>From: "Westerdale, Bob" <bwesterdale@edax.com>
>Reply-To: "Westerdale, Bob" <bwesterdale@edax.com>
>To: "'Steven Newell'" <steven@cravetechnology.com>, Twistblts@aol.com,
>Triumph <triumphs@autox.team.net>
>Subject: RE: TR4 cylinder liners
>Date: Thu, 7 Dec 2000 13:44:10 -0500
>
>Steve wrote:
>The thinner walls of the bored liner may contribute to overheating issues
>slightly. While it'll cost slightly less to bore the old liners, it's
>likely
>a
>false
>economy. The 87mm liners are engineered for 87mm pistons, get a
>matched set.
>
>
>Hmmmm.... interesting proposition. I'm not so sure the likelihood of
>over
>heating is caused by the thinner walls. With a thinner sleeve, the heat
>produced by combustion gasses and piston ring friction has a shorter path
>to
>travel before it reaches the water in the jackets. I think this should
>serve to reduce the temperature at the inside (piston) surface of the
>thinner liner. On the other hand, the 87 mm bore raises the compression
>ratio and also burns a bit more fuel, because of the added engine
>displacement. Both of these contribute to hotter engines, no doubt.
> Be sure to ask the Machinist about set up time for this job, as
>nobody rides for free.
>Have Fun-
>Bob Westerdale
>59 3A TS36967
I know I'm late getting to this discussion... I did the deed on my TR4
when I received a set of +.040 pistons... It's been a little over 6
years since the rebore. To date, I have had no overheating probs...
In fact, the car runs a bit cooler now than it did before the
changeover. the other changes done at the time were balancing the
moving parts and lightening the flywheel by about 1/3rd.
Greg Petrolati Champaign, Illinois 1962 TR4 (CT4852L)
That's not a leak... My car's just marking its territory...
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