Need for Speed: Underground Cheats

easy drift points:
Simply stay behind a car and watch the points rack up.
Unlock all sprint tracks:
Go to the main menu then hit up, X, X, X, R, down, down, down.
easier drag wins:
To get to higher gears quicker in drag races, tap L repeatedly to increase the revs to the appropriate level to switch gears.
Unlock all drift tracks:
Press Left(4), Right, X, R, Y at the main menu.
Unlock all circuit tracks:
Go to the main menu then hit down, R, R, R, X, X, X, Z.
Unlock drift Physics on all cars:
Go to the main menu then hit R, up, up, up, down, down, down, L.
Unlock All drag tracks:
Press Right, Z, Left, R, Z, L, Y, X at the main menu.

Enter codes while in the main menu screen,then enter your desired cheat.

Here are all the cars in the game,

Acura Integra Type-R, Acura RSX, Dodge Neon, Ford Focus ZX3, Honda Civic Si Coupe, Honda S2000, Hyandai Tiburon GT, Mazda Miata MX5, Mazda RX-7, Mitsubishi Eclipse GSX, Mitsubishi Lancer ES, Nissan 350Z, Nissan Sentra SE-R Spec-V, Nissan Skyline GT-R, Peugeot 206 S16, Subaru Impreza 2.5 RS, Toyota Celica, Toyota Supra, Volkswagen Golf GTi.

Hope this helped!

A good car for easy style points in drift mode and drag mode. no level upgrades

Use the following customizations to reproduce the Brian's Nissan Skyline from 2Fast2Furious:

in the main screen enter this ----> seemylvl2parts.

Unlock the Mystikal car by doing 10 laps on drift track 1 and play
through underground mode to get drift track 6.For maximum prizes get the
Mystikal car and go to drift track 6 and set it on 10 laps. I have
gotten 330,115 style points and unlocked 9 prizes literally!

To unlock all visual upgrades for single and multiplayer mode, simply complete Underground mode.

Look for alternate routes on your in-game map while driving. These can get you ahead of an opponent easily or shave off seconds on your timer. They will look like another road on the map, but sometimes are narrower. Most of the time these shortcuts will be hard to see or take, and can be extremely risky.