Type in XYZZY during a race. No screen will come up, and no sound will be heard, so there is no way to tell if you screwed up.
After typing in XYZZY, type:

BRIBE: removes police officers
K'THUNK!: gives you a bat - invalid code??
SPOON!: gives you nitrous oxide
THWAK!: gives you a chain
PLUGH: disables cheat mode
YES,OCCIFER: no cops