Quote Originally Posted by 53 Willys
Denny Thanks for the answer, Much better than the one that edelbrock sent
"There is no maximum, but too much clearance means that there is no quench, which means no power. Anything tighter than this, or the head gasket thickness, there is potential for piston to head contact depending on the connecting rod or rpm. Thanks." Me thinks the best way to cover your butt is to not completely answer the question.
You are talking about something that has way to many variables.
If I build a stock type engine I just make sure you have a min.of .040 and call it good.
On drag race engines you can get by with .030 with good steel rods for good alum. rods you would need at least double that and maybe a little more depending on rpm's.
On a IMCA mod engine we try and shoot for .050 because even with good 4340 h-beam they will grow some.
Like I said it really is an open ended question.