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"Issue #1:  Can the 2.5 be bored successfully to 2.7?  Well, everyone agrees
there wouldn't be very much cylinder wall left after this, so maybe that's
not such a good idea.  My logic here might have been flawed, but I know
someone who has a TR6 and had his blown engine replaced by a Triumphtune
'bored' 2.7 liter.  I was assuming that any 2.5 could be safely bored to
that displacement, as TT doesn't seem to be a hack operation.  I think I was
assuming that the block for the 2.0 and 2.5 were the same, which is probably
wrong.  I know the heads are the same.  I'll contact them and do more
research."
FWIW, you may also want to contact Ken Gillanders, British Frame and Engine,
as I believe he had some 2.7 size pistons (40 thousandths over?) made up.
He said this was about the max for increasing the bore.  I don't know if
California is closer to you than England, but the phone charges and shipping
are probably less.  Sorry, I don't have his number.
 -- Andy Lindberg (GT6+ in Minnesota)
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