Bob,

Thanks for the guidance.

Assuming the engine got hot, which I'm certain it did, leads me to ask a few things regarding the 50 Sundowner.  I built a duct from thin balsa to help direct air over the head and it dumps out the back where the cowl cheeks catch up the wing.

Should the exit be enlarged?  On my 42% Kelly F-1 the exit is quite a bit larger than the entrance.  I'm learning a bit more about this negative pressure thing to pull air through the cowl.

On the Jett site where the 50SD is featured the photos/narration don't mention much about cooling.  Any help would be greatly appreciated.

Thanks.

Chad<br type="_moz"/>