RV4 propeller information.

[Sanch627]

Thinking about getting a prop made from Culvar Props,
some of information they need to carve one is the cruse RPM and MPH, Max RPM and MPH, I going to be putting it on a O320 D2G 160 hp, I know what Vans states for mph, any comments, I might jus be over thinking this. A pitch between cruse and climb is what I?m looking for.

[Christopher Murphy]

Go for best cruise performance. Unless you fly off of a really short strip you dont need a climb prop. You will just be waisting capability.

Cm

[cubdriver]

Suggest you consider Catto before making a final decision. They make awesome props.

[brad walton]

My Van's RV 8 construction manual, which dates from the last century, has a discussion about fixed pitch "cruise" vs "climb" props which explains why the climb prop will out perform the cruise prop in most regimens. I suspect the reason some people are disappointed by their props performance is because they choose cruise over climb. Although it may seem counterintuitive to some, you will get more speed and better climb from a prop that can take full advantage of higher rpms.
I asked Craig Catto to give me a prop that would hit Van's advertised 75% power cruise speed. At 8000 ft density altitude and 2700 rpm (75% power) I get exactly what Van used to advertise for a 180 hp RV 8, which was 204 mph. But I also get decent economy cruise and a good rate of climb. Don't be fooled by the "cruise" prop myth.

[Christopher Murphy]

You told Catto to build a prop that gives you the performance you wanted in cruise. I dont like the terms cruise or climb prop. I prefer under or over pitched. Of course, there is more involved than pitch too

I had a catto prop. It was a beautiful work of art and was under pitched to allow higher RPM and was very fast , but at normal cruise power and RPM it was not nearly as efficient as the Sensenich GA prop or the Metal prop I also experimented with.

If you can over speed your prop at your target altitude you are leaving performance on the table. I dont know what a 2 blade catto cost now but id save up a few more dollars and go with the the Sensi GA prop. Its the last prop that will be on my -4 while I own it. The only downside is that its very light.

Cm

[Scott Hersha]

I have a Sensenich GA prop on order for my RV4. A two blade Catto was about $300 less (2950), and a three blade Catto was about $300 more ($3700) than my two blade Sensi GA. There is a 3-4 week lead time with the Sensi, and a 3-4 month lead time with the Catto. If you want a metal Sensenich, I?ll be selling mine pretty soon. Included will be the 2.25? spacer, and metal Sensenich spinner all in very good condition.

[Sam Buchanan]

Originally Posted by Sanch627

Thinking about getting a prop made from Culvar Props,
some of information they need to carve one is the cruse RPM and MPH, Max RPM and MPH, I going to be putting it on a O320 D2G 160 hp, I know what Vans states for mph, any comments, I might jus be over thinking this. A pitch between cruse and climb is what I’m looking for.

I have no experience with a Culver on an RV but can tell you the Culver on my biplane is a work of art. Alaina really knows how to carve a prop at a reasonable price and once you provide her with your numbers she should be able to provide a prop that performs as you expect. She makes props for everything from ultralights to huge WWI replicas and has a wide customer base.

The vids of Alaina carving props are fascinating to watch:

https://www.youtube.com/c/CulverProps/videos

[SJordan]

I have a 3 blade Catto on my -4 and can’t be happier. I fly Formation, aerobatics, long cross country’s and even raced Reno all with the same prop from Catto. They make amazing props and there customer service is amazing. There is a reason they have a wait time!