Jerry, I think the cam is 218/218 duration, which could be the lower vacuum reading. The Performer manifold should be fine and the Holley would be a direct bolt-on, I think the Q-Jet was introduced in '65? My '57 283 2 bbl. with 2 degrees more static timing than stock will idle at 560 rpm with 18", I'm about 500-600 ft. elevation. LAJones, do you trust your vacuum gauge, do you have something to test or compare it to?
Last edited by 78buckshot; 11/20/2024 7:41 PM.
