this should be. Max power at 6000 RPM is somewhere around 20 inches
total +/- 3 inches. Port to bell mouth. This is for a 2.17:1 gear box

which

I assume is what you have. Shorter of course for a 2.85:1 box and
7100 RPM.

Paul Lamar

George Lendich wrote:

Paul,
How much shorter  -  is that the total length to the motor, including the
manifold !?

Do you consider that 7,100 RPM to be optimum for take-off using the 2.85:1
ratio gear box - I was thinking in the realm of 7,500 RPM.
George (down under)

Yes. I could be wrong but I think it is directly proportional.

6000/7100 = .84 x 20 inches = 17 inches long +/- 3 inches.

Depends on the prop diameter. Lower diameter.. higher RPM..
more power.. lower prop efficiency during takeoff and climb.
Probably no loss in prop efficiency at top speed.

Paul Lamar
 
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