I like this, but here’s an idea.
How about you charge less for the overall track day for those who just want to mess around, which would be 5hrs of track time. Then for the 3 hrs of competition, you charge $25-30 per person to whoever wants to compete. This allows more time for those who TRULY want to compete and won’t have the few guys who just want to mess around because its included in the full day.
Just my input 