Stock Category has nine classes covering most of the “daily driver” cars coveted by auto enthusiasts with only nominal modifications, such as alternate shocks, front sway bars, and mufflers.

Street Touring Category has five classes for selected enthusiast cars that have popular “bolt-on” modifications such as alternate springs, exhaust systems, limited larger wheels, and cold air intake, while maintaining “streetability” with emissions equipment and street performance tires.

Street Prepared Category has six classes for most enthusiast cars that have been modified beyond Street Touring with alternate fuel and ignition systems, as well as unlimited wheels, competition street tires, fender flares, and more aggressive suspension components.

Street Modified Category has three classes for enthusiast sports cars, coupes/sedans, and front wheel drive coupes/sedans that have been modified beyond Street Prepared with components such as alternate engines, transmissions, and suspensions, as well as unlimited forced induction, which makes Street Mod the unquestioned ultimate “street” classes in SCCA Solo.