Different Engine for Sparrowhawk

[utahgyrocop]

I recently saw a posting about someone using a chev/general motors engine on a gyro. I wanted to get some input of an alternate engine to the Subaro for a sparrowhawk.

Thrust to weight and weight and balance are the two major factors that come to my mind.

Any thoughts or ideas on putting something different for the heart of a sparrowhawk?

The only reason I'm asking is I am going to be restarting the build of mine in the next few weeks and upgrading the engine is a key issue. I have the small subaru and at a minimum want to go to the 2.5 soob, but am always looking for something better.

Thoughts?

Stay safe

[Chuck Roberg]

Hopefully Mike Burton will reply here.

I know his company has tried a couple of different engines as alternates to the Soob. I'm sure he would have some good ideas.

[MichaelBurton]

We had a rotary that we were developing but did not get the power that we were promised. We have gone back to the Soob. At this point we are sticking with that. I dont know of any other engines that have been tried.

2.5 with a cam upgrade.

[jcarleto]

I think he's referring to the 2.2L Chevy Ecotec engine. It is supposed to weigh about the same (297 lbs), and generate similar HP to the 2.5L soob. There was a thread here recently showing a gyro with that engine, but it was not on an enclosed cabin machine. I think that EarthboundMisfit has also looked at the engine.

Here is the thread:

http://www.rotaryforum.com/forum/showthread.php?t=23089

It is an interesting engine, but it doesn't have any gyro history...yet.

[Friendly]

There is not much difference in the top three contenders of the 4 banger inline engines although the Honda has a nice redline
http://www.caranddriver.com/var/ezflow_site/storage/original/application/4c03fc0b437500e32302ac9c054a5264.pdf

[Canadian Rhino]

I still think the 750 cc weber engine used in the Polaris watercraft and snowmobiles would be an excellent choice!
150 HP and half the weight!

[Friendly]

Phil,
If you run across one cheap, email me at mcarmouche2@bellsouth.net .

They're just are not used down here in the hot humid climate of Louisiana.

Cheap, I mean, if steamboats were a dime a dozen, all I could do is run up and down the riverbank and hollar "ain't that cheap!".

[PW_Plack]

Any thoughts or ideas on putting something different for the heart of a sparrowhawk?

Heath, the most promising thing I've seen in a while is the trick Lycoming IO-360 Jim Vanek is putting on the Sport Copter II. Appears to come in at significantly less weight than a Subaru 2.5, with 200+ real horsepower.

The ones he's buying are $20K+ brand new, but a plain, old, run-of-the-mill O-360 or IO-360 sourced on the used market would be about the same weight and slightly more power than most Soob 2.5 conversions, but significantly simpler.

You'd have to devise a new engine mount, but you'd lose the redrive, the radiator, all the electronics...

[swhailes]

Does AirGyro has a SH to train student with yet?

Steve Hailes

[GyroDoug]

Does AirGyro has a SH to train student with yet?

Steve Hailes

Steve,

They sure do!!! They are up and running again and just waiting for more students. Mike is an excellent CFI that I personally recommend him highly.

Heath,

While the Lycoming 360 would get rid of some parts and systems and simplify the installation, it will be more expensive in the first place and you would have to design and build your own installation which is not a job for beginners. There are always new engines being talked about and some of them have lots of potential, but the average new builder would be well advised to stick with something proven like the 2.5 Soob.

I am way excited to hear that you are getting back into the build mode. You'll have to make it to our next chapter meeting and give us an update on how it's going.

[lanichol]

if steamboats were a dime a dozen, all I could do is run up and down the riverbank and hollar "ain't that cheap!".

Haven't heard that expression in years.

[PW_Plack]

...the Lycoming 360...will be more expensive in the first place and you would have to design and build your own installation...

It depends. Used Lycoming O-320s and O-360s with time remaining till overhaul are advertised often in the $6-8K range with all accessories needed to run, and an old-school carb'd O-360 weighs about 300 pounds, like the Soob. There are a couple of companies providing just the dynafocal ring for the mount, which would require an experienced welder to fabricate the attachment to the airframe, similar to what Vance had done on the Predator.

Compared to a Subaru 2.5 in a kit which already provides the ECU, harness, radiator, redrive, etc. for the 2.2, a Lycoming looks expensive. Compared to a Rotax 912/914, maybe not, and an O-360 makes 180 honest HP.

[Earthboundmisft]

Paul, the Lycoming certainly has merit. One is the availability of parts and service wherever you might land. Another is longevity. I have seen Lycs. on airboats tortured for YEARS. The other is aftermarket goodies. One concern is cooling in a pusher config.
Another obstacle as you mentioned is mounting it, merging the dynafocal to the mast.
We recently bought a roached out Comanchee with a 180hp for 3k.

[utahgyrocop]

These are great suggestions and comments. Please keep the ideas coming. My kit (Sparrowhawk 1) has the 2.2 soob. Way to small, especially considering our base elevation led alone density altitudes.

I need to consider a change sooner than later and just want to explore the options that are out there.

Thanks again, keep them coming!

Stay safe.

[rfi]

If someone wants more power than the stock EJ25 they might have the Stratus cam grind done which will boost power to 185-190.

Another option is the EZ30 six cylinder engine. It is less than an inch longer than the EJ25 and develops 212 hp at 5600 rpm. Later models develop 250 hp at 6,000 rpm.

There is also a new 3.5 liter six cylinder engine in the Tribeca SUV which develops 256 hp @ 5600 rpm. I can't imagine anyone needing that much hp except for the lead sled Sparrow Hawk or Sportcopter II.

[PW_Plack]

Don, just so you'll know we're not simply power-mad out here, :) peak summer heat in the Salt Lake Valley leaves us down 25% in HP on a normally-aspirated engine. That's why our fly-in is in June instead of August!

[garybuster]

'79 mazda 12a, significantly bridgeported, intake tuned, carburated, MSD ignition, Ross 2.85:1 PSRU, 4 blade warp drive, 209 lbs engine/ redrive, cavitated thrust test after 815 lbs, dyno'd at 219 hp at 7500 rpm. Hardly ever used full throttle.

[lanichol]

Gary,

Was this on the Mad Max II?

[garybuster]

Hey Hey Larry...

nope... the mad max Easter Egg has a sub 2.2 on it... and the mad max tandem has a sub 2.5... that's why I'm selling it... so instead of replacing the engine, I'll just build another ship around the Mazda!! Besides, I need to build the ship around my own personal physique!! (and I'll build it with training in mind!)

the Easter Egg was a fun ship... just not enough HP to do the heavy passenger trick with the 2.2, the mad max tandem is a GREAT flying ship... just not what my personal needs require!!

IF the East Egg had been driven by the bridgeported 12a, I might have fought MUCH harder in the divorce to keep the silly thing!!! I can ALWAYS build another!!!

Good to hear from you!!!

Gary

[lanichol]

I think you got something there with the Mazda. How about a Sportcopter style mod, axle, tail, to an RAF with a Mazda?