Autocross Tire Guide: From All-Seasons to R-Comps
No single upgrade will improve your autocross times more than tires. Not suspension. Not alignment. Not a limited-slip differential. The patch of rubber between your car and the pavement determines the absolute limit of what your car can do in a corner, and in autocross — where the entire event is corners — tires are everything.
The good news is that SCCA classing rules are designed so that the cars most people own can be competitive on street-legal tires. You don't need R-compounds to be fast in Street class. Understanding the tire rules for your class, picking the right tire, and learning to drive on it consistently will get you further than anything else you can bolt on.
Why Tires Matter More Than Almost Any Other Upgrade
Autocross is a traction-limited sport at virtually every skill level up through advanced. In a 60–90 second course with 30–50 transitions, your tires are constantly at or near their grip limit. Every corner entry, every rotation, every acceleration point depends on traction — and traction is a function of the tire compound, the contact patch area, and how well the tire is loaded through suspension geometry.
A stock Miata on Bridgestone RE71RS tires will absolutely demolish the same Miata on all-season tires driven by an equally skilled driver. The grip difference between a quality all-season and a 200TW performance tire is enormous — we're talking 20–30% more lateral acceleration capacity. That's not a marginal improvement. That's a completely different car.
If you're building an autocross car and have a limited budget, spend it on tires first. A $700 set of RE71RS or RT660 tires will give you more improvement per dollar than any suspension modification, any alignment, or any power upgrade. This is not an opinion — it's physics.
How to Read UTQG Ratings
UTQG stands for Uniform Tire Quality Grading, a federal system the NHTSA requires on all passenger tires sold in the United States. It appears as three numbers/letters on the tire sidewall, like: 200 A A
- Treadwear (first number): A relative rating of expected tread life compared to a reference tire (rated 100). A 200TW tire should last roughly twice as long as the reference. A 100TW tire lasts half as long. For competition purposes, this number is also a rough proxy for grip — lower TW numbers generally mean stickier compounds. Note that UTQG testing is not standardized across manufacturers, so a Bridgestone 200TW and a Yokohama 200TW are not directly comparable in terms of actual life.
- Traction (letter grade A, B, C): Wet stopping performance in a straight line on specified test surfaces. A is best. This is not a measure of lateral grip or cornering traction — don't use it to compare tires for autocross purposes.
- Temperature (letter grade A, B, C): Heat resistance at high sustained speeds. A is best. Again, this measures straight-line thermal stability, not autocross performance.
For SCCA Solo competition, the treadwear number is what matters. Street and Street Touring classes require a minimum 200TW tire.
Tire Categories for Autocross
Autocross tires fall into four rough categories, listed from most street-friendly to most track-focused:
All-Season / UHP All-Season
Factory tires on most cars. Typically 400–600TW. Acceptable for your first few events while you learn the sport. Limiting factor quickly becomes the tire's inability to build consistent heat and grip. Not competitive in any serious class. Examples: Michelin CrossClimate2, Continental ExtremeContact DWS06+.
200TW Extreme Performance Summer (200TW)
The competitive class for SCCA Street and Street Touring. These tires have a UTQG treadwear rating of exactly or just above 200, making them eligible for all Street-class competition while remaining street-legal. This is the most important tier for the vast majority of SCCA Solo competitors. See our 200TW tire comparison for in-depth analysis of the top picks.
Max-Performance Non-200TW Summer
Tires like the Michelin Pilot Sport Cup 2 and the Continental ExtremeContact Force that have treadwear ratings below 200TW. These are legal for street use but not eligible for SCCA Street/Street Touring classes due to the 200TW rule. They fall into Prepared or Modified class for SCCA purposes, or are run in open class events. Grip is significantly higher than 200TW tires, but tread life is very short.
R-Compound (DOT Race Tires)
Tires like the Hoosier A7 and Toyo Proxes RR. These carry a DOT street-legal rating but are purpose-built race tires with very low TW ratings (typically 40–100). Allowed in SCCA Prepared and Modified classes, and in some Time Trial categories. Not legal for Street or Street Touring. Dramatically faster than 200TW tires, but expensive, wear quickly, and very heat-sensitive.
SCCA Solo Tire Rules by Class
| SCCA Class | Min Treadwear | R-Comps? | Notes |
|---|---|---|---|
| Street (SS, AS, BS, CS, DS, ES, FS, GS, HS) | 200TW | No | Must meet 200TW UTQG; some regions require Tire Rack approved list |
| Street Touring (STR, STX, STH, STS, STF) | 200TW | No | Same 200TW rule; more car mod freedom |
| Street Modified (SM, SMF) | None | Yes | R-comps allowed; very open class |
| Prepared (CP, DP, EP, FP, HP) | None | Yes | R-comps allowed; class-specific size limits apply |
| Modified (AM, BM, CM, DM, EM, FM) | None | Yes | Very open rules; R-comps standard |
| CAM (CAM-C, CAM-S, CAM-T) | 200TW | No | Same 200TW rule as Street; verify current CAM rules |
| CAMC (CAM Challenge) | None | Yes | Check current rulebook |
SCCA Solo rules are updated annually. Class structures and tire eligibility rules do change. Always verify your class rules with the current SCCA Solo Rules document before purchasing tires for a competition event. The summary above is accurate as of the 2025-2026 season but may not reflect future changes.
The Top 200TW Tires for 2026
Three tires have dominated competitive SCCA Street and Street Touring class for years: the Bridgestone RE71RS, the Yokohama ADVAN A052, and the Falken Azenis RT660. As of 2026, two of the three have been updated (the RT660 became the RT660+ in 2025; the RE71RS is being replaced by the RE71RZ), and a strong new contender — the Hoosier TrackAttack Pro — has entered the category with impressive test results. More on that below.
The short version: the A052 has the highest peak single-lap grip in cool conditions, the RT660+ has the best heat tolerance and tread life, and the RE71RS/RZ is the most consistent all-conditions choice. See our dedicated 200TW tire comparison for more detail on how they stack up.
The Hoosier TrackAttack Pro arrived in late 2024 and topped both the 2024 and 2025 Grassroots Motorsports comparative tests — beating the RE71RS, A052, and Michelin Cup 2 R in back-to-back testing. Lighter construction, excellent heat tolerance, and fast warm-up. One critical catch: it has only 5/32" tread depth, which does not meet SCCA Solo's 7/32" minimum for street tires. The TrackAttack Pro is not eligible for SCCA Street or Street Touring class autocross. It is legal for NASA HPDE, time trials, and autocross organizations that don't enforce the 7/32" rule — check with your event organizer before buying.
Which 200TW Tire for Your Situation
Community consensus is surprisingly clear on this, so here it is without the hedging:
| Your Situation | Best Pick | Why |
|---|---|---|
| First 200TW tire | RT660+ | More forgiving limit, no heat-management stress, best cost-per-event |
| Cool morning events (<65°F) | A052 | Fastest warm-up, peak grip advantage is largest in cool temps |
| Hot summer events (85°F+) | RT660+ | Heat tolerant — maintains grip where the A052 fades |
| Wet or mixed conditions | RE71RS / RE71RZ | Best wet performance of the mainstream 200TW options |
| Frequent competitor (10+ events/yr) | RT660+ | 4–5 season tread life vs 2–3 for A052; best cost over time |
| Chasing outright lap times (cool day) | A052 | 0.5–1.0 sec per lap advantage over RT660+ on fresh rubber in cool conditions |
| HPDE / non-SCCA track use | TrackAttack Pro | Fastest in current testing, excellent heat tolerance — no SCCA eligibility concern |
If you run the A052 in hot conditions and have time between runs, pour ice water directly over the tires after each run. This is a legitimate technique that competitive autocross drivers use regularly — it drops the carcass temp back into the A052's operating window before the next run. Without it, back-to-back hot runs on the A052 cost you meaningful grip. With it, the A052 remains competitive even on summer days.
What About Non-200TW Performance Tires?
Several high-performance street tires fall below the 200TW threshold and are therefore not eligible for SCCA Street or Street Touring classes. The most notable examples are:
- Michelin Pilot Sport Cup 2 / Cup 2 R: Among the fastest street-legal tires made. Legal for Prepared and Modified classes. Not legal for Street/ST. Exceptional grip, very short life, very expensive.
- Continental ExtremeContact Force: Aggressive compound, below 200TW in some sizes. Check specific size UTQG ratings before purchasing for competition.
- Toyo Proxes R888R: Borderline 200TW — some sizes are rated above 200, some below. Excellent grip and a well-regarded R-compound-adjacent tire. Verify your specific size's UTQG before entering Street class.
R-Compound Tires
R-compounds (R-comps) are DOT street-legal tires built with race-car compounds. They offer dramatically more grip than 200TW tires — often 25–40% more lateral acceleration — but are not class-legal for Street or Street Touring competition. If you're in Street or ST class, skip this section.
Hoosier A7 / A8
The Hoosier A7 has been the dominant SCCA Prepared and Modified autocross tire for years. In Hoosier's naming convention, the A-series (A7, A8) uses a softer compound designed to reach full grip quickly at lower operating temperatures — ideal for autocross where you get 60–90 second runs with long waits between. The R-series (R7, R8) uses a harder compound that needs sustained heat to come in — better suited for road course sessions of 20+ minutes where the tire can reach and hold its operating window. If you're doing autocross, you want the A-series. If you're doing HPDE or circuit racing, the R-series.
Hoosier launched the A8 as the A7's replacement in late 2025, but initial testing was disappointing: the A8 failed to match the A7's mid-corner grip in Grassroots Motorsports' first head-to-head test. The R8 showed more promise in the same test — consistent and smooth once up to temperature. If you can still find A7 stock, many competitive drivers prefer it over the A8.
A7 caveats worth knowing: it ages out before it wears out on light cars — the compound degrades in storage and loses compliance after 3+ years regardless of use. It's also not rated for near-freezing temperatures. High cost ($300+/tire) and short competitive life make the cost-per-event math unfavorable unless you're running at a national competition level.
Toyo Proxes R (replaces Proxes RR)
The Toyo Proxes R launched in 2024 as a significant upgrade over the old Proxes RR. Community consensus: the Proxes R is competitive with the Hoosier R7 (harder compound) for track use, and NASA adopted it as the 2025 spec tire for Spec3 classes. The old RR was famous for durability but was consistently 1.5–3.5 seconds per lap slower than the Hoosier A7 — the new Proxes R closes that gap substantially. For drivers who want R-comp grip without Hoosier pricing, the Proxes R is the current value pick.
Yokohama Advan A055
Yokohama's R-compound option, positioned as a Hoosier A7 competitor for SCCA Prepared/Modified. In Yokohama's own track test, the A055 ran 1:24.4 fastest lap versus 1:26.0 for the A052 — a meaningful gap. The A055 reaches full operating temperature in about 1.5 laps and has edgier breakaway characteristics than the A7, particularly at the rear. Worth considering if you're buying a full set for Prepared class and want an alternative to Hoosier.