If your pistons stand proud of the block a bit it shouldn't hurt. Depending of
course on how far. My block was decked pretty severely so my pistons stand
.015 proud of the block. My head is barely shaved though. I took this route to
maintain as much of the combustion chamber as possible. Plus it leaves me room
to shave the head some more later if I feel like it. If my head were severely
shaved, to achieve more than 10.5:1 CR say, then I might need to worry about
rod stretch at sustained high RPM (as in over 5500). The standard head gasket
is fairly thick as well. Going to a copper gasket might actually bump the CR a
bit.
just my $.02 though
Otherwise, Dick's advice is very sound. Especially all of the balancing. Very
important for smooth power.
Shawn J. Loseke
1972 TR6
Fort Collins, CO
>===== Original Message From tr6taylor@webtv.net (Sally or Dick Taylor) =====
>Joe wrote:
>....I plan on shaving the deck to obtain a zero deck clearance. I'm
>almost certain that this would eliminate any marks on the deck.
>My question is 1) Do I determine how much to take off the block by
>measuring with the current crank/rod/piston configuration, or do I
>assemble the engine with the new components and THEN measure the
>clearance?
>
>Joe---Whichever set of rods and pistons you decide to use, measure from
>the top of the lowest piston at TDC to the top of the deck. This is the
>amount that you can shave from the the deck.
>At this time, several of the pistons may be over the top of the deck.
>These piston tops should then be shaved to get them all even again. The
>only penalty for not doing this final step could be some differences in
>the CR from hole to hole. There should be no interference at the head or
>gasket.
>
>Shaving the pistons tops would then require new balancing of these
>parts. (Weight will be taken from the skirt area). All pistons should of
>course be marked and weighed, after numbering them.
>
>...2) Can the pistons run a little "proud" of the block? I'm sure the
>gasket would prevent any interference with the cylinder head.
>
>See above.
>
>.. 3) would the use of a copper gasket vs the fiber gasket eliminate
>any problems with small scratches/nicks on the deck surface! ? ThanksJoe
>Davis
>
>Others better qualified can answer as to the advantages of the copper
>gasket. If you use the "standard" gasket and deck the later head, you
>may then want to do the counterboring of the cylinders, so the gasket
>will fit down into each bore. If you leave the head "flat" then I think
>you can use the early head gasket, or one made of copper.
>
>Dick Taylor
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