Unlock All Trophies/Cars:
Goto the Game Progress screen and enter the following:
L1, R1, Left, Right, Left, Right, Up, Down, Up, Down, X, X+Select You should now hilight a square to access the car/trophy.

Speed Up:
Enter the following as a name:
LDN

Unlock Alternate Tracks:
First, enter a driver name below, and then start and quit a race. Next, start another new race and choose a car in Time Trial mode. Finally, select the Corsica and a track and an alternate track will be available.

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