I believe standard # of cranks is 5.

If it took 8 to get those readings, with a -recent- head rebuild, I'd lean toward rings a bit sloppy if all else was at spec. Needing a valve job after 60,000 just does not seem necessary unless the head rebuild was screwed up.

Not ruling out a bad head job but I'd look elsewhere to spend a lot less before redoing the head.

I'd go to the 5 stoke test, then retest with a teaspoon of oil in each and see if compression goes up and evens out. The oil indicates only the rings.

I'd also connect a vacuum guage and see how it reacts at various RPMs. Cold and at operating temp. Needle should be rock steady. How it moves is indicative of what may be wrong. Somewhere on the net is how to read them. I know from experience and there is not enough room to write the book on what type of needle reaction means what. I use a base vacuum of 16-18 with low compression hihg milage engines.

I've had a leaking brake booster (massive air leak after the AMM) give a similar span of readings with a similar higher range when oil added. Rough idle with high NOx and slightly higher operating temp were original complaints.

Duane