What is the compression at idle on a 7-1 compression 276 Desoto hemi? Does anyone know? My compression is even on all cylinders at 135 . My Vacuum is around 13 idling in neutral. I am not use to this low of vacuum reading but then again, I have never run an 1952 small cube low compression engine either. Thanks in advance.
Since compression is equal in all cylinders I would think the rings are serviceable. Did you run a second compression test after squirting some oil in the cylinders to test the valves? It is important to connect the vacuum gauge into a direct manifold port not just any open place on the carb.
Motors manual sez compression 130 psi vacuum seems low check for leaks and late timing the manual sez 4 deg.
....at idle,,,? if you are checking dynamic compression on each cylinder in turn while running, the vacuum is probably affected by one dead cylinder. As mentioned, check timing.
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