Loads of Money
Start a new career and pick your driver, then enter the following code: L1, L1, L1, L1, L1, L2, L2, L2, L2, L2, R1, R1, R1, R1, R1, R2, R2, R2, R2, R2, L1+R1+L2+R2.
Pause the game and press L2, R2, L1, R1, L2+R2, L1+R1. Enter the same code to turn it off.
Pause the game and press L1+R1, L2+R2, L1+L2, R1+R2. Enter the code again to turn it off.
Unlock Fast Oval Race
Press L1, L2, L1, R1, L1, R2, L1+R1, L2+R2 at the title screen.