Larry DeCamp

Well Known Member
Friend
RV-3 with 0320parrallel mount w/carb,dual Pmag and Catto 2 blade 😞
Would a dynamical 3 blade be worth the effort to upgrade ?????
 
I think he?s asking if it would be worth upgrading from 2 blade to 3 blade. I don?t know what a ?dynamical 3 blade? is.

2 blades or 3, they both work well, if you like your 2 blade I would keep it, if you want a 3 blade get a 3 blade.
 
Sorry

Missed that. But yes, my experience has been that the 3 blades can be a little smoother. Not to start a war. I said CAN be.

:)
 
Mount significance ?

OK, Craig says a 3 blade might be smoother, and of course, balancing can only be worth 0 to plus X? My real unknown is the value of dynafocal. That would require a new mount, new engine and probably a cowl.
 
There is a conical mount upgrade that works better than the standard Lycoming part.

It is Lord mount part J1552. About 5 times the price, but they do make a difference.
 
I don?t know what a ?dynamical 3 blade? is

Must be something like a "jellicle" cat :D
Yeah I know that a 3 blade prop is smoother and lots more sexy looking than a 2 blade, but a 2 blade is slightly more efficient than a 3 blade and a whole lot cheaper to buy.
 
A dynamic prop balance is a lot cheaper than a new prop and has, on mine, made a big difference and that's with a 2-bladed prop. Of course if the dynamic balance wasn't enough and then you got that new prop afterwards, that would be money wasted, I think.

How is the mixture? Any smoothing when you lean or enrichen it?

Dave
 
Larry, the only other thing I wondered about, given the snug RV-3 cowl, is whether the engine is bumping into something.

Dave
 
Ownign both two and three-blade props, I know that they can both be made as smooth as silk with a good dynamic balance. You have several unknowns that, unless you throw money at them, you really don't know how they affect the overall result. Going Dynafocal should help, but it would be a big deal to change. A new prop? Always fun, but unless you have other reasons to change the prop, I think I'd go for a dynamic balance first, and see if that helps.
 
My friend Bruno, who lurks here, has a catto 3 blade on his rv4 and loves the smoothness, but he also had his jugs ported and flow benched at lycon and his crank balanced. And I suspect he had his prop dun balanced as well. He says it runs like a turbine.
 
Dynafocal mount advantages ?

Thanks for the feedback. I will persue your suggestions. Does anyone have first hand experience regarding the advantages of dynafocal vs conical mount ?
Cessna must have done it for a reason !