That should have been .002" and not .005". Sorry. It was an engine
that had 87mm liners bored to either 88mm or 89mm, I do not remember which.
When they were placed in the block, the pistons had too much drag part way
thru the liner so the owner brought it to me to check. I always test my
piston drag with a fish scale (never used it for fish though) and a wire
hook around the wrist pin. I shoot for 12 lbs. or less of drag with only the
oil ring on. I checked his liner with a bore gauge and my torque plate on
and it showed right at .002" out of round. Almost as if the liner were being
squashed some. It may have been because of too thin a cylinder wall but it
showed distortion. I do not know how the liners were bored as I did not have
them done. And I did not recheck them after removing the torque plate. I
figured the liners were bad so no need to proceed any further with them.
Good race shops will bore their engines with the main caps torqued, a torque
plate on both surfaces (if a v-8), and hot fluid running thru the block. You
know that is how NASCAR shops do it. But, we are running for a less than
$10.00 medallion at most events and the cost to do that at my machine shop
would be prohibitive. Let me also say that I run the steel shim head gaskets
from Mr. Gilander so there is very little give with them as opposed to a
composition gasket. As I build my engine for the Mitty, it may be
interesting to see if there is any change in cylinder distortion with the
liners just fitted in the block, then with the torque plate installed, then
when I remove the torque plate after boring to install the head. I will let
yall know if there is any differences. Barry
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