Good subject. I didn't see it written in any of the posts, so I'll add
it to mine. When measuring from the top of my block to the top of each
piston (dial indicator, then with a depth gauge) the difference was .012
to the tallest, and .015 to the shortest piston. If I were to follow the
advice of Kastner, .017 should to be removed from this particular block
to be sure the block were properly decked. This would of course put the
tallest piston at .005 above the deck, into the gasket area, which is
OK.
Kas also suggested that one could then later shave the tops of custom
made (forged) pistons to co-inside with the differences in rod length.
This would bring all of the piston tops level with the deck. It would
seem to me that this leveling of the piston tops could also be done with
the factory cast pistons, if the goal was to have the most accurate
cc-ing of the combustion area. This would mean there would be no
unswept area in the combustion chamber, which is also good.
When decking the (later) block, it would then be necessary to
re-establish the counterbore for the head gasket sealing rings.
Dick Taylor
'73
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