Well now see? Thats kinda what I am talking about. I have five, a ZDZ 40 single in an Extra, a ZDZ 60 single in an Extra, Two Brisons and one RC Showcase Roto 35, all of which are enclosed in cowls but have either their heads exposed or at the very least an air inlet in front of and equivilant to the size of the cylinder, along with an appropriately sized outlet. Now I am about to put a good sized twin into a good sized cowl and since the air inlets are going to be in front of the cylinders common sense says it should take minimal baffling to make sure the air goes where it should. However, I have been hearing all these horror stories and a few tales of baffling that seems to be awfully elaborate in order to prevent damage to the engine. I have seen some mighty nice engines and planes at flying events and it just never seemed that they got that elaborate with it.