To enter these codes press UP, DOWN, LEFT, RIGHT at the main menu. This will take you to a cheat console where you can enter these codes:
Police warning instead of ticket: Enter LETMEGO as a code. The first three times you are pulled over the cop will only give you a warning.
Police car: GOTPOPO
Mazda RX-8 in arcade mode: RENESIS
1996 Toyota Supra RZ: SICKJZA
1999 Mitsubishi Eclipse GS-T in arcade mode: IGOTGST
2004 Toyota Celica GT-S Action Package: MYTCGTS
Free car repair: FIXITUP
Pac-Man vinyl: GORETRO
Mazda RX-7 Bathurst: Finish in first place in every race in the Los Angeles Iron Man challenge in arcade mode.
Mazda RX-8 Mazdaspeed: Finish in first place in every race in the Philadelphia Iron Man challenge in arcade mode.
Mitsubishi Evo VII GSR: Beat the Los Angeles checkpoint mission in arcade mode.
Nissan Skyline V-Spec II Nur: Beat the three Nitro X-treme Crew Meet series in street mode.
Sprinter Trueno: Have all first place finishes in the Miami Iron Man challenge in arcade mode.
Sti: Win the Street Revolution Crew Meet in street mode.
Toyota Trueno Apex: Finish first place in in the Philadelphia Iron Man challenge in arcade mode.