I think it all depends on the level you are racing at. Your local Saturday night racing I feel a pit pass and some food is sufficient because the guys working on the car are going to have fun also, and most probably don't want paid. Not saying a little bonus at some point wouldn't make their day, but most of them you could just pay their way and they would be grateful.

Now if you are talking about running USAC or another top division, although some will still be alright with just pit pass and food, it may require some compensation. Racing at that level requires a lot more time and work at the track. The amount of work you expect from your guys kind of depends on if you should pay them extra or not.

Find someone local that you can bring to the shop to learn the car and then they would be more than tickled just to go to the track with you. Good way to get a teenage kid involved in racing.