In a message dated 3/17/98 10:04:52 PM PST, larry.g.unger@lmco.com writes:
<< Bill S. replied:
> The 1622 bore is only about .020 and there is no problem with
> the overbore, ... [snip]
Agreed, as along as you resist the temptation to push beyond the
std. 1622cc pistons ... to say +.040 1622cc pistons ... ;^)
***Not a problem, actually. The factory competition Twincams, which share the
same bore centres and wall thickness as the pushrod 1588, were punched out to
over
1700 cc. The walls are thick, and everything after the 1500 had siamesed
cylinders anyway, so any reasonable overbore, including 1622 +.040" and beyond
won't give problems. I know - I've done it.
> ... but you might have to supply your original wrist pins to be fit
> to the new pistons, as I don't know that the old clamped gudgeon pin
> is that common these days.
Hmmm ... Venolia lists all the various 'A' engines, including the
'Twinkie', in their catalog along with an extensive list of wrist pins
... so I would think that they should be able to supply them.
Yes, but the Twincam is a conventional full floating pin and so poses no
problem whatsoever. I was indicating that the clamped wrist pin with the
groove for the clamp bolt in the small end was no longer common practice and
might pose a problem.
Bill S.
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