Bonus Cars:
Start a new race and select the "Begin Career" option.
At the "Register" screen, enter "Go Bears!" for Stock
cars, or "Go Bruins!" for Formula One Cars.
Change Car Color:
While racing, pause the game and go to the Race Strategy
screen. From here, press and hold L1 + L2 + R1 + R2 + X
+ Circle + Select.
Master Options:
While racing, pause the game and go to Race Standings.
Now press Circle + X (you might have to do it once or
twice.) An option screen will appear which allows you to
change the speed of your opponent, gas mileage, tire
wear, and more!