jdb8805

This is 2007 Z06 with 16097 miles
Spec clearance is .0012 - .0025 (as produced)
Service limit is .0037

The gauge moves a total distance of .0080 - .0100 1" above the guide on exhaust #2 EDIT: on remeasure with a more fixed location and removing the Pointed tip of dial indicator, its .0070-.0080
The gauge moves a total distance of .0050 - .0060 in the intake #2
EDIT: remeasure Zero movement on the dial indicator. Maybe .0010
What does this translate into for clearance?

Based on this book

http://books.google.com/books?id=_CQ...tput=html_text

And real world measurements of .0100 wiggle --> .003 or .004 clearance, I believe I'm right at or just below the service limit.

jdb8805

Bump...

HioSSilver

iTrader: (8)

Good find. From what I have gathered it's been a guide problem and not a valve problem. Now why is the guide wearing out early?

msydow

i would think they would measure a new valve stem and measure i.d. the of the guide then subtract the two to find the clearance.

jdb8805

Heads are still on car. Trying to determine whether clearance is bad enough to pull them.

HioSSilver

iTrader: (8)

For sure it is. I would not even start it like that.

jdb8805

I'll assume you opened the page from the google books on small block chevys and read that a wiggle of .0100 - .0150 with the valve 1/4" off it's seat translates to a valve guide clearance of .0030 or less.