Several comments:
1. If there will be several cars from the club, take turns throwing candy. When the car in front of you runs out, your turn.
2. Avoid gum. People leave it all over, and you end up driving through/stepping on it. Jolly Ranchers are also a bad idea. Sweet Tarts, Tootsie Rolls, suckers, and Atomic Fireballs seem to do well.
3. Since you're driving a Fiero, you'll have to consider the logistics of throwing candy. Where will the candy bad be? Will you have a second person throw?