Frankly Glen, I limit my comments to this and other lists because of responses
like yours. I'm not speaking of list surveys nor am I guessing. I'm speaking
from 20 years hands on experience with TR8s, street cars and a race car, and
having built a number of engines. I currently have a fully built 4.6 and a 4.2
short block on engine stands. The TR8 factory manual specifies 1.97 kgf/cm2(28
lbf/in2) pressure at 2000 rpm and 35 lbf/in2 at 2400. Given your assertion,
that would mean that pressure at idle, 750 to 900 rpm, would drop as revs rise,
a most unusual circumstance. One would also then have to wonder why there is a
pressure relief valve in the system. You apparantly do not understand the
proper and careful building of an engine, often refered to as "blueprinting".
It means in essence to optimize clearances and mechanical relationships to
approach that intended by the designer, removing manufacturing variances. A
blueprinted bottom end would give results reflecting just what the designer
intended, in oil pressure and in other ways. That is the way that race engines
such as those I have built, using stock components, are put together. You
apparantly do not understand oil viscosities either. 20w50 is one of the
viscosities recommended for the TR8, but not the only one. It was a common oil
in the 70s before the feds imposed fuel economy standards and before
manufacturing processes allowed much less variance in clearances as is now
true. Engines running the same bearing clearances now use 5w30 because it is
easier to move at cold start, resulting in less wear in that time when most wear
occurs, and because it contributes to fuel economy. Increased pressure in
itself does not incxrease protection or lessen friction. It is necessart only
that there be sufficient pressure to maintain the oil film that separates one
part from another. Smokey Yunick, one of the most respectred "hotrodders" ever
has often stated that an engine needs only 10 #/in2 per 1000 rpm. 20w50 and the
like is often used in engines with larger clearances due to wear. You are of
course entitled to use that which you choose, but it is not helpful to make
guesses without the background needed to understand what is actually happening.
Am I a hot rodder? Perhaps, but I respect the advances made by those much more
capable than I. Do you still use the tires, lubes, fuel and coolants originally
specified. I doubt it, because most are no longer available, having been
supplanted by newer products. John
Glen Wilson wrote:
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