BoP Lab / Buttonwillow Raceway Park

FE vs FM vs FB vs P pace at Buttonwillow Raceway Park

Lap times across years say as much about the weather as the class. % of FE is each class's best lap as a share of FE's on the same day, so the conditions drop out: 100% is level, less is quicker, and a move in it is the class getting faster or slower against the field.

Quickest here: P 1:32.872 Jim Devenport, Super Tour Feb 2025 qualifying

FEFMFBPsolid race · dashed qualifying · slower is lower

	Event	FE			FM					FB					P
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs FE	% of FE	Qual best	Race best	Trap	vs FE	% of FE	Qual best	Race best	Trap	vs FE	% of FE
	Super Tour Feb 2026 CALCL262026-02-21														1:38.716Kevin Mitz · fastest of 3 · top 3 within 3.1s+5.844s (+6.29%)	1:37.287John Manfroy · fastest of 3 · top 3 within 3.5s+3.315s (+3.53%)	160.4John Manfroy+18.7 mph (+13.2%)
9 rule changes (FE: 3, P: 6)3 weight · 2 induction · 1 engine · 1 suspension & brakes · 2 othershowhide 2026-01-01 FE FE & FE2 Rule Updates #39484engine 2026-01-01 P Request to Continue to Allow Carbon Brakes #39476suspension & brakes 2025-10-01 FE FE & FE2 Bubble Tail #38978other 2025-09-01 FE FE & FE2 Rule Updates #38901weight 2025-09-01 P 13B Rotary Engine Rules Change Request #38856induction 2025-09-01 P Add Radical Cup series Radical SR3 spec line to Table 1 #38916other 2025-09-01 P Clarify spec line cars language #38943weight 2025-08-01 P RM 25-05 - Prototype Engine Table A, 2 Cycle Restrictor Change #38929induction 2025-05-01 P Add missing punctuation marks #38150weight
	Super Tour Feb 2025 CALCL252025-02-22														1:32.872Jim Devenport · fastest of 3 · top 3 within 8.1s	1:33.972Jim Devenport · fastest of 3 · top 3 within 7.7s	141.7Jim Devenport
28 rule changes (FE: 26, P: 2)7 tyres & wheels · 5 suspension & brakes · 3 aero · 3 engine · 2 weight · 2 wording · 6 othershowhide 2025-02-01 P Correct text in engine table notes #37606engine 2025-02-01 P Update Prototype class designation #37653tyres & wheels 2024-12-01 FE Brake Line to A-Arm Covers #37110suspension & brakes 2024-09-01 FE Protest Fee Clarification #36540wording 2024-09-01 FE Update on Letter 36620 with new Hoosier Contingency Decal Info #36625tyres & wheels 2024-08-01 FE Hoosier Tire Decal Placement #36435tyres & wheels 2024-01-01 FE Update FE Rain Light Rule #34707other 2024-01-01 FE FE/FE2 rule update #35269other 2023-04-01 FE Update FE SADEV Transmission Rule #33883other 2022-10-01 FE Brake bias adjuster clarification #33084suspension & brakes 2022-10-01 FE FE Front and Rear Wing Update & Clarification #33089aero 2022-09-01 FE Engine Heat Shield & Insulation #33019engine 2022-06-01 FE Update FE/FE2 Tire Rule #32613tyres & wheels 2022-06-01 FE Master cylinder clarification #32669engine 2021-12-01 FE Two FE2 Rule Updates #31524other 2021-07-01 FE FE Tire Rule Changes #30754tyres & wheels 2021-07-01 FE Radiator Screens Clarification #30792wording 2021-06-01 FE FE Radiator Screens #30575other 2020-12-01 FE FE / FE2 Spring Updates #29689suspension & brakes 2020-10-01 FE FE Gurney Flap Spec Update #29445aero 2020-06-01 FE FE Gurney flap wicker clarification #28885aero 2020-05-01 FE FE spring rule update changed to November 1, 2020 #28814suspension & brakes 2020-01-01 FE Request for FE / FE2 preparation rules update #27722weight 2019-12-01 FE FE / FE2 Update Rules #27624weight 2019-10-01 FE FE Wet Tire E&O #27365tyres & wheels 2019-07-01 FE FE Tire Update #27029tyres & wheels 2019-05-31 FE FE Anti-Roll Bar Clarification #26912suspension & brakes 2019-05-31 FE FE / FE2 Updated Bubble Tail Rule #26913other
	Super Tour Apr 2019 ST19APR262019-04-26
1 earlier rule change on record, in force before Super Tour Apr 2019 (from 2019)1 tyres & wheelsshowhide 2019-03-01 FE Request to Update Hoosier Rain Tire Part Number for the FE cars #26235tyres & wheels

About this data

Best is the class's fastest lap in that event's qualifying or race sessions, with the driver who set it, how many cars set a time that session and how close the top five were; a best from fewer than three cars is greyed. With two or more classes, "vs" is the gap of each class's best to the first class's at the same event. "% of FE" is the class's best as a share of FE's best at the same event (100% is level, less is quicker): weather and track condition move every class together, so this compares across years where the raw times do not. It still breaks when FE's own field changes or one session was wet and another dry. Newest event first. The coloured figure under each value is the change from the previous event that has one (green is quicker, red slower). Whole laps only, so events with different sector layouts still compare. Weather and track condition are not accounted for.