Group CN is a category of vehicles used inmotorsport, introduced by theFIA in 1993 forsports car racing.[citation needed] Group CN cars are mainly used inhillclimbing championships or sports racing series.Group CM is a non-FIA class which is closely related to Group CN.
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.
The Radical European Masters is aspec racing series in Europe. It features theRadical SR8,Radical RXC Spyder andRadical SR3, each in their own class.
The French-based V de V organisation features twoFFSA Group CN based classes. The endurance championship is open for any chassis and engine within the regulations. The V de V organisation also features theFunyo Challenge open toPeugeot poweredFunyo 4 or Funyo 5.
From2022, the Indian Racing League has usedWolf GB08 "Thunder" models built to Group CN specification.[1]
A Group CN racing class exists in many countries, many of which utilize radicals. Examples are theRadical UK Cup which features the Radical SR3 and theOpen España Prototipos.
Ran as part of the Benelux-basedSupercar Challenge, the GT & Prototype Challenge allows Group CN classification cars to compete; current competitors include theRadical SR3 andNorma M20 FC.
| Engine | Maximum of 8 cylinders and 3000cc, homologated by the FIA inGroup N. |
| Drivetrain | Free, with a maximum of 6 forward ratios. Reverse gear is compulsory. |
| Maximum dimensions | Length: 4800mm |
| Width: 2000mm | |
| Height: 1030mm | |
| Front plus rear overhangs not to exceed 80% of the wheelbase. | |
| 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 (without driver) | Related to engine capacity |
| Up to 1000cc: 475 kg | |
| 1000cc - 1300cc: 495 kg | |
| 1300cc - 1600cc: 515 kg | |
| 1600cc - 2000cc: 535 kg | |
| 2000cc - 2500cc: 575 kg | |
| 2500cc - 3000cc: 625 kg |