EJ22 conversion questions.

gyrodrifter

Newbie
Joined
Apr 9, 2009
Messages
146
Location
Bonfield, ON
Aircraft
none
Total Flight Time
90
Hello folks,

Just joined so I could feel at home with the rest of you eccentrics :)

My question is related to going direct drive or if too many negative answers crop up, the conventional re-drive way, belt or gear.

Direct drive is what I want to use if I can get away with it for CLT operation on a Bensen type straight keel machine.
In my limited opinion, it would probably save some weight and would keep things simpler for operation with fewer moving parts to think on and if for no other reason than that I am an eccentric. :D

I also intend to keep in line with the original looks of the Bensen design.

I am studying a few plans for either the Vortech B20, or the B8M styles, liking the Chrome moly tube setup better on the B20, as the overall design strength will be stronger, versus the bolted aluminum way that the B8M uses.

A drop keel is ok if I have to go that route, but I prefer the straight keel.

Reason.. I am a fairly heavy guy at 275 lbs (think of me as Arnie Swartzenegger) and I would want the EJ22 in a detuned condition for durability reasons while being able to keep thrust and HP at an optimum with a two bladed woody, and the machine to be a bit stronger in order to accommodate the changes and weights.

I may have to alter outside of the plan particulars to accommodate my size at 6'3" , the tallness not being as important as the weight considerations.
Ultralight is desirable but is not a must, as I realize I will be teetering on the edge of possibilities.

I also want to do it this way for the preference of the fabrication method being steel tube and welding instead of aluminum square or rectangle and being a bolted construction.
Back to the thrust question, Can anyone expound on that?

Thanks, J.
 
I am not an authority but heres a bit; A prop about the right size can only spin 2200ish as a max rpm,the tips at that speed are approaching the speed of sound. Your motor makes more horsepower if it can go faster.
 
I am not an authority but heres a bit; A prop about the right size can only spin 2200ish as a max rpm,the tips at that speed are approaching the speed of sound. Your motor makes more horsepower if it can go faster.

Groundhog,

Thanks for the reply, I will take that info and check on it.

I was thinking the prop would most likely turn around 3200 or 3600 with a pitch that would allow it to produce the thrust needed.
If 2200 r's is the max I can use for propping then I would have to up the RPM and go to a redrive, which is what I would like to stay away from.

I know that higher rpm is desirable (hence the redrives), and that the EJ22 likes to run around 4500 rpm and up for better results.

I'm guessing that my prop would probably not run more than about a 35-38 inch diameter (keeping the CLT requirements in mind), so in my thinking the rpm would be in the range I suggested, if I am going to stick to the direct drive idea.

Can new cams and pitch make up for the slowdown with that size of prop and rpm suggested?

Any other info or thoughts anyone?

Thanks for the input,

John.
 
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John, I do not wish to deflate your bubble but I may be able to save you some time and expense.
A 35 to 38 inch diameter propeller would probably not develop enough thust to get an EJ 22 machine off the ground, unless it was multi bladed and in a duct fan configuration, and even then I doubt it. If it did fly it would be a very marginal noise generator. Mast and pushrod material is cheap and I think that you would save money by buying a re-drive and a longer, quieter propeller right from the start.
 
Chuckle Chuckle,

Tim....

You are not going to deflate my bubble, because you just made me realize what I wrote down.
With that size prop I'd be lucky to get a bit of cooling on a hot day :D

I know I'm dreaming about keeping in line with the Benson design and using an EJ22 engine to do it with combined with my weight and keep within the ultralight brackets. No way that's going to fly!
I can come up with some mind boggling funnies sometimes when I have 3 or 4things going on in my head at the same time.

Aside of that, I still will persue the bare frame and lawnchair idea but with a lot more info then I have at the moment and also, with a lot more time spent in my old books and course material from the schooling days.
There is also a lot of wisdom in using the advice from the many wiseguys :) on this forum, and that's one thing I can't do without.
I will most likely end up buying a partial kit or project so I can still get it done before I turn to dust.
I appreciate your kind and gentle wakeup call.:D

John.
 
Chuckle Chuckle,

Tim....

You are not going to deflate my bubble, because you just made me realize what I wrote down.
With that size prop I'd be lucky to get a bit of cooling on a hot day :D

I know I'm dreaming about keeping in line with the Benson design and using an EJ22 engine to do it with combined with my weight and keep within the ultralight brackets. No way that's going to fly!
I can come up with some mind boggling funnies sometimes when I have 3 or 4things going on in my head at the same time.

Aside of that, I still will persue the bare frame and lawnchair idea but with a lot more info then I have at the moment and also, with a lot more time spent in my old books and course material from the schooling days.
There is also a lot of wisdom in using the advice from the many wiseguys :) on this forum, and that's one thing I can't do without.
I will most likely end up buying a partial kit or project so I can still get it done before I turn to dust.
I appreciate your kind and gentle wakeup call.:D

John.

Not wanting to deflate your balloon… but do you know what’s involved into converting a Subaru for aircraft use..?

raton
 
I have never flown a direct drive gyro but even just changing gear ratios creates a lot of difference in thrust.
Without a gearbox [preferably a Autofilight] I would consider what you would like to do, a complete waste of time, money and energy.

There is a lot you can do to a Sooby 2.2 to convert it to a gyro engine but my advice is leave the engine alone internally unless its knackered, pull of the pollution stuff, get someone to wire up the original sooby computer and presto, there you go.

Tim McClure can give more detailed explanations in what you have to do.
 
I have never flown a direct drive gyro but even just changing gear ratios creates a lot of difference in thrust.
Without a gearbox [preferably a Autofilight] I would consider what you would like to do, a complete waste of time, money and energy.

There is a lot you can do to a Sooby 2.2 to convert it to a gyro engine but my advice is leave the engine alone internally unless its knackered, pull of the pollution stuff, get someone to wire up the original sooby computer and presto, there you go.

Tim McClure can give more detailed explanations in what you have to do.

***

Thanks for the input Brian,

I have rebuilt a few engines including Continentals and Lycoming all under the authority of the AMO I was working for at the time, but have not specifically modified an automotive engine for aircraft conversion to date.

I am starting to get a little bit of feedback already and that's good from my point of looking at it, as I want to know excactly what I am going to have to do to get where I want to go, direct drive or not.
As for my initial idea/dream....That may never happen, But I intend to build a flying example of what ever that may turn out to be and fly it, and again that's why I am here to find out what's what and where I have to go from here.

I am throwing these questions out for the very reason of compiling what I need to know and what I need to get to for my purpose. The EJ22 engine happens to be one I already have in my collection of things and yes, I was definately going to use that with a basic overhaul of mains and cylinders, and I still may, as I think it is a pertty solid engine.

I appreciate the concern and replies I am getting sofar, and thank you for your input as well, :)
John.
 
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....get someone to wire up the original sooby computer and presto, there you go...

That is already the biggest mistake, many do it because Dick, Tom and Harry have done it, but OM Subaru ECU was never designed for the use in aircraft situation, one of the limiting factors of the Subaru engine is the intake manifold, With this in mind, for a successful conversion one needs a much larger plenum (2.5 times larger than stock), higher air flow capacity (90% over stock) and improved air flow balance between all four cylinders (125% improvement) and with a dedicated Subaru ECU with the added benefit of flexibility of tuning, and broader power range..
raton
 
With the advances in technology (and were you live) you really should look at the yamaha conversion thread that racer put up
charles in st etienne quebec has a beautiful machine (benson style,modified with tall tail) and I know where there is an original benson close to me if you really want that style.Put a yammy on it!!!
 
Not wanting to deflate your balloon… but do you know what’s involved into converting a Subaru for aircraft use..?

raton

***

Raton,

Thanks for your input. The answer is YES I do know what is involved in engine rebuilding in either class, but NOT as in converting an automotive application for aviation use.

My Balloon is made of classified burst proof defensive material and you can't deflate or hurt it without express permission from DHS or the knowledge to do so. :D

I do want to say that I am proud to have so many folks all in the same spot ensuring I get the right cautionary peptalks preps and hints, especially from the KIWI section (You blokes have always been dear to me.)

I assure you THAT has been a very important part of keeping this sport alive for as long as it has, and will do in the future.

I have an EJ22 Soob parked in the yard for the purpose of that very conversion and a machineshop large enough to park a set of transports in to use (We fly RC rotors inside), but perhaps I am fairly stuck on that engine as I love the way it has performed.

However; I am not above getting a more suited or even already built version of any kind of engine to fit my purpose for what is eventually going to be my ride, including the 2strokes.
(Gawd, I dislike the whiney little 2 bangers, had a few with bearing failures and busted cases on the early ones for the challenger U/L's.)

I assure you and anyone else, that I will exhaust all areas for information, and expertise BEFORE trying to accomplish what I have set out to do, YOU are stuck with me!

That's why I had said in an earlier post that I would expect to take my time and not see myself in a machine in the near future.

Thanks for your probe into my personal safety, :D
John.
 
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I'm sorry,I got the impresion you wanted a little lawn chair gyro which would rule out your soob.So now we have a motor.decide 60 or 70 inch prop
 
....get someone to wire up the original sooby computer and presto, there you go...

That is already the biggest mistake, many do it because Dick, Tom and Harry have done it, but OM Subaru ECU was never designed for the use in aircraft situation, one of the limiting factors of the Subaru engine is the intake manifold, With this in mind, for a successful conversion one needs a much larger plenum (2.5 times larger than stock), higher air flow capacity (90% over stock) and improved air flow balance between all four cylinders (125% improvement) and with a dedicated Subaru ECU with the added benefit of flexibility of tuning, and broader power range..
raton

Raton,

This is what I'm looking for, the distinct differences between people who have flown the lawn mowers and the people who have the Technology to say it is a mistake and can cost you!

I am neither for or against either thought process, but rather I will use what info I can gather from this and make my mind up in a more informed manner.
Thanks,
John.
 
I'm sorry,I got the impresion you wanted a little lawn chair gyro which would rule out your soob.So now we have a motor.decide 60 or 70 inch prop

***

Sorry nothing GH, :D

I am open to anything and everything at the moment.

I do have my dreams, but I'm not dumb enough to believe in dragons that do not excist.
Did get your PM just now, Thanks I'll wait for what I asked of you in my answer.

As for dropping in, yes I will ask when the time comes to get by there. Used to park my boat in Penetang harbour :) and drive across the chuck and around the point to go for dinner in Midland, lived on it for three years.
I appreciate the invite.
John.
 
With the advances in technology (and were you live) you really should look at the yamaha conversion thread that racer put up
charles in st etienne quebec has a beautiful machine (benson style,modified with tall tail) and I know where there is an original benson close to me if you really want that style.Put a yammy on it!!!

***

GH,

I would like to be able to try all of the possibilities of powerplants and get my hands on in each conversion and build, Unfortunately I am not able to do the buying of all of the various engines anymore due to financial shortcomings at the moment.
I can forsee buying a low mile 3 cyl Geo engine that's available to me at a very reasonable price as an alternative to the soob weight issue and with doing the build myself, but not if I can go the soob build and put an airworthy machine in the air. The dream was just that, a dream. Reality dictates future activity.
The way things look from here at this point in time, I may not be able to go fast for a good while to come at any rate.

So...The slow way is just as good as far as I'm concerned, It gives me time to really get in to feasibility and research on things before I commit.

I will do as much as I can to end up with the most feasable and economical setup as I can manage, dreams or no.
I have more time on hand than finances can support at the moment, plus I am dealing with a boat and a house refurb at the same time :D.

If I can, I still want to use the Soob based idea although it may not be on a Benson wired afair.
It is too early along in the game to be making solid decisions on what how and when, but I AM interested in the info that you sent me via PM.
Please read my reply and answer if you like.
John.
 
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With the advances in technology (and were you live) you really should look at the yamaha conversion thread that racer put up
charles in st etienne quebec has a beautiful machine (benson style,modified with tall tail) and I know where there is an original benson close to me if you really want that style.Put a yammy on it!!!

With the advances in technology..

I would hardly call a carburetted (Yamaha) engine a technological advancement.

raton
 
Rat are you trying to piss people off or does it just come natural?
 
Rat are you trying to piss people off or does it just come natural?

No…not at all, but isn’t this board to exchange ideas and opinions.. or must I agree with everything dished out here..? Is the Yamaha a nice engine, yes, but being a carbureted engine and not FI, in my opinion is not technological advancement ...

raton
 
Although ratons the expert,the sled-heads around here are truly impressed with the barometric conversion and this engines ability to run for hours at wide open throttle from georgian bay to parry sound and back.one has 82000 kms of hard driving and keeps going just to see what this machine will take.No other machine comes close,once the've proven there is no pressure cracks they tend to run wide open all day.
I believe he runs the 1000 cc fi motor though.His only problem to date is that since the track(at these speeds) wants to go round or balloon the studs are ripping the bottom out of his seat
 
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