Out of the box and stolen from the Brits...
A relay enduro of TBD determined length.
1. A team consists of 2 or more drivers and cars.
2. Only one car from a team may be on course at anyone time. When a team's on-course car passes the team's pit stall, the car running the next leg may depart the team's pit stall and enter the course. If a team's car becomes disabled on course, the next leg is released when <insert rule here>.
3. No work may be performed on a car in the pits.
4. The number of laps run by a particular car is weighted by the following rule:
Lap record for class/fastest lap record among entered cars, rounded to 2 digits.
4A. Laps run under a full-course caution do not count towards the lap count.
4B. For example, in a Summit Point field consisting of GT1, ITR, ITA and ITB cars, each lap completed by a GT1 car would count as 1 lap completed. Each lap by an ITR car would count as 1.16 laps completed. Each lap by an ITA car would count as 1.19 laps completed. Each lap by an ITB car would count as 1.26 laps completed.
5. Victory is determined by the greatest number of weighted laps completed.
Want to run a 2-hour stint? Go ahead. Want to run a 40 minute race? Go ahead. It all works out in the end.