Hi everyone,
When I bought this car in 2000, I adjusted the valves and checked compression, which was 138 psi for 3 of the four cylinders and 95 for the number 3 cylinder. Today, I repeated this check and the 3 cylinders are at 127, with the number 3 cylinder at 82 psi. I put a tblsp of oil in the #3 cyl spark plug hole and the compression came up to 130, so I believe the cause is just ring wear.

The question is what are everyones thoughts on allowable min compression (if not there already) before rebuilding the engine.

Or is the delta between the 'good' and bad cylinder compression too great?
Thanks, and happy new year,
Rick

First recheck your valve adjustment.Repete the test on a warm motor and keep the throddle open during the cranking sumtin about vacuume throws off the test with closed throdle.

DJ,
I got a very similar response from the guys at Pelican, with the addional comment of 100psi being the recommended min compression. I was doing the compression check wrong (cold engine/throttle closed). So will take your recommendation, verify valve clearances, warm up engine then check compression with throttle open.
Thanks for the great advice, I really appreciate it.
Rick