Go to the "Options", then choose the "Cheat Codes" option. Enter any of the following cheat codes:
Unlock expert difficulty level: Input VRYFAST as a cheat code.
Unlock all game content (except Story mode races): Input ALLYORS as a code.
Unlock all characters: Input MATTEL07 as a cheat code.
Unlock all bonus art fro purchase: Input BUYTALL as a cheat code.
Get infinite turbo: Input ZZOOOOM as a cheat code.
Extreme acceleration: Input 0TO200X as a cheat code.
Change colors for Lightning McQueen: Input NCEDUDZ as a cheat code.
Change colors except for Lightning McQueen: Input PAINTIT as a cheat code.
Unlock all story-mode wheel sets and Luigi's Casa Della Tires: Input INSTYLE as a cheat code.
Unlock all Arcade mode races, mini games and all Story mode worlds: Input PLAYALL as a cheat code.