Anderson Ed wrote:

Thanks for the yarn suggestion, Jeff.

 However, I am really limited (due to lack of adequate foresight about
where I could expect to encounter problems) in where I can put the
opening.  I originally had the NACA duct lower down on the cowling more
parallel to the local airflow.  Unfortunately, with the opening in that
position my air flow duct to the oil plenum had to make two 90 turns
just to get air into the plenum (that did not work).

So until I am ready to undertake some major shifting of the
under-the-cowl space allocation, I am pretty much stuck with the opening
where it is.  Realizing (now) that it is apparently not the place for a
NACA type duct, I am focused on trying to determine what type of opening
would likely capture the external airflow better.  Paul Lamar had
suggest a snorkel type opening.  I presume that is not unlike the lower
air intake for my engine which has an approx 3" dia opening that
protudes approx 2-3 inches into the airstream ahead of the rest of the
cowling.

When initially allocating space for all the under the cowl subsystems
and components, it never dawned on me that the oil cooler would be the
thorn in my side that it has been.  I mean - with most reciprocating
engines the oil cooler is more or less optional unless you have a high
output engine.  I just never really realized the full significance of
the statement - that the rotary dumps 1/3 of its rejected heat throught
the oil cooler - but I do now {:>}

Ed Anderson

Try that snorkel. Make it look just like your carb air intake Ed.
Rather than try to carve out the inside of the foam and you can make 
it in two peices. Inside and outside with a nice transition to
your five inch hose. If that does not work you will have to work on
the duct.

Paul
 
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