Enter these codes by pressing Up, Down, Left, Right at the Main menu. This will take you to a cheat console where you can enter the following 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

Subaru S202 Sti:
SICKGDB


Unlock the following by completing the corresponding

Nissan Skyline V-Spec II Nur:
Beat the three Nitro X-treme Crew Meet series in Street mode.

Sti:
Win the Street Revolution Crew Meet in Street mode.

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.

Toyota Trueno Apex:
Finish first place in in the Philadelphia Iron Man challenge in Arcade mode.

Sprinter Trueno:
Have all first place finishes in the Miami Iron Man challenge in Arcade mode.

Mitsubishi Evo VII GSR:
Beat the Los Angeles checkpoint mission in Arcade mode.