EAC POWR: Gives you the "Warrior" car, an 800bhp car, capable of over 260mph.
EAC RALY Changes the track that you are on, try it and see...
EAC WARP Makes the game faster by improving the handling of cars and making the enemy better.
EAC 4X4R Removes all the 4X4's, trucks, and vans and replaces them with cars.
NOTE: If you wish you can combine the codes, i.e. for the code you could put in EAC RALY POWR.