- Novice (N): a perfect place for drivers new to the sport of autocross. Drivers may run Novice for their first year. Class is scored on the PAX* Index
- Pro (P): You’ll find the fastest local, regional, and (sometimes) national level drivers competing in this PAX* class.
- Street Tire Modified (STM): If you have a street-legal car on street tires (minimum treadwear rating of 200), you can run STM. This class is intended to serve as a catch-all for cars whose mods put them into an uncompetitive class. It’s scored on Raw time only.
*PAX classes allow cars from different classes to compete together using a handicapping system. They are scored based on a theoretical time obtained by multiplying a driver’s actual time by their car’s PAX index. This way a Civic can (theoretically) compete with a Corvette.
Driver’s choosing to run a PAX class must also properly determine their base class. For example, someone wanting to compete in the Novice class with a BS car would need to register “Novice” as their PAX class and “BS” as their base class. On the sides of their car they should display “NBS##”.