All cars:
At the main menu, press L1, L2, R1, R2, Circle, Square.

All tracks:
At the main menu, press L1, R1, R2, Square, Circle.

Unlock next cup:
At the main menu, press L1, R1, R2, L2. Enter this code repeatedly to unlock all seven championships.

Quick start:
Press X as soon as "Go" appears during the pre-race countdown.