Very probably true, Ric! An over-bored XPAG fitted with what were known as
"High-top" pistons (they had a big extra piece above the normally flat
crown, which practically filled the combustion chamber) and the Laystall
head would have given at least 12.5 to 1 compression. As you said, it would
have had to run on "fuel", as opposed to the 92 octane gas available at the
pump today. It would still work today for Vintage racing, using Racing fuel
(but, last time I bought that, about 18 years ago, it was $4.00 a
gallon........dread to think what it is today!)
Lawrie
-----Original Message-----
From: rjs <rjs@computan.on.ca>
To: Lawrie Alexander <Lawrie@britcars.com>
Cc: Bob Peck <bobpeck@mother.com>; mg-t@autox.team.net
<mg-t@autox.team.net>; Dick Dell <rddell@mindspring.com>
Date: Sunday, June 27, 1999 9:39 AM
Subject: Re: overheating TF
>Hi! It has been many years since I used to drive a TC. I was under the
>impression that my TC had 13:1 compression. Am I dreaming, has senility set
in?
>The car was modified for racing, used a Laystall Aluminum Head, and when
racing
>ran on "fuel". I was also told the car crossed the finish line doing 105
mph.
>Should I research my story better, or is all this possible. I never raced
it but
>it sure was fast! Too fast, while going through a tight S bend on the way
home,
>I gather the oil sloshed the wrong way, the pump starved, and the rod
knocked. A
>divorce forced the sale and I never got to see it repaired. Ric.
>
>Lawrie Alexander wrote:
>
>> Dick,
>>
>> Thicker-than-stock gaskets for XPAG/XPEG engines are not readily
available,
>> unfortunately.
>>
>> Even using Premium gas, it's not wise to go over 9 to 1 compression
(about
>> 160 lbs. cranking pressure, typically) with a cast-iron head and the
>> relatively primitive combustion chamber shapes found in Ts, As, Bs and
>> Midgets. The almost inevitable pinging will eventually destroy the rod
>> bearings or even crack a piston.
>>
>> I've used two head gaskets in many engines, without problems. Of course,
>> it's sensible to use new head studs as well, to coat both gaskets with
>> Copper-Kote and to be very sure to re-torque as soon as the engine
reaches
>> operating temperature, then again after about a dozen starts and stops of
>> the engine.
>>
>> I also make it a habit to torque any head down when I first install it,
then
>> re-torque it just before I start the engine. It's surprising how much
even a
>> single head gasket will compress under initial torque and the second
>> go-round always gets some additional movement on the head nuts. Better to
>> spend a few moments re-torquing than to blow the gasket on start-up!
>>
>> Lawrie
>> British Sportscar Center
>> -----Original Message-----
>> From: Dick Dell <rddell@mindspring.com>
>> To: Bob Peck <bobpeck@mother.com>; mg-t@autox.team.net
<mg-t@autox.team.net>
>> Date: Sunday, June 27, 1999 6:53 AM
>> Subject: Re: overheating TF
>>
>> >At 04:47 PM 6/26/99 -0700, you wrote:
>> >
>> >> I am using two <gaskets> as previous owner apparrently milled the head
to
>> >>increase compression to about 9.6 to 1.
>> >>
>> >
>> >Bob,
>> >
>> >Just a quick note. While I have never used two gaskets myself I have
heard
>> >that it is a practice to be avoided. Back in my hotrod days when we used
to
>> >fool around with engines quite a bit I was tempted to use two gaskets to
>> >bring down the compression on an engine I'd bought. The engine rebuilder
>> >told me that was a sure way to blow head gaskets. Could this have been
>> >your problem from the beginning?
>> >
>> >My solution at the time was to use a single, extra thick gasket that was
>> >available from the speed shop. Not sure if such a thing is available for
a
>> >T-series.
>> >
>> >Could you live with the 9.6 : 1 ? You're going to run premium gas
anyway,
>> >I'm sure.
>> >
>> >Dick Dell
>> >
>
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