ORIGINAL: Rfabbre
RCPilot: The 1/2 inch lip on your cowl is what I am trying to create. Mine does not have any factory pre-cut holes. Also, the louvers near the bottom rear of your cowl appear to be functional. Did you cut the slots or did they come that way?
Those louvered slots were factory cut. You can't see it real good in the pics, but they are all angled back to create a vacuum.