Basically the airflow wants to come in straight from the front of

the airplane.
One of the 90 degree bends is because of that. The other is from the
throttle
body to the runner which not much can be done about.

If you align the throttle body in aircraft longitudinal axis and provide
a properly
designed scoop you can fully benefit from the dynamic pressure at 200
MPH.
Ideally speaking dynamic pressure at 200 MPH  is 104 pounds per square
foot or about .722 psi. 29 inches of mercury is about 15 psi or about
2.4
percent more power. Perhaps as much as 5 hp. No air filter as there
would
be a pressure drop across that. Knowing the air consumption of the
engine
at 200 HP or so you can size the scoop for minimum loss at say top
speed. A small point perhaps but every little bit helps.

Paul Lamar

alventures wrote:

One thing, though, about sizing that ram scoop for effective use of some
dynamic pressure @ 200 mph; that scoop is quite a restriction and a very
inefficient entrance when at 20 mph and WOT staring your takeoff roll.
It seems you need a secondary entrance that closes when the pressure in
the intake plenum is higher than static pressure.

That's an issue I'm wondering about because I have such a intake scoop,
and currently no backup inlet for very low speeds. (See attached pic,
scoop above strake (wing removed), behind rear window at leading edge of
engine cowling.)

Al

No pic came across Al.

Paul Lamar
 
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