***A sincere thank you Walter, i am in the process of modifying the engine cowl of my aircraft, and have heard during the APS course of the cooling misconceptions, now you have inspired my to get the gopro out, some wire and tuffs, to do some testing on my own aircraft before i start rehaping, or moving cooling air inlets to the rear to take advantage of the stagnet air(higher pressure) in front of the windscreen, considering the new prop and spinner combination now covers most of the original front inlet, leaving only approx 2 inch gap either side of the spinner. my theory is to close off the nose inlets completly, and move the intake to the upper rear of the cowl, and direct the cooling air forward with internal ducting to above the cylinder heads, and continue down to the lower deck and out the convnetional manner. as for cooling on the ground, the engine is partially fluid cooled and oil cooled.***
WAIT, you may be pretty well off as it is. Ever look at the inlet on a Hurricane?
I'd collect some data before changing anything and collect data AFTER the changes. Otherwise, you have no way to know.