The engines we build usually have 50# of oil pressure at idle when hot , 70
# at 2000 rpm and will go up to 90 # or so at 6000 rpm with 20-50 or 50 sae
oil. The pressure relief valve just gets a different setting for the
different wieghts. of oil. We normally use 40 or 50 sae Kendall GT-1 in our
race engines and chevron 20-50 in our road engines. We used to use Kendall
in everything but they kept raising the price of the oil until we felt that
it had become to expensive to use in the shop for normal road cars. The
chevron is very good oil with very good high detergency additives that keep
the engines clean inside over the long milages that current production cars
live without lmajor engine work. 'The Kendall has better extreme pressure
additives for the stresses 9incured in the high rpm, high loads of racing.
The 40 and 50 weight race oils are used because of the clearances that we
set up in the race engines to compensate for the bending of the cranks and
the distortion that occures in the big end of the con rod at high rpm. With
carrillo rods and a properly prepared crank it may be possible to use
smaller clearances and a lighter weight oil and still have the same good
results.
Regards, Greg Solow
----- Original Message -----
From: "Ronald R Gates" <Ronald.R.Gates@usa.dupont.com>
To: "R. Kastner" <kaskas@earthlink.net>
Cc: "Henry Frye" <thefryes@iconn.net>; <fot@autox.team.net>
Sent: Wednesday, March 22, 2000 8:10 AM
Subject: Re: A couple questions
> This is all good stuff ! my question is , after you hand crank for oil
> pressure , and start up ,how much oil pressure should
> you have at idle and , say 3000 rpm when warned up . I was told that if
you
> use 20/50 racing oil , that meant when the oil is
> cold it is 50 wt. and when it is hot it is 20 wt. I was also told by a
> very reliable tr race engine builder that the tr-4 engine should use
> straight 50 wt. racing oil or 40 wt. racing oil .
> I always used 20/50 in my cosworth fords bdd,s . never had any oil
> problems or pressure problems . anyone have any thoughts on tr-4 oil
> pressures and oil wts . also what kind of oil pressure should you have in
a
> race , coming down the front straight .
>
> pete Gates
>
>
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