Okay, I'll go with the rpm air gap then. As far as the carb goes, I see there are 2 choices with the holley: either a vacuum secondary, or a double pumper...which should I choose? I was thinking the d.p. because I'm afraid with that cam I won't have enough vacuum at low rpms to support my brakes with the vac. second. carb....does that sound right? I'm mainly going to be autocross/road racing the car, but want it to be manageable going to and from the track...oh yeah, I haven't found any heads yet. I'm on a budget, and will be looking for used heads. Thanks for your help guys...