This is pretty cool. I tried messing up some of the JavaScript variables (increasing acceleration, turning speed), and it looks like they do some sort of server-side validation on your race results. The Ajax POST request includes your score, the path you took, and the road that the game generated (and didn't accept my sub-30s score).

I set the game parameters to generate a straight course (set curvy, mountainy to 0) and got 32.94 seconds, so I'm not sure how some people are getting ~33 seconds honestly.