Multi-Racing Championship cheats and cheat codes for Nintendo 64

Play with bonus cars
Select 2-player mode, and choose one of the inaccessible garages.
After, leave the 2-player mode, and begin a single player race
without choosing another car. Now you can use one of the
previously locked cars.

Hannya as opponent: in challenge mode
Win 1st place on all 3 courses in championship mode.

Show the time trial score for the Mountain course:
Hit R at the title screen.

Unlock Match race mode
Win 1st place on on each difficulty settings in championship mode.

Faster start
Hold Accelerate when the timer reaches 1.

Unlock Hannya car
Beat Hannya on all 3 courses.

Race with Dues car and mirror tracks
Beat Dues on all 3 courses.