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Fixed Prop Search



My Velocity fixed gear Elite still needs tail feathers.  I've decided to go
fixed pitch for a first prop - that's pretty firm.  I'm looking for any
suggestions or advice fellow builders/flyers can offer.

Following Fred Carter's dyno proven Vortec V-6 specs, my all alum. Chevy
racing engine should easily deliver 2,800 to 3000 RPMs static to the prop
with 300 Ft. Lbs. of torque.  (Dave Crower - my crank and cam maker - says
his computer dyno shows my engine will deliver even more than Carter's
older design heads and block). The PSRU has a 2 to 1 ratio.  I've narrowed
my search to three prop makers: Prince, Felix and Performance.

Both Prince and Felix want me to go with a two blade, although they will
make the three.  (They assure me the two blade will do just fine).  Given
my 300+ HP, I think three blades will help absorb HP and make for a shorter
prop.  Also, it should be smoother and quieter by avoiding parallel wake
slap.

My decision right now: A wood prop from Performance.  Clark Lydick at
Performance said he won't sell me a two blade because I would not be happy
with it given my HP/torque curves.  And, he suggests the other prop makers
prefer the two blade because it's a lot easier to make.  Clark's price:
$1,950.

Just guessing, he thinks I should start out with a 68" diameter with 74
degrees of pitch.  The widest part of the prop would be approx. 5 to 5.5
inches.

I told Clark my #1 priority is a strong take-off prop, and that I would
accept whatever top end speed it delivers.

I know very little about this subject.  I'm open to any suggestions,
critiques, other prop makers, etc.

Thanks in advance.

Dennis Martin
Velocity 173 FGE