texasgulfcoast

Experts
I am going to run a Compression test on all Cylinders and I need to know what each Cylinder should read.
If I get A/C Delco Spark Plugs what should I Gap them to? Thanks in advance for your help.

I have a 1991 C4 Basic

Cliff Harris

I don't think there is a absolute compression pressure. The main thing is that they are all about the same.

Gap your plugs to 0.035".

PatternDayTrader

Any cylinder under 100 will basically not fire. If every cylinder is under 100 then you will have a no start.