Vacuum is one part of the equation but comp, manifold, rpm's cubic inches, single or dual ALL have an effect on the needs and every time I go bigger on certain motors they pick up and some a BUNCH......


72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....