Thanks, Dave. Next question, I had a lot of trouble ( I believe) with the 216 manifolds I have. How can I test the intake to see if it has a vacuum leak? I am thinking to duct tape over the openings for the carburetor and the head ports then submerge it in water to see if there are any bubbles. I'm not sure if that would work. If there's a better way to go about it, I would like to know what it is.
Intakes themselves won't have vacuum leaks, unless they are cracked. The vacuum leaks will usually be where the intake meets the head.
Complicating matters, is the union between the intake and exhaust manifold. If you ever separate the two, you will need to keep the 4 nuts and bolts loose while you bolt the intake/exhaust manifold assembly to the head without the manifold-to-head gaskets in place (for the purpose of mockup and alignment). Once you tighten the manifold bolts to the head, you can tighten up the bolts that hold the intake and exhaust together. Any gaps between the head and the manifolds can be found by probing with a thin feeler gauge.
Carl
