Bonus tracks
Goto practice mode, select a track, car, and transmission. When the race begins, turn you car around and drive in the opposite direction. When you pass the first check point, you will be placed in first place. Then, the other cars will eventually turn and follow. Three new tracks will now be accessable.
Turn off Time Limits
On the starting screen, hold R1 + Circle + R2 then you should hear an engine sound.