Group CN
Group CN is a category of motorsport, introduced by the FIA in the early nineties for sports car racing. Group CN cars are mainly seen in hillclimbing championships or sports racing series. Group CM is a non-FIA class which is closely related to Group CN.
Major racing series
Group CN rules are applied to a variety of championships. Many championships alter the rules in their own way like the Radical European Masters and V de V championships.Radical European Masters
The Radical European Masters is a spec racing series in Europe. It features the Radical SR8, Radical RXC Spyder and Radical SR3, each in their own class.V de V
The French-based V de V organisation features two FFSA Group CN based classes. The endurance championship is open for any chassis and engine within the regulations. The V de V organisation also features the Funyo Challenge open to Peugeot powered Funyo 4 or Funyo 5.National championships
A Group CN racing class exists in many countries, many of which utilize radicals. Examples are the Radical UK Cup which features the Radical SR3 and the Open España Prototipos.GT & Prototype Challenge
Ran as part of the Benelux-based Supercar Challenge, the GT & Prototype Challenge allows Group CN classification cars to compete; current competitors include the Radical SR3 and Norma M20 FC.FIA Group CN technical regulations
| Engine | Maximum of 6 cylinders and 3000cc, homologated by the FIA in Group N. |
| Drivetrain | Free, with a maximum of 6 forward ratios. Reverse gear is compulsory. |
| Maximum dimensions | Length: 4800mm |
| Maximum dimensions | Width: 2000mm |
| Maximum dimensions | Height: 1030mm |
| Maximum dimensions | Front plus rear overhangs not to exceed 80% of the wheelbase. |
| Maximum dimensions | Difference between front and rear overhangs not to exceed 15% of the wheelbase. |
| Bodywork | Open or closed cockpit |
| Rear wing | Maximum of 2 elements, which must fit within a 150x400mm cross section. Maximum span of 1800mm |
| Minimum weight | Related to engine capacity |
| Minimum weight | Up to 1000cc: 475 kg |
| Minimum weight | 1000cc - 1300cc: 495 kg |
| Minimum weight | 1300cc - 1600cc: 515 kg |
| Minimum weight | 1600cc - 2000cc: 535 kg |
| Minimum weight | 2000cc - 2500cc: 575 kg |
| Minimum weight | 2500cc - 3000cc: 625 kg |