The P3 class is reserved especially for P3 type-Prototype cars of both the first and second generation.
The P3 categroy is used in many prototype based championships around the world.
The current version of P3 prototypes is running with a unified Nissan VK56 V8 Engine with 5,6 liters capacity, producing up to 460 HP at a weight of 900 Kg.
The FIA CN category is reserved for cars that are in line with FIA ISC Appendix J Art. 259 These sports cars are designed to run at low weight and high power. Within the series, the class is limited to an engine capacity of 2L or 1,6L Supercharged respectively