On the menu with the manufacturers (Toyota, Honda, etc.), move the gear shifter UP, UP, DOWN, DOWN, UP, DOWN, UP, DOWN then hold BRAKE and press VIEW CHANGE.
An engine rev sound will confirm the code.
Select Subaru and the GCV8 is now a selectable car. The GCV8 cannot be tuned, and can only be unlocked in version 2 of the game.
Hold START for two seconds on any night race, and you can race in the dark.
Select either Time Attack or Story Modes. Press VIEW CHANGE at the stage select menu to cycle the songs played.
Press START while in a race to choose between accepting or declining a challenge. This is only available in version 2 of the game.
Ever wonder how someone you race can catch up so quickly when they're so far behind? It's a boost command. If you're racing someone (for linked machines only - this doesn't apply to races against the AI) hold the BRAKE down when the game is loading. This will make the racing experience a little more realistic.
This usually works with the Lancer EVO car. When you start a race, shift to the right twice as the countdown runs out and the car usually (but not always) starts quickly. The version this works on is unknown.