A minimum of two cars per team, a maximum of four. (you can have two cars with up to four drivers or any other combination) No single car can do more than 2.5 hours. Each car must do a min of 30 mins unless there is a serious failure. 1 hour for qualifying giving enough track time for four car teams.
Each team has its own race number, each car carries the number (plus a letter A, B, C or D). As one car comes into the pit lane a team car pulls out of the garage and follows it. One comes into the paddock whilst the other goes onto the track.
Experienced handicaping ensures a close race. The handicap gives every team a chance to win with the race becoming more competitive on track towards the flag.