Just talking about VWs

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Pops

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The great thing, if this is your objective, is that you don't need to worry about liquid-cooled heads, about polishing/porting, about spray bars, or even fat fins. The road to a reliable 65HP VW-based aero engine is a well-traveled one, and requires nothing more than standard parts (brands and styles proven to work in airplanes), standard assembly methods, good workmanship, and attention to the cooling airflow (nothing fancy, but very few leaks, good pressure drop from intake to exit, and keeping the air tight and flowing well over the hottest parts of the engine). Folks who do all those things and don't ask for more than 65HP (a MP gauge is your friend), seldom have cooling issues with VW-based aero engines.



Very well said.
 

blane.c

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I am interested in knowing more about installing the prop on the flywheel end is there more than one method? It seems that driving from the flywheel end is lighter? Do you just put the nose cowling around the engine case or do you build a prop flange to stick out a ways? Are there ways to get more bearing surface around the #1 bearing or it is ok for the prop loads as it is? And what happens to the #4 bearing when the prop is put on the other end, I suppose it is just driving a pulley again but?
 

blane.c

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Anybody else a little skeptical of 75hp from a 1300cc 1/2VW that hasn't run yet?
I am curious of the price, it is usually commensurate with hp. and there is no mention of price anywhere I can see which is indicative of "if you have to ask you can't afford it"?
 

Pops

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I am interested in knowing more about installing the prop on the flywheel end is there more than one method? It seems that driving from the flywheel end is lighter? Do you just put the nose cowling around the engine case or do you build a prop flange to stick out a ways? Are there ways to get more bearing surface around the #1 bearing or it is ok for the prop loads as it is? And what happens to the #4 bearing when the prop is put on the other end, I suppose it is just driving a pulley again but?
When VW's were first used on airplanes driving the prop on the flywheel end was the normal way, then when the VP-1 can out being dirt simple with the prop driven off the pulley end, that way became the normal way to drive the prop. Worked OK on the little 36 and 40 HP engines with the lighter load. But when people started wanting more HP and putting more load on the small end of the crank and the small #4 bearing and crank problems started to develop. Then came GP's Force One #4 bearing mod that was somewhat copied by other people. The large #1 bearing seems to be holding up the the prop loads of the larger displacement VW engines at this time but the flywheel drive is not used as much as the pulley end Yet. At this time GP's sells the parts for a flywheel drive with a 5" extension and if you want an auto transmission type flex plate flywheel to support the starter ring gear for electric start. At this time there is one problem using the flywheel drive, no one makes a mag drive for the pulley end. So you are forced to try to use the very large, expensive, not that long lasting Vertex mag that plugs in the distributor hole in the top of the case, or used a car distributor or an electronic ignition that requires an electrical system with the increased weight. When using a flywheel drive engine you put a stock or one of the after market different dia pulleys on the pulley end and if desired, use it to drive an alternator for a electrical system. Have to use a pulley with the built end oil singer acting like a oil seal to keep from having one large oil leak.
I have some parts machined for a pulley end flywheel drive for my 2180 cc Flywheel drive engine. Just need time to get back to work on it.
 

don january

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When VW's were first used on airplanes driving the prop on the flywheel end was the normal way, then when the VP-1 can out being dirt simple with the prop driven off the pulley end, that way became the normal way to drive the prop. Worked OK on the little 36 and 40 HP engines with the lighter load. But when people started wanting more HP and putting more load on the small end of the crank and the small #4 bearing and crank problems started to develop. Then came GP's Force One #4 bearing mod that was somewhat copied by other people. The large #1 bearing seems to be holding up the the prop loads of the larger displacement VW engines at this time but the flywheel drive is not used as much as the pulley end Yet. At this time GP's sells the parts for a flywheel drive with a 5" extension and if you want an auto transmission type flex plate flywheel to support the starter ring gear for electric start. At this time there is one problem using the flywheel drive, no one makes a mag drive for the pulley end. So you are forced to try to use the very large, expensive, not that long lasting Vertex mag that plugs in the distributor hole in the top of the case, or used a car distributor or an electronic ignition that requires an electrical system with the increased weight. When using a flywheel drive engine you put a stock or one of the after market different dia pulleys on the pulley end and if desired, use it to drive an alternator for a electrical system. Have to use a pulley with the built end oil singer acting like a oil seal to keep from having one large oil leak.
I have some parts machined for a pulley end flywheel drive for my 2180 cc Flywheel drive engine. Just need time to get back to work on it.
Pops I hope your machining at least 2 samples of the mods for your 2180 cc FLY DRIVE ENG. Hint hint.:) I'd like to hear more about you endeavor. I'm starting to see on my T-mono I may have to go with the small end of the engine up front because of my cowling style and size.
 

Pops

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Pops I hope your machining at least 2 samples of the mods for your 2180 cc FLY DRIVE ENG. Hint hint.:) I'd like to hear more about you endeavor. I'm starting to see on my T-mono I may have to go with the small end of the engine up front because of my cowling style and size.
The large transaxle flange around the flywheel end of the engine can be cut off quite a bit for a small size.
 

Marc W

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I would like to hear more about your prop spacer if you care to share those details. I thought you said somewhere else that you are using a cut down flywheel for a prop hub. How does the prop hub and the spacer fit together?

I would like to shed some weight from my plane and one option is to ditch the electrical system and use a flywheel drive engine.
 

wanttobuild

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Pops

Why do you add a link to a broken crankshaft ad?

Go ahead and say what you wanna say.
>Moderator Edit<
H-Minus
 
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Pops

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Pops

Why do you add a link to a broken crankshaft ad?

Go ahead and say what you wanna say.
Why be a prick about it?
H-Minus
When someone is trying to start a business, I would rather have him succeed or fail on his own merits.
But, looks like on the 4 cylinder he is using a sunk fit prop hub and the small #4 main bearing for support of all the loads on the crank. What do I know, I'm just looking at a picture. He has the facts. OK up to 1915 cc and a light wood prop. Not a 70+ Hp stroker engine. If he thinks he can make it work.............. I really hope he does.
 
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don january

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The large transaxle flange around the flywheel end of the engine can be cut off quite a bit for a small size.
I have about a 13"width x 21" height to work with inside the cowling. the width is going to be the touchy part not so much with the cylinders and heads because of the cheek's but mainly up front to fit the Trans. mount area I don't know how narrow I can get the engine down to and still have the hard points for mounting. I do plan on utilizing a bed mount configuration.
 

Pops

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I would like to hear more about your prop spacer if you care to share those details. I thought you said somewhere else that you are using a cut down flywheel for a prop hub. How does the prop hub and the spacer fit together?

I would like to shed some weight from my plane and one option is to ditch the electrical system and use a flywheel drive engine.
Cut the center out of a flywheel that is used for your engine ( not all the same). Lay out mounting bolt holes to match the layout you used on the prop hub or like the spacing on the flywheel drive prop hub that GP's sells if you don't want to machine your own.
For VW engine college read everything that the late Bob Hoover wrote. Bob published drawing for everything.
http://bobhooversblog.blogspot.com/2007/06/av-prop-hubs.html
 

Vigilant1

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I feel very fortunate that we are (still) allowed to experiment in "experimental" aviation. People can still risk their butt trying a new idea. With VWs, the parts are inexpensive and the engine is simple, so people try a lot of things.
On another point, one of the great things about flying VWs is that thousands of people have already done it, and we know what works. A lot of forced landings and depleted bank accounts helped build that knowledge.
A builder can choose to take full advantage of what has been learned in the real world, or try to blaze a new path.
There's no honor in being the second, or seventieth, person to make the same avoidable mistake.
I do think anyone selling an engine with a totally new configuration should fly behind it himself/herself for a few hundred hours before selling it to customers.
 
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don january

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Pops

Why do you add a link to a broken crankshaft ad?

Go ahead and say what you wanna say.
Why be a prick about it?
H-Minus
I think the info from GPAS is very good reading and allows persons who wantobuild a plane with the intent to run a VW engine in any configuration a place to learn of defects found in their scope of research.
 

Pops

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I feel very fortunate that we are (still) allowed to experiment in "experimental" aviation. People can still risk their butt trying a new idea. With VWs, the parts are inexpensive and the engine is simple, so people try a lot of things.
On another point, one of the great things about flying VWs is that thousands of people have already done it, and we know what works. A lot of forced landings and depleted bank accounts helped build that knowledge.
A builder can choose to take full advantage of what has been learned in the real world, or try to blaze a new path.
There's no honor in being the second, or seventieth, person to make the same avoidable mistake.
I do think anyone selling an engine with a totally new configuration should fly behind it himself/herself for a few hundred hours before selling it to customers.
Same for a new design like my JMR Special.
 
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