Initial D Special Stage Cheats

To unlock Bunta's car for use in Arcade or Time Attack mode, defeat Bunta in Story Mode (Stage 31). After beating him, the GC8V will be available in car manufacturer section under Subaru.

By the way, this car only has one default tune option, and it only comes in one colour.

Play arcade mode and beat every single character. After doing so, Takumi will be unlocked for you to race against in Happogahara. Beat Takumi, and you will unlock 5 extra courses in which you re-race certain opponents (i.e. Skyline, Sleighty, etc.) in their story mode courses instead of their lower difficulty levels from before.