Peter---I'm going to go out on a limb here and say that the modern head
gasket doesn't require retorquing at some later date, as once done in
the past. I can't be as confident in saying this about the earlier
engines, since they don't use the same gasket as the later ones that
have the steel ring that nestles in the piston counterbore. Gasket
makers like FELPRO says it's not necessary for most of their products,
so does this mean that head gaskets from our major suppliers also don't
need re-tightening? It would seem that one could tell if the gasket
'shrunk' (or whatever happens when it goes thru a few heat cycles) by
re-applying the torque wrench set to the value of the previous
installation number. If you are able to get the 'exposed' nut/s to turn
a little, then the ones under the rocker should also be checked. I don't
know how accurate a torque wrench would be if used with a crows foot.
Loosening the nut/s before tightening would be one way to be sure the
nut and bolt didn't bond in the period prior to the recheck.
It would be interesting to hear from owners of earlier cars to see
whether or not they do the retorque, and why...
Dick T.
'73
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