Bh5 io-550?

[Grum.man]

I've seen it mentioned in past post but was curious if this would be a good fit for the BH5? I have one and as you know there aren't many kit planes that are designed around them. After seeing the BH5 at Oshkosh it really caught my attention especially knowing it can handle the power. I've see on the Mark's site they offer an O-470 mount, think they will develop a 550 one?

[rodsmith]

I would first try to get a good installed weight on the IO-550 and compare it with the IO-580. Continentals seem to be heavier. If it seems reasonable call Mark and express your interest. I imagine Mark would need to have at least a few people interested before committing to tooling for another engine mount.

[Grum.man]

I would first try to get a good installed weight on the IO-550 and compare it with the IO-580. Continentals seem to be heavier. If it seems reasonable call Mark and express your interest. I imagine Mark would need to have at least a few people interested before committing to tooling for another engine mount.

Looks to be about a 50lb increase over the 580 but the weight of the 550 includes an oil cooler where as the 580 does not. Thanks for the suggestion.

[whee]

Can’t compare TCDS weights directly between Lycoming and Continental. There is stuff Lyc doesn’t include. I posted somewhere about it several years ago so the info is out there but I can’t remember.

A 550 would be killer on a BH5 for a variety of reasons. It’s too bad Continental has the horrible starter adapter on their engines but for some the other positives make it worth deal with. Plus, since no kit planes use them the demand is low and engines are “cheap.”

Get in touch with Mark and see if he’ll do it. I’d wager chances are nil but you never know.

[Grum.man]

I sent Mark a PM. My main desire is the fact that I already have an IO-550-N that's currently flying on another airplane.

[Battson]

I would suggest shortening the engine mount a little bit to account for the heavier engine. There is plenty of room.
Just an inch or two would make a huge difference, but you would need an accurate picture of the finished weight of a -550 to get the distance and the balance right.

[Bcone1381]

I asked one person in the Bearhawk Booth about installing a Continental for the 5 at OSH this year. (for the same reason you sight....availability and value) The concern was a question about it fitting under the cowl.....saying that it is unknown and the Continental's space requirements are different than Lycoming. (focus was only on the uncertainty of its fit rather than something else like weight, or reliability)

To me and my limited experience I wonder if it means a different non-traditional homebuilders nose bowl might be required. We are experimenters! If thats all there is to accommodating a Continental then it might really open up possibilities for others.

[Grum.man]

I'll be honest, the 550 seems more compact overall and a lot easier to package. No starter flywheel, shallow sump, no need for a separate air intake.

[zkelley2]

How different is the 550 mount from a 470?

[whee]

Bob is pretty awesome at helping builders do custom stuff so he’d almost certainly help design the mount. Building it wouldn’t be hard.

You could get him an accurate FWF weight by removing the mount bolts in your current plane and hoisting the engine just enough to lift it off the mount. With this info Bob could determine if the engine needs to be moved aft.

Maybe noteworthy: I looked at installing a 550 and a 520 on my 4-place. I called a commercial operator I trust and asked his option. The gist was if your going to run the engine in their normal power range, which means 12-16gph for a 550 or 520, then either engine is great but the 550 is awesome. If your going to spend a lot of time loafing around at low power then both engines would be quite unhappy.

[Grum.man]

I'd be curious to know why he thinks that. I routinely run my 550 at 15" 2400 and it is happy as a clam. That nets around 8-8.5 gph lean of peak.

[whee]

His explanation was thorough but I can’t recall the details. Something about the intake design causes mixture differences between cylinders at low manifold pressures. He flies and maintains a number 520/550 for his business so I trust what he tells me. However, I missed that yours is a N which has cross flow cylinders. Low power settings likely aren’t a problem there because of the tuned intake manifold. It will be a challenge to fit it under the cowl but would be worth it IMO.

[FFTravism]

Hate to resurrect an old post but was anything figured out on using a IO-550? I might have access to a reasonable priced 550.
Travis