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BoP Lab / Classes / FC

FC vs FB vs F5 vs FM pace at every track

Lap times across years say as much about the weather as the class. % of FC is each class's best lap as a share of FC'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: FC 100.0% of FC Yufeng Luo, Daytona International Speedway Runoffs 2015 race · FB 95.7% of FC J R Osborne, Sonoma Raceway Runoffs 2018 qualifying · F5 104.8% of FC Wiley Mcmahan, Virginia International Raceway Runoffs 2019 race · FM 102.5% of FC Joseph Burton-Harris, Daytona International Speedway Runoffs 2015 race

1:201:402:002:203 rule changes between Runoffs 2018 and Runoffs 20193 ▾10 rule changes between Runoffs 2019 and Runoffs 202010 ▾4 rule changes between Runoffs 2020 and Runoffs 20214 ▾11 rule changes between Runoffs 2021 and Runoffs 202211 ▾3 rule changes between Runoffs 2022 and Runoffs 20233 ▾2 rule changes between Runoffs 2023 and Runoffs 20242 ▾2 rule changes between Runoffs 2024 and Runoffs 20252 ▾2 rule changes between Runoffs 2025 and Runoffs 20262 ▾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)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)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)FM race best at Runoffs 2015: 1:58.029 (Joseph Burton-Harris)FM race best at Runoffs 2016: 1:27.922 (Jacob Loomis)FM race best at Runoffs 2017: 1:41.146 (Jarret Voorhies)FM race best at Runoffs 2018: 1:37.909 (Bryce Cornet)FM race best at Runoffs 2019: 2:15.816 (Bryce Cornet)FM qualifying best at Runoffs 2015: 1:57.804 (Joseph Burton-Harris)FM qualifying best at Runoffs 2016: 1:26.043 (Jacob Loomis)FM qualifying best at Runoffs 2017: 1:41.231 (Jarret Voorhies)FM qualifying best at Runoffs 2018: 1:37.598 (Bryce Cornet)FM qualifying best at Runoffs 2019: 1:55.124 (Bryce Cornet)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
FCFBF5FMsolid race · dashed qualifying · slower is lower
100%105%110%3 rule changes between Runoffs 2018 and Runoffs 20193 ▾10 rule changes between Runoffs 2019 and Runoffs 202010 ▾4 rule changes between Runoffs 2020 and Runoffs 20214 ▾11 rule changes between Runoffs 2021 and Runoffs 202211 ▾3 rule changes between Runoffs 2022 and Runoffs 20233 ▾2 rule changes between Runoffs 2023 and Runoffs 20242 ▾2 rule changes between Runoffs 2024 and Runoffs 20252 ▾2 rule changes between Runoffs 2025 and Runoffs 20262 ▾FC race best at Runoffs 2015: 100.0% of FC's (Yufeng Luo)FC race best at Runoffs 2016: 100.0% of FC's (Nigel Saurino)FC race best at Runoffs 2017: 100.0% of FC's (Tim Minor)FC race best at Runoffs 2018: 100.0% of FC's (Mitch Egner)FC race best at Runoffs 2019: 100.0% of FC's (Robert Allaer)FC race best at Runoffs 2020: 100.0% of FC's (Robert Allaer)FC race best at Runoffs 2021: 100.0% of FC's (Simon Sikes)FC race best at Runoffs 2022: 100.0% of FC's (Nolan Allaer)FC race best at Runoffs 2023: 100.0% of FC's (Nolan Allaer)FC race best at Runoffs 2024: 100.0% of FC's (Michael Varacins)FC race best at Runoffs 2025: 100.0% of FC's (Brandon Dixon)FC race best at Runoffs 2026: 100.0% of FC's (Brandon Dixon)FC qualifying best at Runoffs 2015: 100.0% of FC's (Yufeng Luo)FC qualifying best at Runoffs 2016: 100.0% of FC's (John LaRue)FC qualifying best at Runoffs 2017: 100.0% of FC's (Austin McCusker)FC qualifying best at Runoffs 2018: 100.0% of FC's (Timothy de Silva)FC qualifying best at Runoffs 2019: 100.0% of FC's (Robert Allaer)FC qualifying best at Runoffs 2020: 100.0% of FC's (Robert Allaer)FC qualifying best at Runoffs 2021: 100.0% of FC's (Trent Walko)FC qualifying best at Runoffs 2022: 100.0% of FC's (Nolan Allaer)FC qualifying best at Runoffs 2023: 100.0% of FC's (Nolan Allaer)FC qualifying best at Runoffs 2024: 100.0% of FC's (Timothy Minor)FC qualifying best at Runoffs 2025: 100.0% of FC's (Brandon Dixon)FC qualifying best at Runoffs 2026: 100.0% of FC's (Brandon Dixon)FB race best at Runoffs 2015: 96.9% of FC's (J R Osborne)FB race best at Runoffs 2016: 98.7% of FC's (Jeremy Hill)FB race best at Runoffs 2017: 96.7% of FC's (Alex Mayer)FB race best at Runoffs 2018: 97.0% of FC's (J R Osborne)FB race best at Runoffs 2019: 104.9% of FC's (Pete Frost)FB qualifying best at Runoffs 2015: 96.7% of FC's (J R Osborne)FB qualifying best at Runoffs 2016: 97.5% of FC's (Alex Mayer)FB qualifying best at Runoffs 2017: 97.3% of FC's (Gary Hickman)FB qualifying best at Runoffs 2018: 95.7% of FC's (J R Osborne)FB qualifying best at Runoffs 2019: 102.9% of FC's (Pete Frost)F5 race best at Runoffs 2015: 107.1% of FC's (Matthew Strand)F5 race best at Runoffs 2016: 109.5% of FC's (Steven Thompson)F5 race best at Runoffs 2017: 106.2% of FC's (Wiley Clinton McMahan)F5 race best at Runoffs 2018: 109.0% of FC's (David Lapham)F5 race best at Runoffs 2019: 104.8% of FC's (Wiley Mcmahan)F5 race best at Runoffs 2020: 105.8% of FC's (James Weida)F5 race best at Runoffs 2021: 106.4% of FC's (Sven de Vries)F5 race best at Runoffs 2022: 111.0% of FC's (Sven de Vries)F5 qualifying best at Runoffs 2015: 106.4% of FC's (W. Clint McMahan)F5 qualifying best at Runoffs 2016: 108.0% of FC's (Calvin Stewart)F5 qualifying best at Runoffs 2017: 107.1% of FC's (Wiley Clinton McMahan)F5 qualifying best at Runoffs 2018: 110.0% of FC's (Jeff Jorgenson)F5 qualifying best at Runoffs 2019: 105.5% of FC's (Wiley Mcmahan)F5 qualifying best at Runoffs 2020: 106.3% of FC's (Calvin Stewart)F5 qualifying best at Runoffs 2021: 106.0% of FC's (Ryan Mayfield)F5 qualifying best at Runoffs 2022: 107.1% of FC's (James Weida)FM race best at Runoffs 2015: 102.5% of FC's (Joseph Burton-Harris)FM race best at Runoffs 2016: 107.2% of FC's (Jacob Loomis)FM race best at Runoffs 2017: 104.4% of FC's (Jarret Voorhies)FM race best at Runoffs 2018: 104.1% of FC's (Bryce Cornet)Off the chart: FM race best at Runoffs 2019: 121.1% of FC's (Bryce Cornet)FM qualifying best at Runoffs 2015: 102.9% of FC's (Joseph Burton-Harris)FM qualifying best at Runoffs 2016: 105.0% of FC's (Jacob Loomis)FM qualifying best at Runoffs 2017: 105.1% of FC's (Jarret Voorhies)FM qualifying best at Runoffs 2018: 105.4% of FC's (Bryce Cornet)FM qualifying best at Runoffs 2019: 103.5% of FC's (Bryce Cornet)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
FCFBF5FMsolid race · dashed qualifying · each class's best lap as a share of FC's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
EventFCFBF5FM
Qual best Race best Trap Qual best Race best Trap vs FC % of FC Qual best Race best Trap vs FC % of FC Qual best Race best Trap vs FC % of FC 
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%)
2 rule changes (FC: 2)1 weight · 1 othershowhide
  • FC F2000 MZR Spec Line Clarity/Revision Requested #38927other
  • FC Adjust F2000 Metrik ZF2 weight #39612weight -20 lbs
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%)
2 rule changes (FC: 2)1 tyres & wheels · 1 weightshowhide
  • FC 9.1.1.10.h. FC Tire Rule #36533tyres & wheels
  • FC Change FF/FC Weight with Sequential Gearbox #36651weight
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%)
2 rule changes (FC: 2)2 weightshowhide
  • FC Four Pot Calipers #35481weight
  • FC Please correct omitted punctuation #34890weight
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%)
3 rule changes (FC: 3)1 engine · 1 tyres & wheels · 1 weightshowhide
  • FC Review FC Runoffs Tire Marking Rule #34274tyres & wheels
  • FC USF2000 Van Diemen with Mazda MZR LF-DE 2.0L in FC #34329weight
  • FC E&O 9.1.1.B.16.j #33634engine
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%)1:57.689James 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%)+14.003squal +7.794s111.0%qual 107.1%
11 rule changes (FC: 5, F5: 6)5 engine · 2 induction · 1 tyres & wheels · 1 wording · 2 othershowhide
  • F5 Intake Boots Correction #33028induction
  • F5 Ensure availability of ECU for Rotax engines #32695engine
  • F5 Clarify stepped exhaust header references #32743engine
  • FC Add Specification to Performance Electronics ECU for Ford Zetec #32761engine
  • F5 593 carb boot availability and oil pump clarification #32527induction
  • F5 E&O class name #32194other
  • F5 Data Box Mounting Plate #31638other
  • FC Clean up Chassis/Frame section #31867engine
  • FC Clarify Zetec ECU requirements #31554engine
  • FC Clarify composite anti-intrusion panel language #31426wording
  • FC Clarify tire marking requirements #31455tyres & wheels
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 Minor1:42.619Ryan 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 Weida+6.160squal +5.832s106.4%qual 106.0%
4 rule changes (FC: 1, F5: 3)1 engine · 1 tyres & wheels · 1 weight · 1 wordingshowhide
  • F5 Clarify allowable assisted shifting systems #30871wording
  • F5 Request to correct terminology #30976tyres & wheels
  • F5 Request to Allow Rotax 593 HO Engine #30712engine
  • FC Request for FC Weight Change #30171weight
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 Allaer2:20.954Calvin Stewart · fastest of 16 · top 5 within 1.8s2:21.391James Weida · fastest of 14 · top 5 within 1.5s143.2Aaron Ellis+7.783squal +8.310s105.8%qual 106.3%
10 rule changes (FC: 4, F5: 6)4 engine · 2 induction · 1 weight · 3 othershowhide
  • F5 Request to Update Suzuki Engine Years for F500 #29453engine
  • FC Urgent: SCCA PE3 map unsuitable #29475induction
  • FC Request for weight adjustments to equalize FC competition. #28888weight
  • 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
  • F5 Change 600cc restrictor size #27883induction
  • FC Request for Better Zetec Connecting Rods #27710engine
  • FC Add Alternate Piston #27795engine
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 Allaer1:54.469Pete Frost · only car1:57.688Pete Frost · only car145.9Pete Frost+5.514squal +3.269s104.9%qual 102.9%1:57.361Wiley Mcmahan · fastest of 15 · top 5 within 3.8s1:57.572Wiley Mcmahan · fastest of 15 · top 5 within 4.0s142.8Eric McRee+5.398squal +6.161s104.8%qual 105.5%1:55.124Bryce Cornet · fastest of 8 · top 5 within 2.3s2:15.816Bryce Cornet · fastest of 8 · top 5 within 4.9s135.7Bryce Cornet+23.642squal +3.924s121.1%qual 103.5%
3 rule changes (FC: 2, F5: 1)3 weightshowhide
  • F5 Request for Weight Increase for Motorcycle Powered Cars #27214weight +25 lbs
  • FC E&O Wiseco piston and Crower connecting rod #26659weight
  • FC Correct Wiseco piston and connecting rod #25809weight
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 Armington1:28.612J R Osborne · fastest of 7 · top 5 within 3.3s1:31.189J R Osborne · fastest of 7 · top 5 within 3.7s140.5J R Osborne-2.864squal -3.959s97.0%qual 95.7%1:41.807Jeff Jorgenson · fastest of 5 · top 5 within 6.6s1:42.491David Lapham · fastest of 5 · top 5 within 9.5s113.3David Lapham+8.438squal +9.236s109.0%qual 110.0%1:37.598Bryce Cornet · fastest of 13 · top 5 within 0.9s1:37.909Bryce Cornet · fastest of 12 · top 5 within 1.3s124.1Melvin David Kemper Jr+3.856squal +5.027s104.1%qual 105.4%
No rule changes on record between these events
Indianapolis Motor Speedway Runoffs 20172017-09-251:36.336Austin McCusker · fastest of 14 · top 5 within 2.3s1:36.890Tim Minor · fastest of 14 · top 5 within 3.8s1:33.746Gary Hickman · fastest of 18 · top 5 within 3.3s1:33.702Alex Mayer · fastest of 17 · top 5 within 3.0s-3.188squal -2.590s96.7%qual 97.3%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+5.970squal +6.800s106.2%qual 107.1%1:41.231Jarret Voorhies · fastest of 16 · top 5 within 1.7s1:41.146Jarret Voorhies · fastest of 16 · top 5 within 1.2s+4.256squal +4.895s104.4%qual 105.1%
No rule changes on record between these events
Mid-Ohio Sports Car Course Runoffs 20162016-09-191:21.962John LaRue · fastest of 7 · top 5 within 2.6s1:22.049Nigel Saurino · fastest of 7 · top 5 within 3.0s1:19.886Alex Mayer · fastest of 10 · top 5 within 1.5s1:21.015Jeremy Hill · fastest of 10 · top 5 within 1.2s-1.034squal -2.076s98.7%qual 97.5%1:28.528Calvin Stewart · fastest of 14 · top 5 within 3.9s1:29.853Steven Thompson · fastest of 12 · top 5 within 4.5s+7.804squal +6.566s109.5%qual 108.0%1:26.043Jacob Loomis · fastest of 8 · top 5 within 3.1s1:27.922Jacob Loomis · fastest of 8 · top 5 within 2.7s+5.873squal +4.081s107.2%qual 105.0%
No rule changes on record between these events
Daytona International Speedway Runoffs 20152015-09-211:54.477Yufeng Luo · fastest of 11 · top 5 within 2.5s1:55.135Yufeng Luo · fastest of 10 · top 5 within 2.1s1:50.711J R Osborne · fastest of 20 · top 5 within 1.1s1:51.616J R Osborne · fastest of 19 · top 5 within 2.1s-3.519squal -3.766s96.9%qual 96.7%2:01.824W. Clint McMahan · fastest of 16 · top 5 within 3.0s2:03.298Matthew Strand · fastest of 15 · top 5 within 4.9s+8.163squal +7.347s107.1%qual 106.4%1:57.804Joseph Burton-Harris · fastest of 10 · top 5 within 2.3s1:58.029Joseph Burton-Harris · fastest of 10 · top 5 within 1.7s+2.894squal +3.327s102.5%qual 102.9%

By track

TrackEvents Typical % of FC Best Latest 
Road America4100.0%100.0%Runoffs 2020100.0%Runoffs 2026
Virginia International Raceway3100.0%100.0%Runoffs 2019100.0%Runoffs 2023
Indianapolis Motor Speedway2100.0%100.0%Runoffs 2017100.0%Runoffs 2021
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 Raceway1100.0%100.0%Runoffs 2018100.0%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 FC'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.