any tips on cleaning out the cowl?

what about any noticible cahnges in engine performence while runing ac, i ask because it seems to me it would deprive the engine of air while the AC is runing, right? doesn't the cowl feed the ac ventilation system?

In the south only run recycle a/c, which means that no outside air is induced, only recirculates inside air. even when cruising and wanted to run with outside air and a/c do not see a problem because of low throttle needed for cruise. Added a throttle switch for over 3/4 throttle to cut the a/c for my car.