NASCAR THUNDER 2003 UNLOCKABLES
Unlock Tiburon Speedway track
To unlock this track simply use a memory card with a saved file from an EA Sports 2003 game.
Unlock Thunder Plates
Choose the Thunder Challenge or Lightning Challenge at the game mode screen. Finish the various challenges to get new Thunder Plates. Remember that the thunder plates are awarded randomly, therefore it doesn't matter which track or driver you pick.