Under 1000cc unmodified Minis, Citroen AX and Fiat Cinquecento. No modifications are allowed other than those required by the regulations for safety.
Up to 1300cc, limited modification vehicles. Limited engine and suspension modifications are permitted. All engines must breathe through a 32mm inlet restrictor. Cars can be either front or rear wheel drive.
Over 1351cc, front engined, rear wheel drive, modified saloons. Any two-valve per cylinder engine is permitted in any bodyshell. Rear wheel drive conversions of front drive cars are permitted.
Up to 1130cc modified vehicles. The only restrictions in this class are that the engine must remain in the original position and must be of a type originally sold in that type of car. Ultra lightweight Minis are the most competitive cars.
1131cc-1420cc modified vehicles. Any engine may be used in any position in the bodyshell.
Over 1421cc, front wheel drive, modified vehicles.Any modifications are allowed within a front-wheel drive configuration.
Over 1421cc, rear wheel drive, modified vehicles. The unlimited saloon class. Mid-engined cars based on small saloons, powered by anything from 16v four cylinder engines through V6s and V8s (often with forced induction) to twin motorcycle engines.
Up to 1420cc (1350cc for motorcycle engines) specials. The smallest of the open-wheeled single seaters. Based on home built or proprietary chassis and powered predominately by motorcycle engines.
1421cc-2065cc specials.The mid-range specials class no longer permits the use of motorcycle engines. Vauxhall's 16v engine and Ford's Zetec are the most popular, mounted transversely.
Over 2065cc specials. The unlimited specials class, powered by anything from 16v four cylinder engines through V6s and V8s (often with forced induction) to twin motorcycle engines.
Classes 1&2 race together, duly handicapped.
Classes 4,5&6 race together, duly handicapped.
Classes 3&7 race together, duly handicapped.
Classes 8,9&10 race together, duly handicapped.
Age 12-16 years. Can only race class 1 Minis or the recently introduced junior special, which is powered by a 1200 Vauxhall Corsa engine and gearbox.
