BoP Lab / Classes / P1

P1 pace at every track

Lap times across years say as much about the weather as the class. % of the field is each class's best lap as a share of the field's on the same day (every class that ran that day but the ones shown, each scaled by its usual pace against SM and averaged, with each shown class's own track character taken out, so one figure reads the same across years and tracks), 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)

AS +B-Spec +EP +FA +FC +FE2 +FF +FP +FV +FX +GT1 +GT2 +GTX +HP +P +P1×P2 +SM +SMX +SRF3 +STL +STU +T1 +T2 +T3 +T4 +Show 50 inactive classes

Series Runoffs Super Tour Both

Reference · what % is measured against, 10 eventsall classes that day, as if at an average track

Tracks · untick to narrow Auto Club Speedway Blackhawk Farms Raceway Buttonwillow Raceway Park Circuit of the Americas Daytona International Speedway Grattan Raceway Homestead-Miami Speedway Indianapolis Motor Speedway Laguna Seca Michelin Raceway Road Atlanta Mid-Ohio Sports Car Course New Jersey Motorsports Park NOLA Motorsports Park Pacific Raceways Pittsburgh International Race Complex Portland International Raceway Pueblo Motorsports Park Road America Sebring International Raceway Sonoma Raceway Thunderhill Raceway Park Virginia International Raceway Watkins Glen International Willow Springs Raceway

Closest to the field: P1 74.0% of the field Lee Alexander, Indianapolis Motor Speedway Runoffs 2021 race

% of the fieldLap times

P1solid race · dashed qualifying · slower is lowerVirginia International RacewayIndianapolis Motor SpeedwayRoad AmericaDaytona International SpeedwayMid-Ohio Sports Car CourseSonoma Raceway

P1solid race · dashed qualifying · each class's best lap as a share of the field's at the same event (the field index, changeable above); 100% is level, less is quicker, so up the chart is quickerVirginia International RacewayIndianapolis Motor SpeedwayRoad AmericaDaytona International SpeedwayMid-Ohio Sports Car CourseSonoma Raceway

	Event	P1
	Event	Qual best	Race best	Trap	% of the field
	Road America Runoffs 20242024-10-01	2:00.476Chip Romer · fastest of 12 · top 5 within 1.5s-0.625s (-0.52%)	2:00.418Matt Romer · fastest of 9 · top 5 within 2.1s-1.452s (-1.19%)	168.3Jason Miller+8.7 mph (+5.4%)	76.7%qual 77.1%
6 rule changes (P1: 6)2 weight · 4 wording · P1 engine approval process wording clarified; unspecified engines need case-by-case Board review. · P1 removes redundant effective date language from ECU stall prohibition rule. · P1 Honda K20A-FD2 engine terminology corrected from 'spec' to proper series designation; FIA certification documentation requirement removed. · P1 Engine Table line H restrictor grows to 32 mm, weight rises to 1450 lbs; line I restrictor to 31 mm, weight to 1475 lbs. · P1 Group CN Honda K20A-FD2 removes engine modification restrictions; CRB may add intake restrictor if needed.showhide 2024-05-01 Update GCR section 9.1.8.B.J.7 #35907wordingwordingP1 engine approval process wording clarified; unspecified engines need case-by-case Board review. 2024-03-01 Remove redundant effective date language in GCR 9.1.8.B.J.4 #35693wordingwordingP1 removes redundant effective date language from ECU stall prohibition rule. 2024-03-01 Correct engine series terminology #35694wordingwordingP1 Honda K20A-FD2 engine terminology corrected from 'spec' to proper series designation; FIA certification documentation requirement removed. 2024-01-01 Please correct omitted punctuation #34890weight 2024-01-01 Adjust restrictors and weights for Engine Table lines H and I #35229weightslowerweightP1 Engine Table line H restrictor grows to 32 mm, weight rises to 1450 lbs; line I restrictor to 31 mm, weight to 1475 lbs. 2024-01-01 Revise Group CN Honda K20A-FD2 Spec Line #35337wordingunclearP1 Group CN Honda K20A-FD2 removes engine modification restrictions; CRB may add intake restrictor if needed.
	Virginia International Raceway Runoffs 20232023-09-23	1:42.602Todd Vanacore · fastest of 10 · top 5 within 0.9s+1.001s (+0.99%)	1:44.329Todd Vanacore · fastest of 9 · top 5 within 0.7s-9.766s (-8.56%)	158.5Jason Miller+1.2 mph (+0.8%)	77.3%qual 76.6%
7 rule changes (P1: 7)2 aero · 1 engine · 4 wording · P1 SIR testing: vehicle deemed compliant if it stalls within 3 seconds of the stall test. · P1 intake restrictor rule clarified: flat plate, venturi, or Single Inlet Restrictor required; all intake air must pass through. · P1 ducted air rule clarified: top-exit ducted air must pass through heat exchanger, except cockpit opening and engine bay vents. · P1 aero height limit, front/rear overhang, and cockpit dimensions corrected to metric-inch equivalents. · P1 suspension covers must have symmetrical upper and lower surfaces, no airfoil cross-sections or angled downforce. · P1 aerodynamic devices may not extend more than 1cm below lower surfaces rear of front axle; body panels covering suspension must not be airfoil-shaped or create downforce. · P1 forced induction prohibited: turbocharging and supercharging not allowed.showhide 2023-07-01 SIR Testing #34354wordingwordingP1 SIR testing: vehicle deemed compliant if it stalls within 3 seconds of the stall test. 2023-07-01 E&O Single Inlet Restrictor abbreviation, etc. #34369wordingwordingP1 intake restrictor rule clarified: flat plate, venturi, or Single Inlet Restrictor required; all intake air must pass through. 2023-07-01 E&O Clean up ducted air provision #34410wordingwordingP1 ducted air rule clarified: top-exit ducted air must pass through heat exchanger, except cockpit opening and engine bay vents. 2023-04-01 E&O - Correct dimensional equivalents #34018wordingwordingP1 aero height limit, front/rear overhang, and cockpit dimensions corrected to metric-inch equivalents. 2023-03-01 November 2022 Rules Clarification for Suspension Covers #33615aerosloweraeroP1 suspension covers must have symmetrical upper and lower surfaces, no airfoil cross-sections or angled downforce. 2022-11-01 Clarify body panel coverage of suspension components #33318aeroaeroP1 aerodynamic devices may not extend more than 1cm below lower surfaces rear of front axle; body panels covering suspension must not be airfoil-shaped or create downforce. 2022-10-01 E&O clarification regarding forced induction #33123engineremovedengineP1 forced induction prohibited: turbocharging and supercharging not allowed.
	Virginia International Raceway Runoffs 20222022-09-24	1:41.601Todd Slusher · fastest of 9 · top 5 within 2.3s-1.073s (-1.05%)	1:54.095John Mcaleer · fastest of 9 · top 5 within 1.4s+10.597s (+10.24%)	157.2Jason Miller+1.3 mph (+0.8%)	76.3%qual 76.3%
3 rule changes (P1: 3)2 engine · 1 wording · P1 motorcycle-based engines with individual throttle bodies must use flat plate intake restrictors within 4 inches of primary butterfly. · P1 bodywork rules clarified: cycle fenders prohibited, side body minimum height at front axle centerline, air ducting for downforce banned. · P1 2-cycle 6-cylinder maximum displacement increases to 1725 cc, restrictor shrinks to 40mm, minimum weight drops to 1275 lbs.showhide 2022-08-01 Clarify authorization to use flat plate intake restrictor #32964engineaddedengineP1 motorcycle-based engines with individual throttle bodies must use flat plate intake restrictors within 4 inches of primary butterfly. 2022-05-01 E&O Clarification of Bodywork Rules #32468wordingwordingP1 bodywork rules clarified: cycle fenders prohibited, side body minimum height at front axle centerline, air ducting for downforce banned. 2022-01-01 Displacement & Weight Change Request for 2-Cycle 6 Cylinder #31609enginefasterengineP1 2-cycle 6-cylinder maximum displacement increases to 1725 cc, restrictor shrinks to 40mm, minimum weight drops to 1275 lbs.
	Indianapolis Motor Speedway Runoffs 20212021-09-25	1:29.011Lee Alexander · fastest of 13 · top 5 within 2.5s-1.783s (-1.96%)	1:29.225Lee Alexander · fastest of 12 · top 5 within 3.5s-2.274s (-2.49%)	160.1Jason Miller	74.0%qual 76.3%
11 rule changes (P1: 11)2 cars added · 2 engine · 7 wording · P1 creates separate spec lines H and I for 2000cc and 2300cc engines at 1400 and 1445 lbs minimum weight respectively. · P1 Staudacher may run 950 lbs minimum weight with 38.5mm flat plate intake restrictor, removing prior weight-linked restrictor rule. · P1 adds 1355cc motorcycle-based engine line C at 1075 lbs minimum weight, no restrictor required. · P1 cockpit opening section allows tonneau covers to meet minimum dimensions; wording clarified on equipment attachment. · P1 Staudacher 1005cc homologated before 1-1-2014 may run 38.5mm flat plate intake restrictor at 950 lbs minimum weight. · P1 Spec Line C: FPIR not required at 1150 lbs, 1355cc max may run without FPIR at 1075 lbs. Spec Line G: up to 2000cc runs 30mm SIR at 1400 lbs, 2300cc runs 30mm SIR at 1445 lbs. · P1 classes B, C, D maximum valves per cylinder set to 4, previously unspecified. · P1 Spec Line A clarifies carburetor induction only, one per cylinder, balance tubes not allowed. · P1 Spec Line H notes clarify peripheral port or bridgeport allowed; wording only. · P1 Elan DP02-spec Mazda MZR sealed engine option removed effective 3/1/2021. · P1 Engine Table Spec Lines C and G change 'inlet restrictor' to 'intake restrictor' terminology.showhide 2021-09-01 Move 2000cc and 2300cc engine options to individual spec lines #31012cars addedaddedP1 creates separate spec lines H and I for 2000cc and 2300cc engines at 1400 and 1445 lbs minimum weight respectively. 2021-09-01 E&O Spec Line B notes #31095wordingwordingP1 Staudacher may run 950 lbs minimum weight with 38.5mm flat plate intake restrictor, removing prior weight-linked restrictor rule. 2021-08-01 Add 1355cc spec line #30890cars addedaddedP1 adds 1355cc motorcycle-based engine line C at 1075 lbs minimum weight, no restrictor required. 2021-05-01 E&O tonneau cover provision in cockpit opening section #30458wordingwordingP1 cockpit opening section allows tonneau covers to meet minimum dimensions; wording clarified on equipment attachment. 2021-05-01 Update Spec Line B Notes #30498wordingwordingP1 Staudacher 1005cc homologated before 1-1-2014 may run 38.5mm flat plate intake restrictor at 950 lbs minimum weight. 2021-05-01 Update Spec Lines C and G notes #30499wordingwordingP1 Spec Line C: FPIR not required at 1150 lbs, 1355cc max may run without FPIR at 1075 lbs. Spec Line G: up to 2000cc runs 30mm SIR at 1400 lbs, 2300cc runs 30mm SIR at 1445 lbs. 2021-05-01 E&O Maximum Valves Per Cylinder #30559engineengineP1 classes B, C, D maximum valves per cylinder set to 4, previously unspecified. 2021-04-01 Clean up Spec Line A notes section #30424wordingwordingP1 Spec Line A clarifies carburetor induction only, one per cylinder, balance tubes not allowed. 2021-04-01 Clean up Spec Line H notes section #30425wordingwordingP1 Spec Line H notes clarify peripheral port or bridgeport allowed; wording only. 2021-03-01 DP02 Sealed 2ltr Engine Option #30038engineremovedengineP1 Elan DP02-spec Mazda MZR sealed engine option removed effective 3/1/2021. 2021-03-01 E&O restrictor terminology #30285wordingwordingP1 Engine Table Spec Lines C and G change 'inlet restrictor' to 'intake restrictor' terminology.
	Road America Runoffs 20202020-10-02	2:01.101James French · fastest of 18 · top 5 within 1.1s	2:01.870James French · fastest of 17 · top 5 within 1.8s	159.7David Locke	76.7%qual 77.0%
4 rule changes (P1: 4)1 engine · 1 induction · 1 removed · 1 wording · P1 intake manifolds unrestricted unless engine requires flat plate restrictor; no plenums or balance pipes on restricted individual runner manifolds. · P1 sealed 2.0L Elan DP02-spec Mazda option removal date extended from 1/1/2020 to 1/1/2021. · P1 sealed 2.0 MZR engine removed effective 1/1/2020; competitors may run it under Spec Line G. · P1 Spec Line F: Restricted 2.0L Group becomes CN-spec Honda K20A-FD2, 2000cc, 1400 lbs minimum.showhide 2020-05-01 E&O minimum weights and intake manifolds #28731inductioninductionP1 intake manifolds unrestricted unless engine requires flat plate restrictor; no plenums or balance pipes on restricted individual runner manifolds. 2020-02-01 Extend date for removing sealed DP02-spec 2.0L option #28046wordingunclearP1 sealed 2.0L Elan DP02-spec Mazda option removal date extended from 1/1/2020 to 1/1/2021. 2020-01-01 Remove sealed DP02-spec 2.0 MZR spec #26753removedremovedP1 sealed 2.0 MZR engine removed effective 1/1/2020; competitors may run it under Spec Line G. 2020-01-01 Update Revised Spec Line F #27745engineengineP1 Spec Line F: Restricted 2.0L Group becomes CN-spec Honda K20A-FD2, 2000cc, 1400 lbs minimum.
	Virginia International Raceway Runoffs 20192019-10-05	1:42.674Todd Slusher · fastest of 14 · top 5 within 1.5s	1:43.498Todd Slusher · fastest of 13 · top 5 within 1.0s	155.9Jim Devenport	75.6%qual 77.0%
14 rule changes (P1: 14)1 cars added · 12 wording · 1 other · P1 traction control prohibited. · P1 permits mechanical, solenoid, and air-shifters; prohibits electronic pre-selection and multi-wheel power. · P1 minimum bodywork height rule moved and restated with new 115cm aerodynamic part height limit. · P1 consolidates fender louver rules into one section; removes duplicate allowance for louvers and clarifies brake and engine air ducts are permitted. · P1 anti-intrusion panels now allowed anywhere on chassis sides instead of specified locations. · P1 bodywork wording clarified: comfort and safety for driver and passenger or driver only. · P1 Engine Table reference cleaned up; no performance change. · P1 Mazda Renesis Rotary engine spec line removed from Engine Table. · P1 Staudacher and Honda K20A-FD2 engine table wording clarified; no performance change. · P1 closed cockpit single-seat cars remain prohibited; rule moved from subsection J.5 to B.4. · P1 engine table reference corrected from 'above' to 'below'; ETC/FBW/DBW throttle wording clarified on sensor and fail-safe requirements. · P1 removes TIR inlet restrictor option; deletes requirement for single turbo/supercharger unit with single restrictor. · P1 CN-spec Honda K20A-FD2 clarified: stock OEM parts required, no machining allowed. · P1 engine rules correct grammar and remove head designs from specification table.showhide 2019-08-01 E&O Transmissions #27098wordingwordingP1 traction control prohibited. 2019-07-01 E&O Transmissions #27005otheraddedP1 permits mechanical, solenoid, and air-shifters; prohibits electronic pre-selection and multi-wheel power. 2019-07-01 Move minimum height provision to #27031wordingwordingP1 minimum bodywork height rule moved and restated with new 115cm aerodynamic part height limit. 2019-07-01 Remove duplicative fender louver provision #27033wordingwordingP1 consolidates fender louver rules into one section; removes duplicate allowance for louvers and clarifies brake and engine air ducts are permitted. 2019-05-31 Missing word E&O #26919wordingwordingP1 anti-intrusion panels now allowed anywhere on chassis sides instead of specified locations. 2019-05-31 E&O correction to GCR 9.1.8.C.C. #26927wordingwordingP1 bodywork wording clarified: comfort and safety for driver and passenger or driver only. 2019-05-01 Clean up reference to engine table #26648wordingwordingP1 Engine Table reference cleaned up; no performance change. 2019-05-01 Remove redundant spec line #26692cars addedremovedcars addedP1 Mazda Renesis Rotary engine spec line removed from Engine Table. 2019-04-01 Clean Up Engine Table Language #26590wordingwordingP1 Staudacher and Honda K20A-FD2 engine table wording clarified; no performance change. 2019-03-01 Move single-seat closed cockpit provision to #26376wordingwordingP1 closed cockpit single-seat cars remain prohibited; rule moved from subsection J.5 to B.4. 2019-02-01 Correct errors in GCR section 9.1.8.C.J #26144wordingwordingP1 engine table reference corrected from 'above' to 'below'; ETC/FBW/DBW throttle wording clarified on sensor and fail-safe requirements. 2019-01-01 Remove redundant inlet restrictor provisions #25877wordingwordingP1 removes TIR inlet restrictor option; deletes requirement for single turbo/supercharger unit with single restrictor. 2019-01-01 Clarify Honda K20A-FD2 parts requirement #25949wordingwordingP1 CN-spec Honda K20A-FD2 clarified: stock OEM parts required, no machining allowed. 2019-01-01 Correct GCR section 9.1.8.C.J errors #25966wordingwordingP1 engine rules correct grammar and remove head designs from specification table.
	Sonoma Raceway Runoffs 20182018-10-10	1:27.714Todd Slusher · fastest of 19 · top 5 within 2.1s	1:28.786Perry Richardson · fastest of 19 · top 5 within 0.9s	144.0Johnnie Crean	76.1%qual 78.2%
No rule changes on record between these events
	Indianapolis Motor Speedway Runoffs 20172017-09-25	1:30.794Jim Devenport · fastest of 19 · top 5 within 2.8s	1:31.499Jim Devenport · fastest of 16 · top 5 within 2.2s		77.7%qual 77.8%
No rule changes on record between these events
	Mid-Ohio Sports Car Course Runoffs 20162016-09-19	1:17.308James Devenport · fastest of 14 · top 5 within 2.7s	1:19.407Gianpaolo Ciancimino · fastest of 13 · top 5 within 1.8s		76.0%qual 74.9%
No rule changes on record between these events
	Daytona International Speedway Runoffs 20152015-09-21	1:49.219Jim Downing · fastest of 9 · top 5 within 2.2s	1:49.792Gianpaolo Ciancimino · fastest of 10 · top 5 within 1.7s		78.3%qual 78.6%

By track

Track	Events	Typical % of the field	Best	Latest
Virginia International Raceway	3	76.3%	75.6%Runoffs 2019	77.3%Runoffs 2023
Indianapolis Motor Speedway	2	74.0%	74.0%Runoffs 2021	74.0%Runoffs 2021
Road America	2	76.7%	76.7%Runoffs 2020	76.7%Runoffs 2024
Daytona International Speedway	1	78.3%	78.3%Runoffs 2015	78.3%Runoffs 2015
Mid-Ohio Sports Car Course	1	76.0%	76.0%Runoffs 2016	76.0%Runoffs 2016
Sonoma Raceway	1	76.1%	76.1%Runoffs 2018	76.1%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 the field's best on the same day (every class that ran that day but the ones shown, each scaled by its usual pace against SM and averaged, with each shown class's own track character taken out, so one figure reads the same across years and tracks): the weather and the day cancel out, so one figure compares across years where lap times cannot, and across tracks too, since the class's own character at each track is taken out. A track with only one or two events on record is corrected less, since there is less to go on. A best from fewer than three cars is greyed. The rule changes that took effect between two events are folded between their rows.