<VV> A couple of 94mm questions
larry at forman.net
Sat Feb 24 14:35:23 EST 2018
I purchased a "kit" to make a 94mm big bore engine when I was at the
CORSA Portland National Convention. I think that was about 2005. The
machinist was named John and I think the last name was Warner. I heard
that he did good work.
I am now about ready to start assembling that engine for possible use in
either the Devin C or a Rampside. However, I have heard of horror
stories about the 94 mm big bore engines and wanted some advice. I
have heard of some of the 94 mm jugs cracking or splitting at the block
end where they are pretty thin. I checked the bore and it appeared
well within specs for both taper and runout.
I was thinking of taking a junked head and having it bored out so I
could do a trial torqued measurement for possible changes in taper and
runout before the pistons and crank are installed.
My first question:
Is that needed or even recommended or worthwhile?
My second question:
Am I in dangerous territory with the 94mm big bore jugs? They seem
pretty stout and this will be for a normally aspirated engine, so no
turbo pressures involved. The engine is NOT for racing, except perhaps
for the Devin C use in AutoX. Rpms will likely remain south of
6,000. I am interested in an engine that will have plenty of power for
fun but will not require frequent rebuilding.
Since the upper row of head studs have been removed, what should I do
about replacing them? I normally would use TimeSerts, but these studs
are getting pretty close to the larger bored diameter. I am concerned
about taking even more material very close to the edge. Should I
simply replace the studs and call it good?
Thanks for any suggestions,
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