What class would my car run in

SCCA Autocross has six major competition categories which are then broken down in classes of like cars.

The major categories are as follows:

This class is comprised of 9 classes, SS and from AS to HS, divided according to performance potential and car type, covering everything from Corvettes to Corollas. Cars are essentially as they rolled off the showroom floor with some generally, minor modifications allowed to expendable parts as defined in the Solo Rule Book and must run on a DOT legal street tires with a treadwear of 200 or higher. These are truly street tires and not the DOT race tires you will find in the other categories. Most of the cars in this category are driven to the event on these tires.

Made up of 6 national classes (STU, STR, STX, STS, STF & SST) and our local STO class, this category is intended for the person “off the street” who had performed common hot-rodding bolt on improvements. Most of these cars are used on the street as daily drivers (thus the name for the category) and they must run on DOT legal Street tires with a treadwear rating of 200 or higher. These are truly street tires and not the DOT race tires you will find in the other categories. Most of the cars in this category are driven to the event on these tires.

This is a category which allows a certain amount of “hot-rodding” to the cars, such as wheel size & width, induction and suspension changes. This category has 7 classes, SSP, ASP, BSP, CSP, DSP, ESP, and FSP. There is a noticeable increase in performance over the Street and Street Touring classes. While some of these cars are still used on the street, many become purpose built race cars. Cars in these classes use DOT legal race tires.
Like the Street Prepared category, this is a category which allows a certain amount of “hot-rodding” to the cars, however it also allows engine swaps, adding forced induction, and replacement body panels. This category has 3 classes, SSM, SM, and SMF. While some of these cars are still used on the street, many become purpose built race cars. Cars in these classes also use DOT legal race tires.

This category is not intended for the street driven car, though a few competitors do drive their Prepared cars on the street. These cars have their interiors removed, one bucket seat, a roll cage, and extensive engine & suspension modifications. This class is comprised of 5 classes, from CP to FP plus XP, and they all run on purpose built racing slicks. This category often has SCCA Production and GT class cars in it and once again there is a noticeable increase in performance over the Street Prepared classes.

This is the class where you will find Formula Fords, F440’s, Sports racers, karts and exotic production based home built cars. This class is comprised of 7 classes, from AM to FM and KM. All of these bad boys are brought to the event on trailers.

Autocross Rules/Classes

The SCCA annually publishes the Autocross Rules to classify a full range of imported and domestic sports cars, sedans, and purpose-built race cars, as well as to layout the basic rules behind Autocross competition. The Autocross Car Classifications are provided so that you may determine what types of cars are typically competing in Autocross, although there is a class for just about any vehicle. The organizers of local events are also allowed enough leeway to add classes to suit their particular requirements.

National Rules/Classes

  • Click here to view a PDF of the current Solo Handbook from the SCCA site.
  • Click here for all PAX numbers.

Regional Rules/Classes

  • Click here to view a PDF of the Houston Region SCCA 2018 Solo Operations Manual.
  • Click here to view a PDF of the Houston Solo Safety Rules.
  • Click here to view a PDF of the 2016 STO Class Rules, still in effect for 2018.  The 2018 PAX for STO is 0.833.
  • Click here to view a PDF of the Clarification of the 2016 Class STO Rules.
  • Click here to view a PDF of the 2018 X Class Rules.
  • Click here to view a PDF of the 2018 Novice Class Rules.