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Do you have symptoms of possible compression problems? Rough idle, low speed misfire, excessive blow by, low power etc? If your not having problems I would not be to concerned with the results as long as no cylinder(s) have less than 110 PSI the engine is still usable though power output will be less than optimal. Differences of more the 25% could cause poor idle quality.

I do not know the exact spec for your engine but 130 to 170 PSI with no more than 20% variance highest to lowest is a good rule of thumb. Test with all spark plugs removed and the throttle blocked open, same for choke plate. Use a battery in good condition with a full charge. I like to use a remote starter switch so I can watch the compression gauge closely. Crank the engine though 5 or 6 compression strokes while paying attention to the pressure increase per compression stroke. Try to crank though the same number of compression strokes on every cylinder. Tight engines will build compression quickly and max out before cranking though 5 or 6 compression strokes. I then write down the PSI reading at each of the compression strokes not just the final reading. This maybe tough to do and is kind of a subconscious thing. Even if you only write down the final reading watch how fast each cylinder builds compression. Cylinders that build PSI more slowly are not as healthy as others that do even if the PSI results are the same. If the final PSI numbers vary by more then 20% perform a wet test by adding a small amount of engine oil to each cylinder while re-running the test. If the PSI increases substantially on any cylinder(s) points to ring problems. Cylinders that still test low have valve problems or possible head gasket or other related problems. A cylinder leakage tester though expensive is a much better way to determine what is causing low compression.

As far as figuring compression ratio into cranking PSI, it can be done but the camshaft used and the cranking speed can have an affect. Generally the higher the compression the higher the cranking PSI when using the same cam/cam timing.

Bill
 

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Thanks,
I have no symptoms whatsoever. I just want to have an idea of what I got. It starts fine, does not smoke but will stall out when i put it in gear. I highly supect it is a carbureator problem. There are no ticking noises, no exhaust manifold leaks, nothing! I was given this car a few years ago and am just now having the time and desire to really work on it. I appreciate the info and the things to look for and or trouble shoot.
 
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