> > Russell,

  As I recall from discussing this with Fred Moreno, the lower delta T

is

more than offset by the fact that the oil/water cooler transfers heat

much

more effectively than a conventional air/oil cooler. That is for a given
amount of heat transfer area (core size) the oil/water core will

transfer

much more heat than the oil/air cooler. Unfortunately I cant locate the
email he sent me which gives hard numbers that show this.

Mike Wills

Ed Anderson wrote:

 Mike, while I believe the analysis you cited is correct, I think that in
the final analysis the air flow must remove the heat from the system.
Whether you transfer it from the oil to the water first (via the oil/water
interchanger) or directly cool the oil with the air stream - you still need
the same number of BTUs transferred out of the system into the air stream.

I think that the oil/water interchanger has merit where the availability of
your cooling air is remote from your engine location.   So that you can put
the larger radiator where most convenient for getting the cooling air and
rather than having both coolant and high pressure hot oil lines running to
coolers in that location, you use a heat exchanger and transfer the oil's
heat to the coolant near the engine and then the coolant lines transfers the
heat to the radiator and airstream.  My 0.02 worth

Ed Anderson

 
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