Various codes
For copies of the game with code 1457, the following cheats apply.
Go to options > secrets > enter code. Now type any of the following codes.
Code Vehicle
AERCNU Baja Buggy
NPDATU Jet Fighter
FHILLB Hovercraft
WFDDBU Tank type
NEWUOT All Cars
UYNUUR All Tracks
AUNIPE All Parts
UZVKFB All Difficulties