To use these codes you must be fast enough to have your time entered
on the high score screen (make sure to turn checkpoints on from OPTION screen.)

            knacked - Reverse tracks
            whoooosh - Nitros (press HORN while racing)
            mjcim.rc - Tiny cars
            sausage - Bonus cars
            cup of choice - unlock all cups
            that takes me back - enable backwards mode
            i have the key - unlock all cars and tracks
            Note: After entering the codes make sure you save your game.
            Otherwise, you will have to run this each time you play.

            Also, if you use the Nitro code don't try it until you're in second
            or higher gear. Otherwise you'll spin out.