> > > > Jerry Hey wrote:

 > > > >
 > > > > I just got from Craig Catto's with my new prop.  It is a three
 blade:
 > > > > 68 inch diameter and 80 inch pitch. Originally this prop was
 intended
 > > > > for a 200 hp Velocity but was too much prop and he could not spin
 it,
 > > > > so Craig took it back and hung it on the wall where it waited for me
 > > > > to come along.  I got a very good deal.    Craig asked me if I
 really
 > > > > believed  the rotary could spin this prop and I replied, with plenty
 > > > > of bravado,  that it would make a good "climb" prop.   However, when
 > > > > I bolted it on, a few minutes ago, my confidence was shaken.  Can
 the
 > > > > little rotary really  turn this monster?     Jerry
 > > > >
 > > >
 > > > You will have some clues when you get your engine running Jerry.
 > > > We can also test it on the dyno for static RPM.
 > > >
 > > > Paul Lamar

 > > Jerry
 > > I hope you are going to use a 2.85 drive. If not send the prop. to me in
 > > Australia. I will put it to good use.
 > > Ian. 72 1/2 inch dia. 81 inch pitch. (1 inch + 2.54 real measure.)

 > Is that your current prop dia and pitch Ian? You have a two
 > blade and Jerry's three blade may have more blade area.

 > Jerry will have about 200 to 240 HP at 6000 RPM with
 > a corresponding amount of torque so he may not need
 > a 2.85:1 PSRU. He is building a peripheral port engine.
 >
 > Paul Lamar

 I presume that he has a tractor installation, and can use a pusher prop
 because
 he has the rotation reversal of the 2.15? ratio redrive. Send me the blade
 width
 measurements at .9R, .7R, .5R, and .3R and I will plug it into my prop
 program for some predicted power versus rpm at a couple of speeds. I
 suspect he is going to be bogged down pretty badly at takeoff and slow
 climb. -Vance J.

Vance,   does .9R refer to  the radius at 90% of the blade length?
I just packed  the prop for short term storage but if the offer still
stands a few months from now, I would be appreciate it.   I figure if
a 200 hp Lycoming can turn it, my 220 plus rotary can do the same.
To convert from pusher to tractor, the hub was reversed  by drilling
the dowel holes on the opposite side and filling the old holes.
Jerry

To save time I will answer for Vance. Yes!

Paul Lamar
 
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