Normal vehicles aren't half as effective as racing vehicles in racing events. They don't have the same acceleration, the same speed, the same handling or braking abilities.
Still, thats life huh?

A normal vehicle has something like 4 tyres, 4 brakes, 2 engine, 2 body and 2 handling.

Special Rules:
These vehicles may only ever use 1 brake point in one turn. They may also only ever decelerate by 2 gears at most, and going down two gears costs 1 brake and 1 tyre point.

Acceleration wise, they have a minus 1 to all gear rolls for the turn that they go up a gear. Staying in the same gear as the previous turns mays that they don't have this minus one.
They may also only reach 5th gear.