BoP Lab / Buttonwillow Raceway Park

F5 vs FB vs SRF vs GT3 pace at Buttonwillow Raceway Park

Quickest here: F5 1:51.129 Jeff Jorgenson, Super Tour Apr 2017 race · FB 1:38.870 Gary Hickman, Super Tour Apr 2018 race · SRF 1:44.060 Vince Balch, Super Tour Apr 2017 qualifying · GT3 1:40.093 Michael Lewis, Super Tour Apr 2018 race

Lap times% of F5

F5FBSRFGT3solid race · dashed qualifying · slower is lower

F5FBSRFGT3solid race · dashed qualifying · each class's best lap as a share of F5's at the same event (the reference class, changeable above); 100% is level, higher is quicker

	Event	F5			FB					SRF					GT3
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs F5	% of F5	Qual best	Race best	Trap	vs F5	% of F5	Qual best	Race best	Trap	vs F5	% of F5
	Super Tour Feb 2020 ST20FEB212020-02-21														1:50.937Michael Lewis · fastest of 10 · top 5 within 5.7s-0.936s (-0.84%)	1:51.160Michael Lewis · fastest of 11 · top 5 within 3.8s-3.520s (-3.07%)	139.3Taz Harvey+16.7 mph (+13.6%)
18 rule changes (F5: 2, SRF: 5, GT3: 11)5 induction · 4 cars added · 2 weight · 1 aero · 1 engine · 1 suspension & brakes · 1 tyres & wheels · 3 other · GT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications. · F500 Honda CBR600RR, Suzuki GSXR600, Yamaha R6 restrictor reduced to 28mm from 29mm. · GTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo. · F500 Honda CBR600RR, Suzuki GSXR600, and Yamaha R6 minimum weights increase to 900 lbs. · GTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. · GTX adds Ligier JS2 R classification with restrictor and minimum weight.showhide 2020-02-01 GT3 Windshield Clips #27323otheraddedGT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications. 2020-01-01 F5 Change 600cc restrictor size #27883inductionslower · inductionF500 Honda CBR600RR, Suzuki GSXR600, Yamaha R6 restrictor reduced to 28mm from 29mm. 2020-01-01 GT3 Request Factory Five Daytona coupe classification #26308cars addedaddedGTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo. 2020-01-01 GT3 Request restrictor size change request #26958induction 2020-01-01 GT3 Request to Classify Alfa Romeo 4C #27322cars added 2020-01-01 GT3 Request for Mazda 2.5l MZR/L5-VE #27570induction -245 lbs 2020-01-01 GT3 GT3 turbo engines add Honda #28033induction 2020-01-01 GT3 GT3 wing end plate #28035aero 202-01-01 SRF SRF Rain / Brake Rule - BoD approved as follows #34958suspension & brakes 2019-12-01 GT3 Request to Add SR16VE to GT-3 Spec Lines #27357cars added 2019-12-01 SRF SRF Tire Warmer Rule #27622tyres & wheels 2019-12-01 SRF SRF / SRF3 Nose Weight Reduction #27706weight 2019-12-01 SRF SRF / SRF3 Majors & Regional Class Updates #27723other 2019-08-31 F5 Request for Weight Increase for Motorcycle Powered Cars #27214weight +25 lbsslower · weightF500 Honda CBR600RR, Suzuki GSXR600, and Yamaha R6 minimum weights increase to 900 lbs. 2019-08-31 GT3 Requesting Increase in Choke Diameter for Mazda 12A Bridgeport #27043induction 2019-07-01 SRF SRF Dash Windscreen Kit #27028other 2019-05-01 GT3 Request GTX Fuel injection for previous GT-1 tube frame cars #26141engineadded · engineGTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. 2019-05-01 GT3 Request to Classify Ligier JS2 R #26535cars addedaddedGTX adds Ligier JS2 R classification with restrictor and minimum weight.
	Super Tour Apr 2019 ST19APR262019-04-26														1:51.873Michael Lewis · fastest of 11 · top 5 within 6.2s+0.532s (+0.48%)	1:54.680Michael Lewis · fastest of 10 · top 5 within 2.9s+14.587s (+14.57%)	122.7Michael Lewis
5 rule changes (GT3: 5)2 weight · 1 cars added · 1 wording · 1 other · GT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate. · GTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs.showhide 2019-04-01 GT3 26076 revised Spec line chart #26528weight 2019-04-01 GT3 Request Ride Height Clarification #26600wordingfasterGT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate. 2019-03-01 GT3 Request clarification on bridge porting for rotary #26076weight 2019-03-01 GT3 Request to add 4G69 Mitsubishi #26154cars added 2019-01-01 GT3 GTX Homologation table update #26034otherunclearGTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs.
	Super Tour Apr 2018 BUTTRA182018-04-27				1:39.142Gary Hickman · fastest of 2-3.130s (-3.06%)	1:38.870Gary Hickman · fastest of 2-1.241s (-1.24%)									1:51.341Michael Lewis · fastest of 7 · top 5 within 6.9s+1.772s (+1.62%)	1:40.093Michael Lewis · fastest of 6 · top 5 within 16.8s-12.227s (-10.89%)
No rule changes on record between these events
	Super Tour Apr 2017 BUTTRA172017-04-28	1:52.268Jeff Jorgenson · fastest of 2	1:51.129Jeff Jorgenson · fastest of 2		1:42.272John LaBrie · fastest of 2	1:40.111Gary Hickman · fastest of 2		-11.018squal -9.996s	90.1%qual 91.1%	1:44.060Vince Balch · fastest of 8 · top 5 within 18.6s	2:01.122Mike Miserendino · fastest of 7 · top 5 within 1.8s		+9.993squal -8.208s	109.0%qual 92.7%	1:49.569Collin Jackson · fastest of 5 · top 5 within 13.8s	1:52.320Collin Jackson · fastest of 5 · top 5 within 12.1s		+1.191squal -2.699s	101.1%qual 97.6%

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 F5" is the class's best as a share of F5'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 F5'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.