Paul,
I am commited to using the P port configuration and started looking at
specs for props. I do not think a 74" prop will fit on a pusher even
though I have 48" from the ground to the thrustline. I went to your
website where you have two P Ports with different runner lengths. Is
there any advantage running the 2.85 PSRU over the 2.17? The curve on
the higher performance runner looks flat in the range from 6500 to
7800. I think I could swing a 68" prop. Just trying to find the right
combination.
Joe Berki
Limo EZ
Yes. There definitely is a HP advantage. If you can not handle 74
inches think
of a wider blade or 3 bladed prop that will absorb 240 HP of lower
diameter.
Just explain things to the prop builder and he will build a prop
for 240 HP as little as 65 inches in diameter. Could be as many
as four blades if he does not have a wide blade version.
--
Paul Lamar ...No rotor no motor.
With a 2.85 psru and a "small" diameter prop, you are turning the prop
slower than if you had a 2.17, so the tip speeds would be relatively low
- good for noise reduction. To go fast with a "slow" turning prop will
require a lot of pitch, which might tend to stall more at the start of
takeoff roll. But you have lots of power so a prop can be built that
will work. What is max RPM you want to operate the engine?
Perry
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