Need for Speed: Underground -- Rivals Cheats, Codes, Hints, Tips
Unlockable: Subaru Impreza WRX STi
To unlock the Subaru Impreza WRX STi, race against the Boss Car using an American car in a Cup-level Boss Race.
Unlockable: Nissan Skyline R34 GTR
To unlock the Nissan Skyline R34 GTR, race against the Boss Car using an American car in a Trophy-level Boss Race.
Hint: Boosted Acceleration
In drag racing if you tap the nitrous button instead of holding the button down your car will accelerate quickly, but in a manner you can find easier to control.
Unlockable: Chevrolet Corvette Z06 and Nissan Skyline R34 GTR
Select the car and proper race level until you're goiing up against the boss car you want to unlock. Then beat the car at the MASTER-level Boss Races. You'll find them available in your pocket garage.
Unlockable: 1969 Dodge Charger and Subaru Impreza WRX STi
Select the car and proper race level until you're goiing up against the boss car you want to unlock. Then beat the car at the PRO-level Boss Races. You'll find them available in your pocket garage.