Crispeace,
Nice looking plane! An idea on cooling with the cowl on. Looks like your exit air area on the bottom of the cowl is very small. I would suggest increasing that in size to at least twice the inlet air area. Also the inlet air coming in the cowl blisters on the side could just be exiting out the back side of the blister if that is open. You might try to redirect this inlet air down with a couple of diflectors so that the motor is in the cool air blast. Not trying to tell you what to do, just some thoughts. Again, very nice plane.
JEB