changing props?

[jim]

Hi group,

I am flying an RV-6 with Lyc 0320 160 hp and sensenich fp prop. The performance has been good. I have been thinking about possibly changing props. Why? On long cross country with full load, as fuel burns off cg shifts aft, don't like the handling. Only do occassional long xc tho. I do land at a field which is only 2200 ft with obstructions at one end fairly often (every 2 to 3 weeks in the summer). Home strip is 5,000 ft so it's not a problem. Float at the short strip can be a problem. I am not convinced I need to change props and am just considering options.

I like what I have seen posted about catto 3 blades, but realize that I would be going the wrong way from a W&B and cg standpoint,even with a harmonic dampener, so that's probably out.

If I were to go to the Hartzell CS prop that would be the right direction for weight considerations. I used to have a Cessna 180 and liked the CS prop.
My concern is how much of a hassle is it to convert to constant speed. The engine is ok for cs, how much problem with cowling changes on the 6 would be encountered.

I have not concluded if the $ would be worth it, just considering it.

Is there a lot of change needed to the cowl?

Thanks,

Jim Tambs
RV-6 purchased
building an 8

[db1yg]

Jim,

If you are satisfied with the performance of the Sens and simply need more forward cg why not consider a weighted prop extension and crush plate from a company like Sabre Manufacturing or the flywheel wt system marketed by Landowl (sp?)??? Sure would be cheaper and easier than switching to a cs prop!!

Cheers,

db

[LifeofReiley]

Ditto what Dave said. Easy problem to solve and you can leave some cash in the bank.

[groucho]

Judy Saber makes outstanding prop extensions...hands down the best I've found. So nice that they look like jewelry. She's definitely where to get them from. Not that I don't love my C/S prop...

You can reach her here: http://perfprops.spaces.live.com/

[LifeofReiley]

The Sabre MFG I'm talking about is in Grandbury, Texas

http://www.sabermfg.com/

[db1yg]

I was also referencing Saber Manufacturing in Granbury, Texas. Same company mentioned by Darrell. I have one of their aluminum 4" extensions on my James cowl/RV9a----it is a work of art--almost too pretty to put on an airplane!! For a stock cowl RV you will most probably need the shorter version. Get out your wt and bal info and calculate how much additional wt you would like to have on the nose to get your cg where you want it and Saber can make one up for you!!

Cheers,

db

[Mel]

Originally Posted by db1yg

For a stock cowl RV you will most probably need the shorter version.
Cheers,

db

Depends on the cowling. Earlier F/P cowlings used a 4" extension.

[groucho]

Originally Posted by db1yg

I was also referencing Saber Manufacturing in Granbury, Texas. Same company mentioned by Darrell. I have one of their aluminum 4" extensions on my James cowl/RV9a----it is a work of art--almost too pretty to put on an airplane!!

Weird...it's the same people, but different states, hmmm...search the bottom of Performance Props page & you'll find the www.sabermfg.com link. Wherever they are, get it from them. Not sure if Judy is still making them or if she sold off the business though. I had one of Clark's props & Judy's prop extensions on a previous plane - like db said, almost too nice to hang on a plane.

[RV8iator]

I just finished changing my 8 from fixed to C/S prop. Lot's of work but worth every minute of it.
I had to install a new throttle quadrant, run prop cable, reroute manual trim cable, install governor and pad with the shaft and gear. You have to make sure you have the allen plug in the center of the crank and that there has been no hole drilled in it. You have to have the plug in the crank to pressurize the prop with engine oil.
As for the clearance of the spinner and cowling, I measured mine from the front of the flywheel to the end of the cowl lip and sent that measurement to Whirlwind (I bought a WW200RV) and Greg Anderson specially made me a spinner backing plate to give me the clearance I needed. It fit perfectly.
It was a big job but to me absolutely worth it.
I also had to reweigh the airplane and figure the new CG. This is considered a major mod to the airplane.
I can't begin to describe the difference it makes in the airplane.
I say go for it and put on a C/S...

[jclark]

If you decide to go the CS route, I have all the "kit" needed to make the conversion (prop, governor, cables, etc.) and plan to sell soon as it will not work with the crank we have.

James