Helicopter engine for RV-7 ?

I know this question has been asked before, but they were older post. I have the chance to buy a Lycoming HIO-360B1A engine from a helicopter. I was told that you can use this engine, but the cam shaft needed to be replaced because of the difference in RPMs used. I was also told that the engine mounts differently from that of an airplane engine and that it wouldn't work. Can someone point me in the right direction?

Thanks,

John

Hi John,
I can't answer your technical question about the cam shaft but I can tell you about my experience with that exact same HIO-360B1A installed in a glassair 1 I flew.
If you look at the book numbers, it develops 180 HP at 2900 RPMs. If you look at what it's developing at 2700 it's only around 160 HP. You now have the equivalent HP as a 320 Lycoming but the weight of the 360.

My 2 cents, not worth it!

?

It is a lot of trouble to make that engine fit. You will need to change the sump.
Reroute / re plumb the FI. Pretty sure it is a conical mount. That can be fixed too.

If it is cheap enough? It might be worth getting. I have done one of these for an RV. If you pass let me know the price , times and contact number. I might want it.

johnpstoll said:

...I have the chance to buy a Lycoming HIO-360B1A engine from a helicopter...

Click to expand...

<pedant mode=on> Will the helicopter give you a bill of sale with the engine? </pedant>

Flyfish said:

Hi John,
I can't answer your technical question about the cam shaft but I can tell you about my experience with that exact same HIO-360B1A installed in a glassair 1 I flew.
If you look at the book numbers, it develops 180 HP at 2900 RPMs. If you look at what it's developing at 2700 it's only around 160 HP. You now have the equivalent HP as a 320 Lycoming but the weight of the 360.

My 2 cents, not worth it!

Click to expand...

Can't you just pitch the prop to run at 2900 rpm? That's what it's designed to run at.

Be careful of the OWT factor at play here. Many (most) of the "helicopter" engines have the exact same internals as their "airplane" counterparts. Yes, the sumps, magneto drive gears and mounts are sometimes slightly different, but those are typically easily rectified. And often times the only difference is in the numbers stamped in the data plate. The RV-8 in my hangar has a 200 HP HIO 360 installed and I'll bet there are only a very few people who could ever tell if they didn't look at the data plate. I also have a 180 HIO on my Pacer clone and it is identical to the standard old -B1E found on a Cherokee except for the conical mount (and the cushion drive on the mags). Also have a buddy with a 200 HP HIO that has a strange sump (easily changed), and the Dynafocal 2 mount angle - which Van offers a mount for - other than that, no issue.

Do your homework, check the part numbers, and buy it if it meets requirements. Simple as that.

Helicopter engines rate the power differently.
My RV-8 has an IVO-360A1A, converted. It's rated at 180 HP @ 2900 rpm at 1500 feet above sea level IIRC. Power loss with altitude could be the difference, also SAE rated horsepower can be 5% low, so an aircraft engine rated 180 HP can be delivered to the customer if it only puts out 171 HP.
Horsepower to a helicopter is a more profound factor so i think horsepower ratings are more carefully and accurately described. you can see the similarity if you compare operating manuals.
My vertical engine conversion required a gear case, a magneto idler gear, and a sump. I went with a Superior aluminum cold air sump, the were $1300 at the time, lighter weight and better price.
The Bendix 200 mags were re-used. The Bendix fuel injection was missing parts, so I don't know how re-usable it was, I went with Airflow Performance injection and didn't look back.
Vans provided the conical engine mount, it was built by Bruce MacIntyre in his fabrication shop in Tacoma WA.
I bought VANs cooling baffle kit. Helicopter engines need aircraft baffles. add that consideration, also it takes a few days work to assemble.
An interesting difference, there is an oil tube from the crankcase oil gallery along the tappets to the head of each cylinder. they circulate oil around the exhaust guides and dump into the rocker box. I run with cool head temperatures. Seeing this when I bought the engine, I went with the 10 row experimental aircraft oil cooler.
I'm totally satisfied.

I have an HIO-360-A1F6D variant in my 7, the hardest part for me was sourcing the straight thread O-ring oil cooler line fittings instead of the standard NPT fittings. It took more work and head scratching but I'm still $$ ahead.

I purchased an O 320 B2C out of an R22 helicopter

? purchased an R22 helicopter engine that had a rotor strike while in auto rotation. Autorotation requires the engine be disconnected from the engine.

The price was right at 4500 Cdn with everything on it started,, carb, alternator etc. And 300 hrs certified nleft to go.

The sump needed changing, cam gear, renewed carb, mags, fully inspected and painted plus more for 5K Cdn more.

These have been used often in RV 7 like mine and can be a good find.

Good luck

49clipper

No problem at all when I put an HO-360-B1B in my acro sport biplane. I flew it for ten years and many hours with not an once of problems. I rebuilt before installing though, and had the cam reground to produce 180hp at 2750. Other than that it was stock and a very strong and good engine. (The H stands for horizontal (not helicopter) and just means it was mounted just like aircraft engines)