An enigma insues...

[Pete]

Originally Posted by Paul Workman

Pete, I see the valve lengths vary from 90-92 vs. 93-95. And, from that same link source, there is no difference in lifters across all years, if I'm reading it right. SO.....Where is the difference in the lengths being made up? Is there a difference in the base radius of the cam lobes, or seat depth in the heads, or does the lifter just suck it up?

P.

Paul,i don't think there is a difference in the heads since most have Birmal heads.
Since the later (93-95) valves are .020 shorter this would tell me the later lifters have .050 tolerance where as the early lifters have .030,i don't have documented proof on this but logic tells me this would be it,i don't think GM would make 2 different Birmal heads.
Basicly same happens when i use a regrind cam when regrinding a cam we take off about .030-.060 off the cam lobe depending on cam specs so if we minus .040 off the base circle then it only preloads the lifter .035 instead of .075 (stock)

Hope you guys are getting this,again if not ask away,there's no such thing as a dumb question.
Like i said this needs a visual much easier to understand,like sex. LOL

Pete