This is the way I would do it. Louvers in the cowl of course.
Not shown yet. Make a good air racer.
-- 
Paul Lamar ...No rotor no motor.

Hi Paul,
have to confess I love your drawings.

How would you integrate a air scoop in a configuration like this?
As I remember the tubes have to have 20 inches for 7500 RPM.
Could one swing the tubes backwards instead of upside to get the needed length?

Kind regards
Thomas

I was think a ramp slot just above the spinner.
Something like this.