Successfully complete the Amateurs Group B to unlock the Buster GST car. Successfully complete the Professionals Group A to unlock the Firespitter RS and Pick'Em'Up V8 cars. Successfully complete the Professionals Group B to unlock the Bornbad GT90 and Ironhorze V8 cars.
Bonus weapons
Successfully complete the Amateurs Group B to unlock the minigun weapon. Successfully complete the Professionals Group A to unlock the single missiles weapon. Successfully complete the Professionals Group B to unlock the double missiles weapon.