Maybe. There's alot going on right in front of the start. Depending on how fast people get through the first part of the course, I can picture one car finishing about the time the car behind enters the sweeper coming back across the start, and another car staged waiting to start. That puts three cars too close together.

Were I doing it, I'd back the start line up to get at least 100 ft separation between the sweeper and the start line (more if there's room), and eliminate the loop on the right side of the course near the end -- just send 'em out there and bring them back across to the finish without the additional loop. That way, you can start the second car after the first has cleared the hard left at the end of the sweeper (headed towards the right side of the picture); the first car will finish before the second gets back, and the guy stationary at the start line isn't worried about either one spinning into his nose.