Kevin- I was looking through some old Automotive adn Chilton manuals last night. If your vacuum is staying consistantly low at 5 and does not vary it points to the intake leaking, there are so many things that effect vacuum like bad rings, valve seals, valve timing, cam timing, leaky head gasket, manifold etc.... but if the intake is leaking vacuum will be consitantly 9-10 points low. I alwyas pull vacuum off the empty port on the vacuum tree, how does your brake pedal feel when it is sitting at idle? WIth only 5" it should be stiff because my old cam only pulled 9-10" of hg at idle and that is not enough to operate the power brakes.
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