Right now I have three props that I could try on my Corvair. I started with
a grey Prince P-Tip prop 52x50 "thinned". I turn it 3350 static and 3800
full throttle. I runs smooth but fast. In a shallow dive it can go over 4000
- near redline so I am going to try another prop. Tommy Davenport sent me an
older Prince P-tip 52x54 that I tried. Static was 2950 and full was 3330
but there was a lot more vibration. Speeds were only a couple mph slower than
the first prop. I've removed it and sent it back to Prince Aircraft Co. to
have it reshaped and cleaned up. They hope to lighten it and give me a 52x54
that has a static of 3200 and full throttle of 3600. That should give me
best torque advantage without risking overspeed but we will see. The third
prop
is a one front Steve Makish but Im not sure what it is or whether to try it.
Bob Lester has a new generation Prince p-tip carbon prop that is working
well for him and I may have a chance to try it soon to compare RPMs and
Speeds. He says that his top speed went from 150 to 167 - not a bad gain at
all.
We shall see.
As far a props in the prop bank - the VW props can sometimes be drilled
for SAE 1 pattern as well and the SAE 1 for VW pattern. All the props I have
here have both patterns. This would make interchange easier.
As you all know, props are one of those mysterious subjects with so many
variables that make performance predictions difficult. You have to find a
prop that you are happy with. If you get a chance to try various props DO.
That way you have same ariframe, engine and pilot and can more accurately
check prop performance. Get good accurate numbers and log them for others to
gain wisdom from.
Keep building - Sun N Fun around the corner..
Last three weeks my plane has been down for repairs and testing. Repaired
and painted wheel pants and gear fairings, installation of aileron gap seals
(fiberglass strip added to wing edge) 100 hr inspection, new throttle quadrant
and cables, insulating the rear compartment to reduce noise from turtledeck,
nav and strobe light installations, defrost installed, Manifold Pressure
gauge installed, templates for new seat made, and a bunch of cleaning...
Hope to have all finished in a day or so. Im itching for a YYYEEEHHHHAAAA
!!!!!!
N41768 - Bill
