3 Hour Challenge 

As many laps in 3 hours. 

6 Hour Challenge 

As many laps in 6 hours. 

12 Hour Challenge 

As many laps in 12 hours.

The Ultimate Test:

24 Hour Challenge 

As many laps in 24 hours. 

Or just come for a lap..or two

Starting at any of the 4 start times over the 24 hours (need to also attend race briefing for that start time)