Hi Friends !I got a bunch of questions.Before starting,my Elly is a 86 SS,305 w/a four barrel stock (wires going to it) carb.,auto trans.AC,cruise. I was wondering if changing over my electronic distributor (that sends signals to the ECM) to a vacuum advance,high output coil, distributor is a good idea ? Will it increase MPG's ? What other things will it affect and the most cost effective way to handle those problems? With the high output coil,should I increase my plug gap?The new coil comes with a allen wrench for adjusting the the vacuum advance? Can someone clarify what that means ? Thanks, in advance to all replies.