BoP Lab / Classes / FF
FF vs FE2 vs SM vs P1 pace at every track
Lap times across years say as much about the weather as the class. % of FF is each class's best lap as a share of FF'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.
Closest to the field: FF 100.0% of FF Rick Payne, Daytona International Speedway Runoffs 2015 race · FE2 79.8% of FF Liam Snyder, Virginia International Raceway Runoffs 2019 race · SM 97.1% of FF Elivan Goulart, Virginia International Raceway Runoffs 2019 race · P1 73.7% of FF Todd Slusher, Virginia International Raceway Runoffs 2019 race
| Event | FF | FE2 | SM | P1 | ||||||||||||||||
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| Qual best | Race best | Trap | Qual best | Race best | Trap | vs FF | % of FF | Qual best | Race best | Trap | vs FF | % of FF | Qual best | Race best | Trap | vs FF | % of FF | |||
| Road America Runoffs 20262026-09-28 | 2:23.047David Ybarra · fastest of 20 · top 5 within 1.4s-1.858s (-1.28%) | 2:23.686Nathan Down · fastest of 20 · top 5 within 1.6s-1.855s (-1.27%) | 138.9Tazio Stefanelli+0.5 mph (+0.3%) | 2:12.326Franklin Futrelle · fastest of 8 · top 5 within 1.9s-0.149s (-0.11%) | 2:11.881Franklin Futrelle · fastest of 8 · top 5 within 1.6s-1.458s (-1.09%) | 143.5Steve Whitston-5.5 mph (-3.7%) | -11.805squal -10.721s | 91.8%qual 92.5% | 2:42.173Brett Kowalski · fastest of 34 · top 5 within 0.3s-0.938s (-0.58%) | 2:42.725Francisco Barroso · fastest of 35 · top 5 within 0.2s-1.705s (-1.04%) | 119.6Wyatt Couch+0.3 mph (+0.3%) | +19.039squal +19.126s | 113.3%qual 113.4% | |||||||
5 rule changes (FF: 2, FE2: 1, SM: 2)1 cars added · 1 tyres & wheels · 2 wording · 1 other · FF Kent 1600 compression ratio calculation parameters reorganized: bore size and valve protrusion limits moved to separate subsections for clarity. · SM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361. · SM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. · FF clarifies alternative tire eligibility: homologated 1989 or earlier with rocker or outboard suspension all four corners; push-rod/pull-rod cars may seek approval. · FE and FE2 Enterprise bubble tail part WM138014 now allowed; FE2 must use this configuration only.show
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| Road America Runoffs 20252025-09-29 | 2:24.905Jonathan Kotyk · fastest of 17 · top 5 within 1.1s+2.353s (+1.65%) | 2:25.541Calvin Kautz · fastest of 16 · top 5 within 0.5s+3.484s (+2.45%) | 138.4Tazio Stefanelli-2.3 mph (-1.6%) | 2:12.475Franklin Futrelle · fastest of 11 · top 5 within 1.4s+0.969s (+0.74%) | 2:13.339Franklin Futrelle · fastest of 10 · top 5 within 0.6s+0.591s (+0.45%) | 149.0Steve Whitston+3.7 mph (+2.6%) | -12.202squal -12.430s | 91.6%qual 91.4% | 2:43.111Bobby Gossett · fastest of 32 · top 5 within 0.3s+2.005s (+1.24%) | 2:44.430Kyle Greenhill · fastest of 28 · top 5 within 0.3s+2.944s (+1.82%) | 119.3Francisco Barroso-0.6 mph (-0.5%) | +18.889squal +18.206s | 113.0%qual 112.6% | |||||||
9 rule changes (FF: 4, FE2: 1, SM: 4)2 tyres & wheels · 1 engine · 1 weight · 3 wording · 2 other · SMX drivers must submit data acquisition files on time or face suspension and $250 fine. · SMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines. · FF adds rocker arm and outboard suspension cars option to use Hoosier bias ply slicks or VFF tyres; clarifies mixing rules. · SM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only. · FE2 allows pre-approved driver safety and comfort seat and control modifications for drivers with disabilities, per logbook. · FF adds alternative tire options for older cars with rocker arm or outboard suspension: bias ply slicks or VFF radials. · SMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation. · FF and FC sequential gearbox weight penalty reduces from 25 lbs to 10 lbs minimum weight addition. · FF Honda Fit pistons: OEM 0.25mm oversize PN 13020-RB7-Z00 or Fast Forward PN FF800-110 now both allowed; standard diameter 73.240mm (2.8835 inches), minimum weight 198.0g.show
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| Road America Runoffs 20242024-10-01 | 2:22.552Calvin Kautz · fastest of 13 · top 5 within 1.1s-0.364s (-0.25%) | 2:22.057Sebastian Mateo Naranjo · fastest of 13 · top 5 within 0.6s-2.211s (-1.53%) | 140.7Calvin Kautz+2.6 mph (+1.9%) | 2:11.506Porter Aiken · fastest of 18 · top 5 within 0.5s-1.300s (-0.98%) | 2:12.748Porter Aiken · fastest of 17 · top 5 within 2.0s-0.523s (-0.39%) | 145.3Porter Aiken+1.9 mph (+1.3%) | -9.309squal -11.046s | 93.4%qual 92.3% | 2:41.106Ethan Goulart · fastest of 49 · top 5 within 0.5s-1.103s (-0.68%) | 2:41.486Brett Kowalski · fastest of 43 · top 5 within 0.3s-2.262s (-1.38%) | 119.9Alex Bertagnoli-1.4 mph (-1.2%) | +19.429squal +18.554s | 113.7%qual 113.0% | 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%) | -21.639squal -22.076s | 84.8%qual 84.5% | ||
12 rule changes (FF: 2, SM: 4, P1: 6)2 engine · 2 weight · 7 wording · 1 other · FF EGR blanking plate rule clarified: VTEC activation valve must be retained and functioning, no modifications permitted. · SMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification. · SM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01. · SMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only. · SM and SMX now allow an alternate shifter bushing at the bottom of the shift lever. · 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. · FF Honda Fit gains Fast Forward oversize piston ring option PN FF800-100 as alternative to Riken or Nippon. · 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.show
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| Virginia International Raceway Runoffs 20232023-09-23 | 1:59.249Nolan Allaer · fastest of 8 · top 5 within 2.8s+0.034s (+0.03%) | 2:00.583Jonathan Kotyk · fastest of 8 · top 5 within 0.4s-17.775s (-12.85%) | 138.4Calvin Kautz+0.1 mph (+0.1%) | 1:50.665Charles Russell Turner · fastest of 26 · top 5 within 2.3s-0.188s (-0.17%) | 1:51.098Franklin Futrelle · fastest of 19 · top 5 within 1.4s-20.947s (-15.86%) | 141.3Franklin Futrelle-0.6 mph (-0.4%) | -9.485squal -8.584s | 92.1%qual 92.8% | 2:14.986Danny Steyn · fastest of 52 · top 5 within 0.1s+0.322s (+0.24%) | 2:16.229Julian DaCosta · fastest of 46 · top 5 within 0.3s-2.878s (-2.07%) | 120.3Jim Drago+1.1 mph (+0.9%) | +15.646squal +15.737s | 113.0%qual 113.2% | 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%) | -16.254squal -16.647s | 86.5%qual 86.0% | ||
9 rule changes (FF: 1, SM: 1, P1: 7)2 aero · 2 engine · 1 weight · 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. · FF Honda Fit engine adds Fast Forward part number alternatives for intake, exhaust, oil system, and scavenge pump components. · P1 suspension covers must have symmetrical upper and lower surfaces, no airfoil cross-sections or angled downforce. · SM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. · 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.show
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| Virginia International Raceway Runoffs 20222022-09-24 | 1:59.215Jonathan Kotyk · fastest of 13 · top 5 within 1.2s-0.348s (-0.29%) | 2:18.358Jonathan Kotyk · fastest of 12 · top 5 within 2.4s-2.116s (-1.51%) | 138.3Tim Kautz+2.2 mph (+1.6%) | 1:50.853Charles Russell Turner · fastest of 25 · top 5 within 1.1s-0.209s (-0.19%) | 2:12.045Jason Conzo · fastest of 22 · top 5 within 1.8s+19.891s (+17.74%) | 141.9Eric Cruz-0.6 mph (-0.5%) | -6.313squal -8.362s | 95.4%qual 93.0% | 2:14.664Danny Steyn · fastest of 60 · top 5 within 0.2s+0.112s (+0.08%) | 2:19.107Travis Wiley · fastest of 58 · top 5 within 0.9s+2.648s (+1.94%) | 119.2Jonathan Neudorf-0.6 mph (-0.5%) | +0.749squal +15.449s | 100.5%qual 113.0% | 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%) | -24.263squal -17.614s | 82.5%qual 85.2% | ||
4 rule changes (SM: 1, P1: 3)2 engine · 2 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. · SM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation. · P1 2-cycle 6-cylinder maximum displacement increases to 1725 cc, restrictor shrinks to 40mm, minimum weight drops to 1275 lbs.show
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| Indianapolis Motor Speedway Runoffs 20212021-09-25 | 1:44.359Jonathan Kotyk · fastest of 24 · top 5 within 1.1s-0.242s (-0.23%) | 1:55.676Jonathan Kotyk · fastest of 23 · top 5 within 1.8s+11.152s (+10.67%) | 141.6Nicholas Sheppard | 1:36.395Max Grau · fastest of 28 · top 5 within 0.7s | 1:36.655Max Grau · fastest of 28 · top 5 within 0.7s | 146.2Gray Fowler | -19.021squal -7.964s | 83.6%qual 92.4% | 1:57.695Brian Henderson · fastest of 90 · top 5 within 0.5s-0.611s (-0.52%) | 1:58.837Brian Henderson · fastest of 88 · top 5 within 0.3s-0.263s (-0.22%) | 119.8Kyle Greenhill | +3.161squal +13.336s | 102.7%qual 112.8% | 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 | -26.451squal -15.348s | 77.1%qual 85.3% | ||
15 rule changes (FF: 3, SM: 1, P1: 11)2 cars added · 2 engine · 10 wording · 1 other · 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. · FF block relief permitted only as needed to fit an allowed crankshaft. · 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. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. · 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. · FF class cylinder head now permits optional coolant bleed line pipe thread fitting to swirl tower. · FF Honda LC1 ECU supplied by HPD is permitted effective 12/1/2020 with HPD lambda sensor.show
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| Road America Runoffs 20202020-10-02 | 2:22.916Simon Sikes · fastest of 14 · top 5 within 1.6s | 2:24.268Jeffrey Bartz · fastest of 14 · top 5 within 0.4s | 138.1Jeffrey Bartz | 2:12.806Scott Rettich · fastest of 25 · top 5 within 0.6s | 2:13.271Owen McAllister · fastest of 23 · top 5 within 0.7s | 143.4Owen McAllister | -10.997squal -10.110s | 92.4%qual 92.9% | 2:42.209Kyle Greenhill · fastest of 77 · top 5 within 0.5s | 2:43.748Preston Pardus · fastest of 75 · top 5 within 1.0s | 121.3Kyle Greenhill | +19.480squal +19.293s | 113.5%qual 113.5% | 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 | -22.398squal -21.815s | 84.5%qual 84.7% | ||
12 rule changes (FF: 4, FE2: 2, SM: 2, P1: 4)3 engine · 1 induction · 1 removed · 1 suspension & brakes · 1 tyres & wheels · 1 weight · 4 wording · SM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A. · FE2 oil cooler rule clarified: Setrab 50-625-7612 or any cooler with max core 13 inches wide by 6.5 inches high allowed. · FF Honda LC1 ECU implementation date clarified to pending, contingent on SCCA receiving sufficient support materials. · SM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure. · P1 intake manifolds unrestricted unless engine requires flat plate restrictor; no plenums or balance pipes on restricted individual runner manifolds. · FF Kent Engine alternator becomes optional instead of not required. · FF permits HPD LC1 ECU with lambda sensor; E1 ECU no longer supported but existing units may continue. · FF rain tyres now allow Hoosier W3 Radial 185/60R13 front and 205/60R13 rear. · 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. · FE minimum weight rises to 1270 lbs; FE2 minimum weight rises to 1270 lbs; new spring options added; tire warmers prohibited.show
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| Virginia International Raceway Runoffs 20192019-10-05 | 1:59.563Tyler O'Connor · fastest of 14 · top 5 within 1.4s | 2:20.474Jonathan Kotyk · fastest of 14 · top 5 within 6.3s | 136.2Derek Ketchie | 1:51.062Liam Snyder · fastest of 20 · top 5 within 1.3s | 1:52.154Liam Snyder · fastest of 19 · top 5 within 0.7s | 142.6Robert Vanman | -28.320squal -8.501s | 79.8%qual 92.9% | 2:14.552Todd Buras · fastest of 60 · top 5 within 0.2s | 2:16.459Elivan Goulart · fastest of 56 · top 5 within 0.4s | 119.8Jim Drago | -4.015squal +14.989s | 97.1%qual 112.5% | 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 | -36.976squal -16.889s | 73.7%qual 85.9% | ||
21 rule changes (FF: 3, SM: 4, P1: 14)1 aero · 1 cars added · 1 engine · 15 wording · 3 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. · SM fuel pump and filter now permitted as Mazda or OEM equivalent part. · FF Honda Fit cylinder honing increased to 73.315mm and oversize pistons PN 13020-RB7-Z00 now permitted with matching ring packs. · FF intake manifold thermal wrap now permitted if easily removable for inspection; no coating allowed. · FF clarifies coolant and oil catch tank capacity requirements: coolant minimum one U.S. pint, oil minimum one U.S. quart per system. · P1 engine table reference corrected from 'above' to 'below'; ETC/FBW/DBW throttle wording clarified on sensor and fail-safe requirements. · SM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified. · SM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted. · SM tire tread protrusion language removed from GCR 9.1.7.C.5. · 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.show
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| Sonoma Raceway Runoffs 20182018-10-10 | 1:41.612Jonathon Kotyk · fastest of 22 · top 5 within 1.7s | 1:42.049Jonathon Kotyk · fastest of 22 · top 5 within 1.3s | 115.7Denny Renfrow | 1:35.040Flinn Lazier · fastest of 9 · top 5 within 1.5s | 1:35.563Flinn Lazier · fastest of 9 · top 5 within 1.7s | 126.8Scott Rettich | -6.486squal -6.572s | 93.6%qual 93.5% | 1:54.355Ken Sutherland · fastest of 48 · top 5 within 0.7s | 1:55.278Michael Carter · fastest of 48 · top 5 within 0.3s | 102.2Danny Steyn | +13.229squal +12.743s | 113.0%qual 112.5% | 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 | -13.263squal -13.898s | 87.0%qual 86.3% | ||
| No rule changes on record between these events | ||||||||||||||||||||
| Indianapolis Motor Speedway Runoffs 20172017-09-25 | 1:44.601Zach Holden · fastest of 36 · top 5 within 1.2s | 1:44.524Jonathon Kotyk · fastest of 36 · top 5 within 0.5s | 1:58.306Chris Haldeman · fastest of 86 · top 5 within 0.5s | 1:59.100Michael Gagliardo · fastest of 83 · top 5 within 0.6s | +14.576squal +13.705s | 113.9%qual 113.1% | 1:30.794Jim Devenport · fastest of 19 · top 5 within 2.8s | 1:31.499Jim Devenport · fastest of 16 · top 5 within 2.2s | -13.025squal -13.807s | 87.5%qual 86.8% | ||||||||||
| No rule changes on record between these events | ||||||||||||||||||||
| Mid-Ohio Sports Car Course Runoffs 20162016-09-19 | 1:29.213Neil Verhagen · fastest of 14 · top 5 within 2.1s | 1:30.133Neil Verhagen · fastest of 14 · top 5 within 1.4s | 1:40.514Justin Hille · fastest of 45 · top 5 within 0.3s | 1:40.764Michael Carter · fastest of 44 · top 5 within 0.3s | +10.631squal +11.301s | 111.8%qual 112.7% | 1:17.308James Devenport · fastest of 14 · top 5 within 2.7s | 1:19.407Gianpaolo Ciancimino · fastest of 13 · top 5 within 1.8s | -10.726squal -11.905s | 88.1%qual 86.7% | ||||||||||
| No rule changes on record between these events | ||||||||||||||||||||
| Daytona International Speedway Runoffs 20152015-09-21 | 2:02.489Tim Kautz · fastest of 25 · top 5 within 1.1s | 2:03.383Rick Payne · fastest of 22 · top 5 within 0.8s | 2:18.661Andrew Carbonell · fastest of 62 · top 5 within 0.6s | 2:24.067Todd Lamb · fastest of 59 · top 5 within 0.8s | +20.684squal +16.172s | 116.8%qual 113.2% | 1:49.219Jim Downing · fastest of 9 · top 5 within 2.2s | 1:49.792Gianpaolo Ciancimino · fastest of 10 · top 5 within 1.7s | -13.591squal -13.270s | 89.0%qual 89.2% | ||||||||||
By track
| Track | Events | Typical % of FF | Best | Latest |
|---|---|---|---|---|
| Road America | 4 | 100.0% | 100.0%Runoffs 2020 | 100.0%Runoffs 2026 |
| Virginia International Raceway | 3 | 100.0% | 100.0%Runoffs 2019 | 100.0%Runoffs 2023 |
| Indianapolis Motor Speedway | 2 | 100.0% | 100.0%Runoffs 2017 | 100.0%Runoffs 2021 |
| Daytona International Speedway | 1 | 100.0% | 100.0%Runoffs 2015 | 100.0%Runoffs 2015 |
| Mid-Ohio Sports Car Course | 1 | 100.0% | 100.0%Runoffs 2016 | 100.0%Runoffs 2016 |
| Sonoma Raceway | 1 | 100.0% | 100.0%Runoffs 2018 | 100.0%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 FF'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.