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That's not what I wanted to hear. Our compression levels are between 118-120 on all but one cylinder, #6, which is at 109. We've got a big problem, then.
It's a new rebuilt. My father and I rebuilt it complete. Ours was also bored 30 over. Now, if the psi should be at 140 and ours is at 109, 118-120-- isn't that too low for a brand new engine? What could be causing this?
What's the compression supposed to be for a 351 C 2V? I rebuilt my engine, had my heads shaved. There's no carbon on the heads or anything and all the cylinders were up around 160-180psi..
Wild,
Just answered your other string. An 8.0:1 compression ratio should yield about 125 PSI. If the lifters are not pumped up before valve adjustment your wasting your time.
Is the Cam stock? If not, what is your lobe offset? This can effect your compression test. The smaller the offset, the lower the compression. I think 109 degrees is factory. Low compression will screw up the emmisions test. Readjust the valve after you've primed the lifters. A 5/16 or 8mm socket will drive the oil pump driveshaft on a 302. I don't knot the 360 size right off hand.
KingFisher
In order to get an accurate compression reading you would want the lifters pumped. After cranking a while they should get there. You also have to prop the carb fully open and remove all the plugs. It can make a big difference in the reading. If the enigine hasn't been fired the rings haven't had a chance to seat either.
Bear Tracks
P.S. A lot of cranking is not a good thing for a new engine.
All,
If the valves are adjusted before the lifters are primed then they will remain collapsed. The valves must be loosened and the the lifters can be "pumped up".