Best Tires for SCCA Street Class
In SCCA Solo Street class, the rules box is tight. Stock or stock-equivalent suspension, limited to OEM wheel sizes, and a 200 treadwear minimum on tires. Within those constraints, tire choice is the single biggest performance variable between otherwise equal cars and drivers. Getting tires right can be worth several tenths per run — more than most legal suspension tuning.
The SCCA Street Class Tire Rule
Street class requires tires with a UTQG treadwear rating of 200 or higher. The tire must be commercially available (no custom compounds). The SCCA publishes a Solo Rules document annually — always verify against the current version, as specific sub-class rules occasionally change.
Key point: the treadwear number on the sidewall is self-reported by the manufacturer using the UTQG standardized test. A 200TW tire from one manufacturer may feel dramatically different from a 200TW from another. The number doesn't represent grip — it represents relative wear rate under standardized conditions.
The Traction rating (A, B, C) and Temperature rating on a tire are separate from Treadwear. A 200TW tire can still have Traction A and Temperature A ratings. The Yokohama A052, for example, is 200TW but is one of the grippiest street-legal tires available.
Sizing in Street Class
Street class limits you to OEM wheel width (or close to it) and generally requires tires that fit within factory fender clearance. The class rules specify allowable tire width — check the rules for your specific class letter.
In practice: run the widest tire that fits within the class rules and your wheel. Wider tires generally provide more grip in autocross, up to the limit where wheel width becomes a mismatch (a 255 on a 7" wheel is worse than a 245 on the same wheel).
Best Tires for Street Class
Common Street Class Cars and Typical Sizes
| Car | Class | Typical Competitive Size | Common Tire |
|---|---|---|---|
| Mazda MX-5 ND | GS | 205/45R17 | RE71RS / RT660 |
| Toyota GR86 / Subaru BRZ | GS | 225/45R17 or 235/40R18 | RT660 / RE71RS |
| Honda Civic Type R FK8 | GS | 235/35R19 | A052 / RT660 |
| Subaru WRX (VA) | GS | 245/40R18 | RE71RS / RT660 |
| VW Golf GTI (Mk8) | GS | 225/40R18 | A052 / RT660 |
| Ford Mustang GT S550 | GS / SST | 275/40R19 | RE71RS |
Wheel Width Matters
The same tire behaves differently depending on the wheel it's mounted on. A wider wheel stretches the tire sidewall slightly, reducing sidewall flex and improving responsiveness but reducing the tire's ability to absorb surface imperfections. Most competitive autocross drivers run their 200TW tires on wheels 1/2" to 1" wider than the factory spec, within Street class rules.