So to carry this thread on longer the variation here is 30psi.
Is that average/normal?
What should it be cold? compared to 170psi when warm and new.
Cams, head gaskets can create variation as well as a looser build for higher end builds/power
Worn engines reducing in compression due to wear.
A cold compression test can tell you as much as a warm compression test. At least when it's cold you have a better chance of picking up irregular noises.
Hence the no greater than 10% across all 6 as a general rule.