Prop Time

I am starting to look around for a prop for my 4 o-320 160hp. Any recommendations, performance?

Thanks Guys!

Catto gives good all around performance and is smooth. Sensenich metal gives good cruise performance but has RPM restrictions and can be rough.

That is the only 2 I've run on my -4. I think Smokeyray did a write-up on a bunch of props and it may be worth searching.

Because the -4 is light it seems be forgiving on props. Unless really poorly pitched it will give you near VNE performance at altitude. If I run the **** out of my Catto (3000 RPM) I get VNE down low as well.

getting out some popcorn this could get fun

I have a hartzel constant speed, but truthfully i don't think that i would do it again.

bob burns
N82RB rv-4

The Sensenich carbon fiber ground adjustable is a great prop for an O-320. I love mine. It's incredibly smooth and doesn't suffer from the 2600 rpm limitation of their metal prop for this engine.

Catto for 800 hrs

I have a Catto 3 blade on my -4 with just under 800 hrs on it. 160ish hp with 2 e-mags, Climb is 1200 fpm and I cruise @ 165kts 20 inches mp

I thought I may stir up a hornets nest. All useful info never the less

Hartzel - Bob Burns

Bob (N82RB),
I'd be interested to hear your thoughts on the Hartzel prop? What would you purchase if doing it again? FP?

I found Airmaster Propellers at Oshkosh who has an electric prop setup for Lycoming 150-200 HP. Prop weighs in at 34 lbs, blades are made by Whirlwind. Airmaster has been in business about 15 years specializing in Ultralight, and LSA, and now entering the Lycoming market. I'm very strongly considering this setup for my 4.

Martin was very helpful, and lead time on their props is weeks instead of months. Their website is http://www.airmasterpropellers.com

I'm not connected with Airmaster in any way. It was just one one of the more exciting products I ran across at Oshkosh.

Catto props was / is offering free shipping, a $210 value and $100 off the purchase of a spinner as an OSH summer sale. According to their OSH handout these prices are good through 8/8/15. The price quoted to me for a 2 blade was $2,450 plus $500 if nickel leading edge desired plus $565 if spinner desired. Sale price would make the spinner $465. I have no connection with Catto just offering info I picked up at OSH.

to answer your question, i do like the pros of the constant speed prop.

1. better climb
2.better speed reduction
3. fixes the aft cg problem with a backseater
4. since its metal it polished up real nice.

but the added cost, weight, and maintenance are not really worth it in my option. If I were to do it again i would go with a wood or composite fixed. possibly one of the ground adjustable props. I have heard great thinks about the catto props.

at the airport that I built mine at my friend has a 160 hp rv-4 with a fixed pitch wood prop. mine is 360 c/s. I could get off the ground a lot faster and climb faster but i only had a couple of MPH on him at top end.

bob burns