Increase the Prize Money:
At the press start screen press L, R, Z, L, R, Z, L + R.

Extreme Lap Challenge Mode:
At the press start screen press L, R, L, R, L, R, Z, L + R.

Unlimited Turbo Boost:
At the start screen, press L + R, Z, L + R, Z for Infinite Shields. This will also give you unlimited turbo boosts. To turn this code off simply repeat the button sequence.

Unlimited Ammo:
At the press start screen press L, R, L, R, L+R, Z.

Access all Tracks/Teams:
At the press start screen enter L, L, R, R, Z, Z, L + R + Z.

Automatic First Place:
During a race press L + R + Z, L + R, Z, L + R + Z you will win the race even if you blow up or quit.

Hints

Access Team Starcom:
Beat the entire career mode to access the Starcom team.

Sound Barrier:
Once your racer hits 750 mph you break the sound barrier and everthing go's quiet

Thanks to Revolution reader Racer X and Death!