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Subject:Re: Synthetic oil (Revisited -- Briefly)
Date:Sat, 3 Feb 1996 12:40:38 -0500

In a message dated 96-02-02 21:35:54 EST, MIKE.WHITE@law.utah.edu (Mike
White) writes:

>As I understand it, the synthetic stuff sheds heat better.  That's 
>great and all, but that means that more heat is being transferred 
>into the engine case.  Not what we want.  We want the heat in the oil 
>until it goes to the cooler which then effectively cools the oil.  
>Sure the synthetic stuff would cool better in the oil cooler, but I 
>don't want the heat in the case.
>
>Again, this is based on what I've been told, and some random logic 
>(combined in no particular order!).

Oil cooler sheds heat by design.  Oil itself is actually an insulator.  That
why tube and fin cooler work so poorly.  The oil on the outside of the tube
thickens,  forming am insulating layer that allows hot oil to flow through
center dissipating very little heat.  Thats why inserts are placed in tubes
 to rotate or mix the oil.  This is often called a skin effect.  Flat plate
coolers such as the original equipment are extermely effective for thier
size.  Synthetic oil does not change heat transfer charecteristics that much.
 Reduced friction, and improve flow and pumpability characteristics cause
reduced total heat that needs to be dissapated.  Case is also part of cooling
system and there is no problem transferring some heat into it.  That is why
it is also finned, increased surface area.  Synthetic oil also has the
advantage of lasting much longer.  Most oil contamination in a healthy engine
is from the oil itself brealing down.  Synthetics virtually eliminate this
problem.
Dennis.