I don't use the straight edge ............. I use a feeler gauge that
will go down the spark plug hole and measure between the piston top and
the head with the head torqued down.
You can use soft hollow core solder to get this reading if you don't want
to cut up your feeler gauges to insert in the spark plug hole. Crush the
solder then mic it.
I've also used thin wall 1/8" soft brass tubing to get this measurement.
TDC isn't a problem, just bring the piston up to and over TDC and you got
your reading.
My way gives true clearance between the head and piston.
This is my way ............. I'm not trying to start flames.

Stan Wilder

On Thu, 20 Feb 2003 09:06:38 -0800 Tom Young <tomyoung1@ATTBI.COM>
writes:
> Hi all:
>
> Someone recently posted the following link
>
> http://home.hiwaay.net/~langford/corvair/valvejob.html
>
> which details, among other things, setting the Compression Ratio
> (CR) of a
> Corvair engine.  It's a pretty good write-up and very pertinent to
> folks who
> work on VW engines.  However, about 3/4ths of the way down the page
> there's
> a picture of a setup, which employs a dial gauge, that the author
> used to
> determine deck height, but he doesn't describe *how* this setup is
> used.
>
> When I've measured deck height on the Vanagon engines I've rebuilt
> I've used
> a dial gauge to get the piston to TDC, then used a straightedge and
> feeler
> gauges to determine deck height.  I've often wondered if there was
> some way
> I could use the dial gauge to directly measure deck height, but
> haven't
> figured out how.  Do you think the author is merely using the flat
> bar
> across the top of the cylinder as a straightedge, to be used with
> feeler
> gauges?  Or is there some way, using the pictured setup, that you
> can use
> the dial gauge to determine TDC *and* deck height?
>
> TIA.
> ---------------------------------------------------------------
> Tom Young                       '81 Vanagon
> Lafayette, CA 94549         '82 Westfalia
> ---------------------------------------------------------------
>
>

________________________________________________________________
Sign Up for Juno Platinum Internet Access Today
Only $9.95 per month!
Visit www.juno.com