compression numbers

[fusername]

figured I would ask here, as the t4urm doesn't seem to know.
when doing a compression test on a 2.0, what are the wear limits, range, etc? I am going by vws numbers, and was shocked at what my junk engine pulled off. from ratwells site, vw says;
* 1700cc: 100-135psi, no lower than 85 psi
* 1800/2000cc: 85-135psi, no lower than 71 psi

since my motor hadn't been spun in several million years approx, I sprayed some oil penetrating oil down the intake and sparkplug holes. when I cranked it over not only did I mist my entire interior with oily spray, but I read 160. lovely. oil pressure was 25. I let it sit for a day, and did the compression test again, but dry, and hit 130-140. So I take it vws specs don't apply here.

also I have second motor, but I didn't do a compression test as someone stole the oil cooler off it. is there anyreason someone would do that aside from they need the cooler? I am afraid something blew up in the motor, and then they pulled the cooler as part of a fix and gave up halfway thru. the motor still had a fan shroud, intake etc still on it. gives me the creeps. I just want to throw one of these motors into my bay as a replacement that is in better shape than its 1700/2000

[david58]

As a rule of thumb you need at least 100 psi on any gasoline engine on each cylinder for it to make enough power to burn the air and fuel mixture. If it aint sucking it can't blow. Let's say you have one weak cylinder for example lets say it is 60 psi. The other 3 cylinders are 125 psi. The weak cylinder can't burn the mixture at idle but lets say at 2000 rpm's it does to a point. It fires and makes enough power because the compression goes up with the rpm's. It still doesn't keep up with the other cylinders. The faster the air is compressed in a way slows the leak down as long as the leak is small. A compression test is done with all the plugs removed at the cranking speed of the starter. Not at 3500 rpm's. I have never checked the compression on a engine at 3500 rpm's but I think the results would be much higher readings. And possibly a broken gauge. I think I have a compression gauge that I can use for a diesel engine that I can adapt to test to confirm the results. Now all I need is a weak cylinder to test.