carb ported and manifold vacuum question

Getting the distributor dialed in will help a lot. Below is a link to an article that details how it's done. Something else I do that they don't mention is not only check the reluctor gap with the vacuum advance at rest but also when it's pulled to max. I do this because the reluctor plate due to design just floats there and the vacuum advance doesn't always pull it around in a linear fashion so the gap can increase or decrease some. There is no real cure for that (that I know of) so what you have to do is split the difference. In other words if the gap measures .008" with no vacuum applied to the vacuum advance and .004" with vacuum applied set it where it's .006" with vacuum applied. Any tighter than that and it may not always fire right. You also don't want to go looser than .012" or it may not always fire right, especially if your using a MSD box which seems to like a tighter setting.

http://www.moparmusclemagazine.com/...mopar_electronic_ignition_system/viewall.html