William,

   I am still in the building phase myself but have considered doing the same thing because of the issues you outlined. After visiting Sun-N-Fun this year, I decided not to do it. While looking at Bruce Bohannon' airplane, two mechanics removed the upper cowling. The rear shrouding of the high pressure upper deck had two very large oil coolers (one on each side). I asked the mechanics how this was possible with the demanding cooling needs at high altitude (thin air). They said that the oil coolers actually lowered engine temperature even though high pressure air was being routed away from the engine. They explained that testing had determined that plenty of air was getting in the cowling and was actually backing-up at the inlets. Narrowing of the intake openings was considered but rejected in favor of more oil cooling.

   I am not an expert but what they said made sense in lieu of actual testing on my plane when it finally flies. You might want to try some testing before proceeding with your plan.

 

Mark Quinn

360... 80%