tigers
[Top] [All Lists]

Re: [Tigers] How hot is hot ?

To: MWood24020@aol.com
Subject: Re: [Tigers] How hot is hot ?
From: Dave Munroe <dave@munroe.ca>
Date: Fri, 29 Aug 2008 13:14:50 -0300
Optimal oil pressure....

A question I was afraid to ask. I have seen on this list and others, as well in 
propaganda from owners trying to sell their cars, 
claims of oil pressures in their SBF's of 60 psi at "speed".

My oil pressure at start-up cold is 45 psi on the gauge, dropping to 30 as the 
engine heats up and reaches 225 230F at 3,000 rpm and up.
It would drop to 20 at idle "hot".

Now that I have it running at 180-190F, cold pressure is still 45psi. but it 
never drops below 40psi, now, at operating temp.

Hot-rodder's I have spoken with say 10 psi per 1,000 rpm is lots for a "built" 
engine.

What's considered normal or adequate by the Tiger community??

Dave 
  ----- Original Message ----- 
  From: MWood24020@aol.com 
  To: dave@munroe.ca 
  Cc: tigers@autox.team.net 
  Sent: Friday, August 29, 2008 12:28 PM
  Subject: Re: [Tigers] How hot is hot ?


  In a message dated 8/29/2008 8:03:06 A.M. Pacific Daylight Time, 
dave@munroe.ca writes:
    One of the reasons why I worry about my engine overheating ( 225- 230F) is 
    the noticeable drop in oil pressure.

    When you did your oil temp testing on horsepower gain, did your FF oil 
    pressure drop with a rise in oil temp?



  Which, I guess, brings us to another (but, linked) discussion: "optimal" oil 
pressure ;-)

  Yes, we did see drop in oil pressure. Idle pressure, post race, was in the 10 
psi range with about 25-30 psi at anything over 3000 rpm...which was plenty in 
that application, evidently, as we went two years without an engine failure. 
When the motor was taken down, bearing wear was normal. Keep in mind, this is 
just a VW motor, air cooled, low(er) rpm etc.

  The other thing that I didn't consider, when I posted earlier, was excessive 
piston/piston crown heat, which can lead to power loss...in some cases, TOTAL 
power loss...I was thinking more of elevated engine heat in the intended 
operating range.





------------------------------------------------------------------------------
  It's only a deal if it's where you want to go. Find your travel deal here.
_______________________________________________
Support Team.Net  http://www.team.net/donate.html


Tigers@autox.team.net
http://autox.team.net/mailman/listinfo/tigers

http://www.team.net/archive

<Prev in Thread] Current Thread [Next in Thread>