Jerry Hey wrote:

    Jerry

That sounds good Jerry. Be sure and make the transition from three inch
round SCAT to the cooler bell shaped.
Here are the coordinates again for the new guys.

Paul Lamar

Jerry,
I don't think that 3" is nearly large enough.  You will probalby need

about 25 sq. in. of intake area (according to Fred Morino) for the oil
cooling.  The 3" is a really small duct.  Take a look at the following
numbers:

3" = 7.069
4" = 12.57
5" = 19.63
5.5" = 23.76
6" = 28.27

FWIW, I'm not flying yet.

Ken P.

Ken Powell
kenpowell@aristotle.net

Ken is right Jerry. I get away with 19 square inch opening and a bell
shaped duct, but at 35 degree C [95 degrees F] ambient I am climb limited 
to 500 fpm.
Ian RV6A

Here is a picture of Ian's setup. I can see a couple of possible improvements.

1. A cowl flap instead of the louvers would would give Ian more control over the
temperatures. The same louver cowl hole could be used for the cowl flap(s). 

2. A lower position for  the oil cooler air scoop would take advantage of the higher 
slipstream velocity further out on the prop radius. Dynamic pressure is proportional 
to the velocity squared so small increases in slipstream velocity result in large 
improvements in dynamic pressure used to force air through the rads.

Paul Lamar

 
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