Enter the Cheats at the press start screen, and if you do it right you
 will hear a noise.
 
 BONUS CARS:
 up, left, right, X, circle, Square
 
 HIDDEN TRACK:
 X, up, triangle, down, R1, L1
 
 REVERSE CHAMPIONSHIP:
 left, triangle, R1, circle, L1, down
 
 SUPER CHAMPIONSHIP:
 right, Square, left, circle, up, X