Are you talking about the Formula World Championship? My guy won them all pretty easily, well, except for the 6th. I haven't raced the 6th yet, I stopped him after 5 because I have to go to bed soon and he had already clinched.
My guy is level 22 and the race is 23, so I don't think that matters. I just made two new players so I'd have 4, and threw all 4 of them into the first endurance race. Hopefully they all get good experience, doubt the 2nd two new guys will do all that well, but I gave them a car with 200 more HP than the competition, and they'll have a huge lead by the time they start driving, and it's 4WD, so maybe they won't do too terribly.
I'll see in the morning how they did.