Vehicle Classification Guide

  • DRIVERS ARE RESPONSIBILE FOR VEHICLE CLASSIFICATION
    • Any obvious mis-classification can be corrected at the discretion of a member of the Competition Committee or the Event Chairman.
    • The Autocross Club of Central Oregon follows the car classification rules as outlined in the current SCCA Solo Rulebook and subsequent updates.
    • The following are highlights of allowances for a particular category. If the rulebook doesn’t say you can do a particular modification, you can’t do it.
  • STREET CATERGORY
    • Cars having little if any modifications.
    • Aftermarket fluids, filters, other maintenance items are permitted.
    • Tires must be DOT legal, including R-tires.
    • Shocks can be changed but must retain the OEM geometry and dimensions.
    • Wheels must be the same size as stock +/- 1″ circumference but any size tire that fits on the wheel is permitted.
    • Only one sway bar may be changed or modified.
    • Classes are listed as: AS, BS, CS, DS, ES, FS, GS, HS.
  • STREET TOURING CATEGORY
    • Sport compact cars with four seats, common suspension, engine, and appearance modifications competing on true street tires with a minimum tread wear rating of 140.
    • Modifications relate to basic bolt on that still meet the car’s emissions standards.
    • Suspension allowances are similar to Street Prepared.
    • STS has a maximum engine displacement of 3.1 liters and some small displacement turbo cars.
    • STX has a maximum engine displacement of 5.0 liters or 2.0 liter turbo or supercharged.
    • Classes are listed as AST, BST, CST, DST, EST, GST, SST, SS.
  • STREET PREPARED CATEGORY
    • Allowances in excess of Stock and Street Touring. Full interiors but race seats are permitted.
    • Engine intake and exhaust are free but no modifications to turbo or supercharger systems.
    • Emissions control systems may be removed. Coil-over suspensions with adjustable perches and camber plates, etc. permitted.
    • Classes are listed as: ASP, BSP, CSP, DSP, ESP, FSP, SSP.
  • STREET MODIFIED
    • Cars equipped with drive train and suspension modifications that are beyond those allowed in the Street Prepared Category.
    • Unrestricted brake and suspension components but with original pickup points. Engine swaps within the same model line and turbo or supercharger may be added.
    • Non-Stock hoods and fenders are permitted.
    • Classes are listed as SSM, SM, SMF.
  • PREPARED
    • Prepared cars are defined as those having extensive mechanical and weight saving modifications and racing slicks.
    • The basic body and engine configuration on Prepared cars remains as delivered from the factory.
    • Classes are listed as: BP, CP, DP, EP, FP, XP.
  • MODIFIED
    • Modified cars are defined as those having very extensive mechanical and weight saving modifications and racing slicks.
    • The modified classes contain specials, formula cars, and engine swaps.
    • Classes are listed as: AM, BM, CM, DM, EM, FM.
  • CLASSIC AMERICAN MUSCLE
    • The purpose of CAM is to attract automobile enthusiasts who are currently interested and/or participating in autocross events for muscle cars and vintage vehicles manufactured in North America by GM, Ford, Chrysler and AMC.
    • Vehicle must be either a domestic automobile or truck (pick-up or SUV) of front-engine/rear-wheel-drive (FE/RWD) configuration.
    • Classes are listed as: CAM-C, CAM-T, CAM-S.
  • XTREME STREET CATEGORY
    • The purpose of this Category is to attract automobile enthusiasts interested in autocross events with popular street vehicles using minimal rules that allow for creative modifications with limited restrictions.
    • Classes are listed as: XA, XB, XU.
  • HERITAGE CLASSIC CLASS
    • Vehicle must be from model year 1974 or older and not produced by a United States based manufacturer. Models newer than 1974, but of the same generation as the 1974 model, are allowed. EXAMPLE: a 1978 MGB would be eligible.
    • There are two classes; Heritage Classic Street (HCS) and Heritage Classic Race (HCR). HCS is for street legal vehicles competing on street tires with common enthusiast modifications. HCR is for race prepared vehicles competing on any tires with modifications similar to those common “back in the day”.
  • CLUB SPEC
  • Mustang
    • The Mustang for Club Spec is the fifth generation with the 4.6L V-8. Known best by the chassis code S197, these cars were sold in the US from 2005 until 2009
    • Classes are listed as: CSM
  • MIATA
    • The MX-5 for Club Spec is the third generation, known best by the chassis code NC. These cars were sold in the US from 2006 until 2015.
    • Classes are listed as: CSX.
  • KARTS
    • This category is an outlet for members interested in running karts at Autocross events.
    • Category Values Preparation allowances in line with national karting organizations, to allow easy migration between Solo and other karting events.
  • Electrical Vehicle Experimental
    • The purpose of EVX is to provide an alternative class specifically targeted towards production electric powered vehicles.
    • This ruleset draws from Street and Street Touring with the intention of choosing common-sense allowances to balance streetability and autocross preparation.
    • Wider wheels/tires will diminish range slightly, but still work well for street use while improving autocross performance.
    • Classes are listed as: EVX
  • LADIES CLASSES
    • Women are free to compete in the Open class in which their car is legal. However, ladies’ classes will be established in the following manner: Multiple Classes – A complete set of parallel classes using the same preparation and scoring system as in the Open classes.
  • Compare Modifications, PAX Handicap List