How about the exhaust system? Try this- - - - -put a vacuum gauge on the manifold, and try running the engine up to 2,000 RPM or so at no load, just accelerating in neutral. If the manifold vacuum drops, or won't rise above the point it was at idle, loosen the exhaust pipe to create a leak at the manifold flange and see if there's a change in the vacuum response. Also try a road test and look for a severe vacuum loss on acceleration. You've been concentrating on getting the air in- - - - -now try getting it out of the engine efficiently. I've seen exhaust restrictions cause your identical problems on several occasions.
Jerry

Edit: You can check for cam timing by watching the #6 cylinder rocker arms. Roll the engine over by hand and find the "overlap" point where the exhaust valve is closing and the intake is opening. That should happen very close to top dead center of the #1 and #6 pistons if the cam timing is right. That's also a good place to set the points to fire the #1 spark plug for initial timing.
Jerry


Last edited by Hotrod Lincoln; 12/10/2009 1:55 PM.
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