Hi Bill

Yes, current ducts are working just fine in the cooling department.
However, I felt that the duct shape was probably causing "eddies" around the
inside of the opening and disrupting some air flow/cooling.  Plus the
current openings are 24 square Inches for each radiator.  I thought that if
the smoother transistion from duct to radiator improved the air flow into
the duct then perhaps I could reducing the opening.  However, Paul, may be
correct  about my old duct cooling better as I reduced the opening from 25
in^2 to approx 10in^2 on the new duct. Perhaps a bit overly zealous {:>).

If the new duct does cool as well as the old duct, then I believe I will
have reduced some of the cooling drag, if not, then I rip out the foam and
go back to the old duct.  Hope to make first flight tomorrow and will let
everyone know of the results.

Ed Anderson

Don't rip ALL the foam out, just enough to go back to the 25 sq.in. and do that 
in steps. You may very well get some benefit from the reshaping, even if 
you can't go all the way to 10 sq.in.

Bill Schertz
KIS Cruiser # 4045

 
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