I've read about this one in the past. Isn't this the race where you have to specify your average speed for the run and then get as close to that as possible? That's the challenge. You have to stay within a 10 MPH window the entire time as well. So, if you dial in at 100 MPH and touch 112 MPH - you're done. And you have to stay between 90 and 110 for the 2 hour run - curves and all. Is that the basic concept?