Ivo Prop on O-320

I have a Lycoming io-360 modified to about 220 HP (high compression pistons,
Ellison throttle body, and electronic ignition on one side). I went looking
for a prop, and talked to someone at Ivo. This was several years ago (5
maybe) but I remember that they wouldn't even sell me one for a direct drive
4 cylinder.

The problem is that saying 220 HP does not tell the whole story. You have to
look at when and how often the torque pulses are generated. The average
torque may be the same, but if you have fewer but BIGGER pulses. A 4
cylinder direct drive has only 2 piston firings per revolution of the prop,
so they have to be BIG suckers to keep the average torque up. That's harder
on the prop. A geared V8 or rotary will give many smaller pulses, and so is
much easier on the prop blade mountings. That's one reason you don't see
many Lyc's with Ivo props.

I ended up with a Warp Drive, and I'm happy with it, but the blade mounting
arrangement is different, and much more secure.Look at how Ivo does it vs
Warp drive, and you'll understand.


Ron Webb




"canflyboy" wrote in message
news
Has anyone have anything to say, good or bad, about the Ivo Prop propeller
for the Lycoming engines? The adjustment feature is quite unique and
interesting, but I'd like to heard from users in the field for their
opinion

Thanks

Canflyboy

I have considered a Warp drive and talked to them about using ts on
my SQ2000 canard with 220 hp Franklin. But they cautioned against it
saying the props were not suited for canard high end performance.
So it really is shoping for the "right" prop for your particular
application.

"Ron Webb" wrote in message ...
I have a Lycoming io-360 modified to about 220 HP (high compression pistons,
................
I ended up with a Warp Drive, and I'm happy with it, but the blade mounting
arrangement is different, and much more secure.Look at how Ivo does it vs
Warp drive, and you'll understand.


Ron Webb

"Paul Lee" wrote in message
om...
But they cautioned against it saying the props were not suited for canard
high end
performance.so it really is shoping for the "right" prop for your
particular application.



There are applications where NO prop is a really good option. A high
horsepower
pusher with the prop in disturbed air is one of those. A small diameter
running at high prop RPM makes it even worse.

A carbon fiber prop has almost no damping. Any cyclical vibrations will just
build and build as energy is input on each cycle and not dissipated.
Eventually a warp drive prop as a pusher in a disturbed airflow (
http://beta.communities.fr.msn.ca/Ad...99668152588100 )
has failed with cracks longitudinally at the tips. That's why wood props are
popular with canards. Energy is dissipated as fast as it's input, so big
vibrations do not build up.

The problem with wood is that (at least in my experience) is not very
efficient. Everyone I know (including myself) who has switched from wood to
carbon has seen a large increase in performance.

Like I said - no good option.

On Thu, 14 Oct 2004 08:30:51 -0800, "Ron Webb"
wrote:

The problem with wood is that (at least in my experience) is not very
efficient. Everyone I know (including myself) who has switched from wood to
carbon has seen a large increase in performance.

Like I said - no good option.

How about a wood prop core, overlaid with carbon fiber? I think
that's what MT does for their props.

Best of both worlds?

Corky Scott

On Thu, 14 Oct 2004 13:28:45 -0400, Corky Scott
wrote:

On Thu, 14 Oct 2004 08:30:51 -0800, "Ron Webb"
wrote:

The problem with wood is that (at least in my experience) is not very
efficient. Everyone I know (including myself) who has switched from wood to
carbon has seen a large increase in performance.

Like I said - no good option.

How about a wood prop core, overlaid with carbon fiber? I think
that's what MT does for their props.

Best of both worlds?

Corky Scott

And in a fixed pitch prop I think prince props are wood and carbon as
well. They also claim to flex a bit to give a quasi constant speed
effect