marking and declaration timing adjusted. · FF and FC sequential gearbox weight penalty reduces from 25 lbs to 10 lbs minimum weight addition.showhide
  • SRF Driver Safety & Comfort #37966otheraddedSRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only.
  • SRF Update SADEV transmission specs #37992wordingwordingSRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward.
  • FC 9.1.1.10.h. FC Tire Rule #36533wordingwordingFC tire rule clarified: four dry and four wet tires for Regionals and Majors, eight each for Runoffs; marking and declaration timing adjusted.
  • FC Change FF/FC Weight with Sequential Gearbox #36651weightfasterweightFF and FC sequential gearbox weight penalty reduces from 25 lbs to 10 lbs minimum weight addition.
Road America Runoffs 20242024-10-012:11.626Timothy Minor · fastest of 10 · top 5 within 1.3s-1.018s (-0.77%)2:11.534Michael Varacins · fastest of 9 · top 5 within 1.8s-2.074s (-1.55%)144.2Michael Varacins+1.8 mph (+1.2%)
12 rule changes (SRF: 10, FC: 2)2 suspension & brakes · 1 cars added · 1 tyres & wheels · 1 weight · 4 wording · 3 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. · FE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure. · SRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement. · 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. · FC F2000 Metrik ZF2 added as spec line car with Brembo 4-piston calipers and vented rotors permitted. · 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. · SRF radiator options expanded: Enterprises P/N 480465 with baffle 480464, 480466, or Automotive 1R698 and CU698 allowed if cross-reference equivalent.showhide
  • SRF Update SRF3 Air Filter Rule #36681wordingremovedSRF3 air filter rule removes K&N RC-9160 option, specifies Weems P/N WM301020 only.
  • SRF Update SRF Brake Rotor Thickness #36687suspension & brakessuspension & brakesSRF Wilwood vented rotor minimum thickness increases to 13.25mm, 0.522 inches.
  • SRF Hoosier Tire Decal Placement #36739wordingwordingSRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front.
  • SRF Protest Fee Clarification #36540wordingwordingFE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure.
  • SRF Update to Letter 36619 with new Hoosier Contingency Decal Info #36624wordingwordingSRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement.
  • SRF Update Rain Tire Rule and Hoosier Decal Placement #36436tyres & wheelstyres & wheelsSRF 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.
  • FC Four Pot Calipers #35481cars addedaddedFC F2000 Metrik ZF2 added as spec line car with Brembo 4-piston calipers and vented rotors permitted.
  • FC Please correct omitted punctuation #34890weight
  • SRF Update SRF Rain / Brake Rule #34706otherotherSRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch.
  • SRF Update SRF Brake Light Rule v1 #34853otherotherSRF 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 SRF / SRF3 Rule Updates #35268suspension & brakessuspension & brakesSRF 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.
  • SRF SRF Radiator Rule Update #34805otheraddedSRF radiator options expanded: Enterprises P/N 480465 with baffle 480464, 480466, or Automotive 1R698 and CU698 allowed if cross-reference equivalent.
Virginia International Raceway Runoffs 20232023-09-231:50.281Nolan Allaer · fastest of 11 · top 5 within 2.3s+0.386s (+0.35%)1:51.169Nolan Allaer · fastest of 11 · top 5 within 2.5s-16.690s (-13.05%)143.5Robert Allaer+2.3 mph (+1.7%)
6 rule changes (SRF: 3, FC: 3)2 tyres & wheels · 1 cars added · 1 engine · 2 wording · FC tire marking rule clarified: four dry and four wet tires for Regional/Major/Super Tour, eight each for Runoffs; undeclared tire penalty removed. · USF2000 Van Diemen with Mazda MZR LF-DE 2.0L added to FC as spec line car; removed from FX. · 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. · 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. · FC/FF PE3-8400 ECU tune-file firmware version changes from V3.04.50 to V3.04.35.showhide
  • FC Review FC Runoffs Tire Marking Rule #34274wordingwordingFC tire marking rule clarified: four dry and four wet tires for Regional/Major/Super Tour, eight each for Runoffs; undeclared tire penalty removed.
  • FC USF2000 Van Diemen with Mazda MZR LF-DE 2.0L in FC #34329cars addedaddedUSF2000 Van Diemen with Mazda MZR LF-DE 2.0L added to FC as spec line car; removed from FX.
  • SRF Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheelstyres & wheelsSRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance.
  • SRF Update SRF Front W2 Rain Tire Part Number #34118tyres & wheelstyres & wheelsSRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13.
  • SRF Update SRF Brake Rule #33469enginefasterengineSRF 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.
  • FC E&O 9.1.1.B.16.j #33634wordingwordingFC/FF PE3-8400 ECU tune-file firmware version changes from V3.04.50 to V3.04.35.
Virginia International Raceway Runoffs 20222022-09-241:49.895Nolan Allaer · fastest of 12 · top 5 within 1.5s-1.305s (-1.17%)2:07.859Nolan Allaer · fastest of 13 · top 5 within 3.8s+15.685s (+13.98%)141.2Tim Minor-0.6 mph (-0.4%)
8 rule changes (SRF: 3, FC: 5)6 wording · 2 other · FC Zetec ECU: Performance Electronics model designation changed from PE-3 to PE3-8400; monitor firmware updated to V3.04.50. · 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. · FC chassis/frame section cleaned up: panels between main tubes must prevent cockpit intrusion; suspension cannot mount to exterior panels; engine/gearbox exempt from load-bearing restrictions. · FC Zetec ECU requirements clarified: Pectel T2 or PE-3 required with specified communications ports and SCCA tune-file/map from official website. · 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… · FC composite anti-intrusion panels of non-uniform thickness limited to eight fasteners per side. · FC tire marking requirements clarified: competitor must ensure tires declared, marked, and logged by Tech before qualifying or race use.showhide
  • FC Add Specification to Performance Electronics ECU for Ford Zetec #32761wordingwordingFC Zetec ECU: Performance Electronics model designation changed from PE-3 to PE3-8400; monitor firmware updated to V3.04.50.
  • SRF SRF Tire Rule Update #32614wordingwordingSRF tire rule wording clarified: tires must be run as delivered.
  • SRF Brake, seal, and air filter clarifications #32670otherfasterSRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified.
  • FC Clean up Chassis/Frame section #31867wordingwordingFC chassis/frame section cleaned up: panels between main tubes must prevent cockpit intrusion; suspension cannot mount to exterior panels; engine/gearbox exempt from load-bearing restrictions.
  • FC Clarify Zetec ECU requirements #31554wordingwordingFC Zetec ECU requirements clarified: Pectel T2 or PE-3 required with specified communications ports and SCCA tune-file/map from official website.
  • SRF Three Updates to SRF Rules #31523otherotherSRF 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…
  • FC Clarify composite anti-intrusion panel language #31426wordingwordingFC composite anti-intrusion panels of non-uniform thickness limited to eight fasteners per side.
  • FC Clarify tire marking requirements #31455wordingwordingFC tire marking requirements clarified: competitor must ensure tires declared, marked, and logged by Tech before qualifying or race use.
Indianapolis Motor Speedway Runoffs 20212021-09-251:36.787Trent Walko · fastest of 31 · top 5 within 1.7s+0.451s (+0.47%)1:36.980Simon Sikes · fastest of 31 · top 5 within 2.0s+0.090s (+0.09%)141.6Tim Minor
7 rule changes (SRF: 6, FC: 1)1 cars added · 1 engine · 1 tyres & wheels · 1 weight · 2 wording · 1 other · 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. · SRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz. · FC Pinto engine loses 10 lbs to 1190; Pinto aluminum head loses 10 lbs to 1190; Zetec loses 10 lbs to 1210. · SRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement. · SRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified.showhide
  • SRF SRF Wet Tires #30849tyres & wheelsaddedtyres & wheelsSRF wet tyres add Hoosier W2 option alongside existing H20 from October 4, 2021.
  • SRF SADEV-SRF3 Transmission #30926cars addedaddedSRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive.
  • SRF SRF Update Maintenance, Repairs and Seals #30961wordingwordingSRF 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.
  • SRF SRF3 Alternator Pulley #30684engineaddedengineSRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz.
  • FC Request for FC Weight Change #30171weightfasterweightFC Pinto engine loses 10 lbs to 1190; Pinto aluminum head loses 10 lbs to 1190; Zetec loses 10 lbs to 1210.
  • SRF Mandatory identification: #30223wordingwordingSRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement.
  • SRF SRF Shocks, Springs and Ride Height. #29688otherotherSRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified.
Road America Runoffs 20202020-10-022:12.644Robert Allaer · fastest of 13 · top 5 within 2.1s2:13.608Robert Allaer · fastest of 11 · top 5 within 1.2s142.4Robert Allaer
9 rule changes (SRF: 5, FC: 4)2 engine · 2 weight · 1 tyres & wheels · 4 wording · FC ECU maps clarified: SCCA Club or 2013 Pro map required, available on SCCA website; 1.340 restrictor reminder. · FC Zetec engine minimum weight increases 20 lbs to 1220 lbs. · SRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020. · SRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024. · FC allows Eagle #CRS5483F3D connecting rods alongside original Ford; crankshaft replacement clarified to original Ford only. · FC allows Mahle #930169439 piston as new option alongside Ford original, Sealed Power #H872cp, United Engine and Machine #SO2763. · 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.showhide
  • FC Urgent: SCCA PE3 map unsuitable #29475wordingwordingFC ECU maps clarified: SCCA Club or 2013 Pro map required, available on SCCA website; 1.340 restrictor reminder.
  • FC Request for weight adjustments to equalize FC competition. #28888weightslowerweightFC Zetec engine minimum weight increases 20 lbs to 1220 lbs.
  • SRF SRF Bump Stop Correction #27019wordingwordingSRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020.
  • SRF SRF Rain / Brake Rule - BoD approved as follows #34958wordingwordingSRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024.
  • FC Request for Better Zetec Connecting Rods #27710engineaddedengineFC allows Eagle #CRS5483F3D connecting rods alongside original Ford; crankshaft replacement clarified to original Ford only.
  • FC Add Alternate Piston #27795engineaddedengineFC allows Mahle #930169439 piston as new option alongside Ford original, Sealed Power #H872cp, United Engine and Machine #SO2763.
  • SRF SRF Tire Warmer Rule #27622tyres & wheelstyres & wheelsSRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers.
  • SRF SRF / SRF3 Nose Weight Reduction #27706weightfasterweightSRF front nose weight minimum reduced from 35 to 32 lbs.
  • SRF SRF / SRF3 Majors & Regional Class Updates #27723wordingwordingSRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points.
Virginia International Raceway Runoffs 20192019-10-051:51.200Robert Allaer · fastest of 10 · top 5 within 3.1s1:52.174Robert Allaer · fastest of 9 · top 5 within 2.7s141.8Robert Allaer
3 rule changes (SRF: 1, FC: 2)1 aero · 2 wording · SRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102. · FC Wiseco piston and Crower rod part numbers updated; minimum weight unchanged at 976 grams. · FC Wiseco piston and connecting rod minimum weight corrected to 976 grams.showhide
  • SRF SRF Dash Windscreen Kit #27028aeroaddedaeroSRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102.
  • FC E&O Wiseco piston and Crower connecting rod #26659wordingwordingFC Wiseco piston and Crower rod part numbers updated; minimum weight unchanged at 976 grams.
  • FC Correct Wiseco piston and connecting rod #25809wordingwordingFC Wiseco piston and connecting rod minimum weight corrected to 976 grams.
Sonoma Raceway Runoffs 20182018-10-101:32.571Timothy de Silva · fastest of 16 · top 5 within 1.8s1:34.053Mitch Egner · fastest of 12 · top 5 within 1.6s133.1Robert Armington
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 0.2s1:36.336Austin McCusker · fastest of 14 · top 5 within 2.3s1:36.890Tim Minor · fastest of 14 · top 5 within 3.8s-16.879squal -15.237s85.2%qual 86.3%
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 0.6s1:21.962John LaRue · fastest of 7 · top 5 within 2.6s1:22.049Nigel Saurino · fastest of 7 · top 5 within 3.0s-15.572squal -15.382s84.0%qual 84.2%
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 0.5s1:54.477Yufeng Luo · fastest of 11 · top 5 within 2.5s1:55.135Yufeng Luo · fastest of 10 · top 5 within 2.1s-21.565squal -19.829s84.2%qual 85.2%

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.