BoP Lab / Classes / STL
STL 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.
Closest to the field: STL 85.9% of the field Danny Steyn, Virginia International Raceway Runoffs 2022 race
| Event | STL | |||||
|---|---|---|---|---|---|---|
| Qual best | Race best | Trap | % of the field | |||
| Road America Runoffs 20262026-09-28 | 2:30.537Derek Ketchie · fastest of 16 · top 5 within 2.9s-1.528s (-1.00%) | 2:30.657Danny Steyn · fastest of 16 · top 5 within 0.6s-1.470s (-0.97%) | 134.8Mike Taylor+2.6 mph (+2.0%) | 94.8%qual 94.9% | ||
4 rule changes (STL: 4)2 cars added · 1 weight · 1 wording · STL removes Mazda MX-5 Cup entirely; renames Spec MX5 Challenge to Spec MX5; renames Global Cup to MX-5 Cup (16-18); removes Global Cup (2019). · STL, STU weight calculation procedure clarified: positive percentages added first, negative subtracted second, then fixed weights applied. · STL adds Mazda BP 1.6, 1600cc, minimum weight 2160 lbs. · STL minimum weights increase across all engine sizes, 1300cc to 1850cc up to 195–250 lbs.show
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| Road America Runoffs 20252025-09-29 | 2:32.065Jose Osiris Pena · fastest of 14 · top 5 within 3.4s+2.002s (+1.33%) | 2:32.127Jose Osiris Pena · fastest of 13 · top 5 within 2.4s+1.882s (+1.25%) | 132.2Jon Sewell-2.1 mph (-1.5%) | 95.3%qual 96.1% | ||
3 rule changes (STL: 3)1 cars added · 1 weight · 1 wording · Lotus Evora GT4 minimum weight drops to 2700 lbs; Elise Cup R to 2250 lbs; Elise SC and Exige SC to 2450–2550 lbs. · STL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1; mandatory component spec list removed, alternative tires only allowed. · STL STU Mazda Miata alternate front hubs Mazda Motorsports Development Part #0000-04-5HUB-S1 approved.show
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| Road America Runoffs 20242024-10-01 | 2:30.063Joe Moser · fastest of 18 · top 5 within 3.7s-1.357s (-0.90%) | 2:30.245Joe Moser · fastest of 16 · top 5 within 4.2s-1.870s (-1.23%) | 134.3Joe Moser+1.3 mph (+1.0%) | 94.9%qual 95.2% | ||
4 rule changes (STL: 4)2 engine · 1 aero · 1 weight · STL and STU now permit electric power steering pumps, OEM electric-assisted steering, or column-mounted electric steering assist systems. · STL normally aspirated minimum weights reduced: 1900cc to 2540 lbs, 1950cc to 2583 lbs, 2000cc to 2625 lbs; short-wheelbase FWD adds 1.25%; Honda B16/B17/B18C1 throttle to 51mm, B18C Type R and Mazda MZR to 50mm. · STL Mazda 12A: 5th and 6th intake port actuators and valves may no longer be removed or disabled. · STL 79-85 RX7 12A now allows auto-type 2 bbl carburetor with 42mm choke on dual-y manifold, not just stock Nikki.show
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| Virginia International Raceway Runoffs 20232023-09-23 | 2:05.779Danny Steyn · fastest of 22 · top 5 within 3.4s+0.305s (+0.24%) | 2:06.682Joe Moser · fastest of 20 · top 5 within 1.5s-1.150s (-0.90%) | 131.8Danny Steyn+0.1 mph (+0.1%) | 94.6%qual 94.8% | ||
2 rule changes (STL: 2)1 cars added · 1 wording · STL ITA and ITS RX7, and ITS/ITA/ITB/ITC 1985+ models clarified to require tires per 9.1.4.2. · Spec MX5 in STL allows ACT clutch 0000-02-5004-G6, wheels 17x8, Toyo RR and RA1 235-40-17 tyres, or alternatives on 17x7 per rules.show
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| Virginia International Raceway Runoffs 20222022-09-24 | 2:05.474Danny Steyn · fastest of 24 · top 5 within 2.3s-1.729s (-1.36%) | 2:07.832Danny Steyn · fastest of 22 · top 5 within 1.9s+0.559s (+0.44%) | 131.7Trever Degioanni-3.2 mph (-2.3%) | 85.9%qual 95.1% | ||
5 rule changes (STL: 5)1 engine · 1 tyres & wheels · 1 weight · 2 wording · STU single throttle body weight reduction removed; minimum weights revised down to 2990 lbs at 3000cc from 3300 lbs. · STL and STU Improved Touring vehicles must now conform to section 9.1.4 Tires & Wheels. · STL/STU intake manifold and cylinder head porting clarified as free; intake and exhaust porting wording removed. · STL Mazda Renesis flat plate restrictor increases from 55mm to 60mm. · STL 79-85 RX7 12A allows emissions removal and jet correction on stock Nikki carb.show
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| Indianapolis Motor Speedway Runoffs 20212021-09-25 | 1:51.665Danny Steyn · fastest of 42 · top 5 within 1.7s-0.982s (-0.87%) | 2:02.711Joe Moser · fastest of 37 · top 5 within 3.2s+10.122s (+8.99%) | 131.8Max Gee | 101.6%qual 95.2% | ||
15 rule changes (STL: 15)3 engine · 2 aero · 2 cars added · 2 weight · 1 induction · 1 suspension & brakes · 2 wording · 2 other · STL Mazda Spec MX-5 removes redundant specification line referencing 2014 regulations. · STL Volkswagen 2.0L TFSI 1984 cc engine permitted without turbocharger, meeting all other STL specs. · STL Pontiac Solstice/Saturn Sky allowed 4 inch ride height. · STL Mazda B5 DOHC added to class; must meet all STL regulations. · STL Honda B16A (JDM) restrictor reduced from 54mm to 53mm. · ST oil coolers and filters now explicitly listed as addable or substitutable parts in vents and breathers section. · STL GM Ecotec LNF now permits any Ecotec engine family with 55mm flat plate restrictor. · ST 90-05 Mazda Miata allowed alternate front wheel hub Mazda Motorsports Development Part #0000-04-5HUB-S1. · ST cars may now relocate ABS actuation hardware and wiring anywhere in the engine compartment. · STL rear wing trailing edge may be mounted no further rearward than the center of the rearmost part approved bodywork. · STL alternate transmissions now allow OEM gear sets and input shaft modifications for fitment. · STL RWD strut-front cars lose 2.5% weight penalty, others lose 3% penalty for FWD parity. · STL Honda F20C drops 2% weight penalty, minimum weight reduced. · STL Honda B16/B17/B18C1 restrictor reduced to 53mm, B18C variants and Mazda MZR to 52mm. · ST aero devices and reference areas must include end plates, exclude fasteners under 1/2" protrusion.show
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| Road America Runoffs 20202020-10-02 | 2:31.420Danny Steyn · fastest of 33 · top 5 within 3.1s | 2:32.115Joe Moser · fastest of 30 · top 5 within 1.5s | 132.9Darin Treakle | 94.8%qual 95.3% | ||
11 rule changes (STL: 11)4 cars added · 4 engine · 3 wording · STL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis percentage additions, subtractions, and fixed pounds. · STL STU rear wing Gurney flap terminology clarified from wicker to Gurney flap in mounting and chord rules. · GT3 and STU add Borg-Warner EFR6258 turbocharger to approved turbo lists. · STL adds Mazda MX-5 Global Cup 16-18 at 2450 lbs minimum and 2019 at 2550 lbs minimum. · STL Mazda MX-5 Club 06-15 allowed header part number 0000-06-5407-NC. · STL Acura/Honda B18 and B18C engines: restrictor sizes swapped, B18C1 removed from allowed variants. · STL Honda B18 loses 53mm restrictor requirement; B18C1 added with 54mm restrictor, B18C1 removed from other variants. · STU GM Ecotech LNF now permitted without turbo, with LE5 head and intake manifold, meeting STL specs. · STL Mazda MZR restrictor reduced from 54 mm to 53 mm. · STL Mazda MZR restrictor reduces from 55 mm to 53 mm. · STL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL to notes.show
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| Virginia International Raceway Runoffs 20192019-10-05 | 2:07.203Danny Steyn · fastest of 36 · top 5 within 1.8s | 2:07.273Cliff Ira · fastest of 35 · top 5 within 1.4s | 134.8Cliff Ira | 93.8%qual 96.3% | ||
11 rule changes (STL: 11)3 cars added · 3 engine · 1 weight · 2 wording · 2 other · STL adds Mazda Spec MX-5 Challenge, 2000cc displacement, 2500 lb minimum weight, with mandatory Roush, Penske, Eibach, and other specified components. · STU allows alternate intake manifolds on case-by-case basis; stock throttle device and manifold otherwise required. · STL Acura/Honda B18 except C engine restrictor increased from 53mm to 54mm flat plate. · STL and STU ride height measurement clarified: lowest rocker panel point without driver, excluding pinch weld. · STL adds VW 1.8L R4 20VT 1781 cc, 1781 minimum weight, naturally aspirated only. · STL Mazda Renesis minimum weight reduced to 2700 lbs. · STL Mazda MX-5 Cup brake pad compound now open. · STL adds Acura/Honda B18C1 GSR with 1797cc displacement, 54mm flat plate restrictor required, porting outside 1" allowance prohibited. · STL Mazda 12 and 13B now permit port matching; porting ban removed. · STL B17 now requires 54mm flat plate restrictor; B18C Type R variants move to 54mm restrictor, weight chart baseline. · STL Mazda Miata removes maximum displacement limit; minimum weight corrected to unspecified figure.show
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| Sonoma Raceway Runoffs 20182018-10-10 | 1:49.138Danny Steyn · fastest of 19 · top 5 within 2.5s | 1:49.754Danny Steyn · fastest of 17 · top 5 within 2.5s | 103.2Craig McHaffie | 93.8%qual 97.0% | ||
| No rule changes on record between these events | ||||||
| Indianapolis Motor Speedway Runoffs 20172017-09-25 | 1:52.647Adam Roberts · fastest of 57 · top 5 within 0.8s | 1:52.589Eric Kutil · fastest of 50 · top 5 within 1.2s | 95.1%qual 95.9% | |||
| No rule changes on record between these events | ||||||
| Mid-Ohio Sports Car Course Runoffs 20162016-09-19 | 1:35.439John Schmitt · fastest of 34 · top 5 within 1.5s | 1:36.625Kevin Boehm · fastest of 31 · top 5 within 0.6s | 95.7%qual 95.8% | |||
| No rule changes on record between these events | ||||||
| Daytona International Speedway Runoffs 20152015-09-21 | 2:09.672Kevin Boehm · fastest of 37 · top 5 within 2.5s | 2:10.269Kevin Boehm · fastest of 37 · top 5 within 2.1s | 94.7%qual 95.2% | |||
By track
| Track | Events | Typical % of the field | Best | Latest |
|---|---|---|---|---|
| Road America | 4 | 94.8% | 94.8%Runoffs 2026 | 94.8%Runoffs 2026 |
| Virginia International Raceway | 3 | 93.8% | 85.9%Runoffs 2022 | 94.6%Runoffs 2023 |
| Indianapolis Motor Speedway | 2 | 95.1% | 95.1%Runoffs 2017 | 101.6%Runoffs 2021 |
| Daytona International Speedway | 1 | 94.7% | 94.7%Runoffs 2015 | 94.7%Runoffs 2015 |
| Mid-Ohio Sports Car Course | 1 | 95.7% | 95.7%Runoffs 2016 | 95.7%Runoffs 2016 |
| Sonoma Raceway | 1 | 93.8% | 93.8%Runoffs 2018 | 93.8%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.