VW Reality

jan olieslagers wrote:

cavalamb himself schreef:

oilsardine wrote:

the modern 'VW engine': http://www.ulpower.com/



Now that is a sweet little motor!


looks good indeed, strange to find such a nice
offer from my own country without ever
hearing about it otherwise...

Only problem - I didn't catch the price?


well, you could check out
http://www.ulpower.com/price.htm
where I read 12400 euro's, ex VAT of course,
but including more accesories than most

That being said, I am intrigued by your
mention of a 500 hrs TBO. Still on their own
website, I read
quote
ULPower has decided not to publish a TBO for our UL260i engine until we
have gained sufficient insight into how a significant number of our
engines are actually holding up to operating in real flying conditions.
/quote

which sounds wise to this beginner's ears

In their download section - the Maintenance Manual.PDF file -
under "Time Limits".

500 Hrs or 8 years.
whichever comes first...

Charles Vincent wrote:

cavalamb himself wrote:

oilsardine wrote:

the modern 'VW engine': http://www.ulpower.com/



Now that is a sweet little motor!

165 pounds
2600 cc
claims 81 HP at 2800 RPM
500 hour TBO
FADEC
No Carb Ice problems

Only problem - I didn't catch the price?


Isn't it more aptly a modern Continental C-85? I think the "modern VW"
as far as homebuilts go is one of the subaru's.

Charles


A lot of people seem to think that about the Suburu, but they weight
quite a bit more than you'd think.

The extra weight means a PSRU is really mandatory to get reasonable
propeller output (HP/LB) - with all the attendent complexity, harmonic,
and weight issues.

In my mind that takes them out of the "modern VW" class.

They seem to be more at home on the nose of RV/Tailwind class airplanes.

Richard

RST Engineering wrote:

Come on, Bob. How do you expect the EAA to make a buck out of something as
useful as this? Sheesh, man, cherchez le dinero.

Jim



Indeed, these things are so simple -- and so fundamental to engines --
that it is difficult to understand why the EAA does NOT endorse a
program of publicly testing engines at its annual convention.




Endorsement would equate to liability.

BEsides, EAA has never really been about the reality of it - they
sell the dream.

Richard

"cavalamb himself" wrote in message
...
Charles Vincent wrote:

cavalamb himself wrote:

oilsardine wrote:

the modern 'VW engine': http://www.ulpower.com/



Now that is a sweet little motor!

165 pounds
2600 cc
claims 81 HP at 2800 RPM
500 hour TBO
FADEC
No Carb Ice problems

Only problem - I didn't catch the price?


Isn't it more aptly a modern Continental C-85? I think the "modern VW"
as far as homebuilts go is one of the subaru's.

Charles


A lot of people seem to think that about the Suburu, but they weight
quite a bit more than you'd think.

The extra weight means a PSRU is really mandatory to get reasonable
propeller output (HP/LB) - with all the attendent complexity, harmonic,
and weight issues.

In my mind that takes them out of the "modern VW" class.

They seem to be more at home on the nose of RV/Tailwind class airplanes.

Richard

A lot of good points, and the radiator plumbing also seems to provide many
happy hours of tinkering for a lot of folks.

Actually, some of the small inline engines, such as those from the Geo/Chevy
Metro, have shown some promise--which was unfortunately mixed with far too
much hype. Actually, it the basic weight is anywhere near as light as was
claimed, then a realistic power rating should work quite well.

Regrettably, I have had no opportunity to weigh any of the engines in
question.

Peter

"Peter Dohm" wrote in message .. .

A lot of good points, and the radiator plumbing also seems to provide many happy hours of tinkering for a lot of
folks.

Actually, some of the small inline engines, such as those from the Geo/Chevy Metro, have shown some promise--which was
unfortunately mixed with far too much hype. Actually, it the basic weight is anywhere near as light as was claimed,
then a realistic power rating should work quite well.

Regrettably, I have had no opportunity to weigh any of the engines in question.

Peter




One of our neighbors is flying a Geo Metro engine in his RagWing Special. Great sound and he loves it, very reliable (so
far!) and simple key start...

"Ernest Christley" wrote in message
...
cavalamb himself wrote:

There was a Neiuport 12 project (two seater) published in Kit Planes a
few years ago. He used a Yamaha engine and transmission - locked in
second gear. (IIRC!)

Real nice article about the airplane and engine.

But no a mumblin' word about how the gearbox cratered a few hours into
the test period.

But, for Pete Sakes! Run a bike at 80% power continuously - in second
gear(!) - what do you expect is going to happen?

TANFL...

George Graham ran a rotary conversion with the stock rotary manual
transmission as a PSRU. It lasted a couple hundred hours before
disintegrating (if I remember correctly).

--
Actually, that makes a lot of sense. Reduction gear problems were explained
to me, there are essentially two causes of uneven wear in a spur gear
transmission; both of which lead to failure. The worse of the two occurs if
the gear ratio allows some the teeth on each gear to transmit power more
frequently than the others--a classic example would be a propeller shaft
turning exactly half the speed of the crank shaft. The slower cause of
uneven wear would occur whenever the driving gear is permanently oriented in
the same relation to the crankshaft so that the same quadrants of the gear
always transmit the power pulses--a condition that is normally avoided by
the clutch, and can presumably be resolved by the installation of a
centrifugal clutch.

I don't personally know how the problem is usually solved in purpose built
PSRU's and the only possibility that I find obvious is that the driving gear
might be harder than the driven gear. That might slow the process, but the
PSRU would still be a major component in calculating the TBO. Perhaps some
here have experience in this area.

Peter

On Feb 6, 8:03 am, Charles Vincent wrote:

Isn't it more aptly a modern Continental C-85? I think the "modern VW"
as far as homebuilts go is one of the subaru's.

Charles

They're not the big solution, either. I installed a Subaru 2.2
litre on a Glastar, using an RAF redrive. The problems I encountered:
-Some vibration at around 1400 engine RPM. Caused by the very light
RAF aluminum flywheel, which doesn't absorb all that much pulsation,
and this interacts with the prop's mass, which has a different
resonance. We had initially used an Ivoprop, and could not balance it
chordwise because the blades would shift a little on the hub bolts.
The subsequent Warp Drive prop was better, but had much narrower chord
and did not pull as well as the Ivo. Further, the Ivo's blades would
flutter if there was too little tension on the torque rods. Scary.

-Burned valves. The engine had a converted Holley two-barrel, with
mixture control that was way too sensitive, to the point that it
either ran or didn't. I modified the valve to get some range. On a
short-field takeoff, usual SOP with an aircraft engine is to lean to
max RPM with the brakes locked and throttle wide open; do that with
the Soob and the valves will burn real quick. The engine has four
valves per cylinder and they're about the size of the valves in a
Briggs and Stratton lawnmower engine. Tiny, with little skinny stems.
Compare them to a Lyc's valves. The 16-valve Soob was designed for
computerized fuel injection, for good reason.

-Couldn't install a mechanical fuel pump in it. No place for one. So,
since you can't rely on gravity feed (the Holley has a small float
valve designed for a 4 to 7 psi fuel pressure) you need an electric
pump. Two of them, just in case. And the ignition is run off the
aircraft's fuel system. So, since (as anyone with car or airplane
mechanical experience knows) 90% of all engine problems are
electrical, it's asking for trouble. Real quiet trouble. Avoiding that
requires another battery and a big diode to protect it, more weight
and complexity and cost and room that isn't there.

-The engine was rated at 130 hp at 5600 RPM. The Glastar was designed
for engines from 125 to 180 hp. Should be good enough, right? It was
OK for takeoff and climb, but for cruise it was lousy. A Lycoming,
redlined at 2700 RPM, is easily cruised at 2500 or even 2600. The
engine is rated for 2700 continuous, if you want that. The Subaru, if
you try to cruise it at an equivalent RPM of, say, 5300 or 5400, will
wear out in no time flat and will burn phenomenal amounts of fuel,
too. And makes the most awesome cabin noise. So you end up cruising at
4700 max, which gives an anemic cruise of 110 mph instead of the 135
that the Lyc 125 would give you. Both engines will give the claimed
143 mph at full RPM, so it's not a propeller pitch issue.

-The exhaust system was two tiny mufflers that did little to contain
the noise. There's no room under the heads, inside the cowl, since the
engine sits low to get the thrust line up where it belongs. I could
hear this airplane 7 miles away. When I flew it, I stayed away from
town.

-The engine compartment was very tight, once the radiator and its
associated baffling was put in. The cooling system was the one thing I
built that worked really well. The cabin heater was the Subaru's
heater core.

-The ultimate cost, in terms of the stupidly complicated engine mount
I had to build and have professionally tigged (17 pieces of tubing and
four special engine brackets), the time I spent, the constant
tinkering, the cowling modifications necessary to make it fit, and the
ultimately much lower resale value it had (half or less than a Lyc-
powered Glastar), it just wasn't worth it.

Dan

wrote:

-The ultimate cost, in terms of the stupidly complicated engine mount
I had to build and have professionally tigged (17 pieces of tubing and
four special engine brackets), the time I spent, the constant
tinkering, the cowling modifications necessary to make it fit, and the
ultimately much lower resale value it had (half or less than a Lyc-
powered Glastar), it just wasn't worth it.

Dan


Dan! You are not going to sell magazines that way...

On Feb 7, 3:42 pm, cavalamb himself wrote:

Dan! You are not going to sell magazines that way...

Good thing I don't rely on magazine sales, huh?

Funny, though. People are always asking me for my opinions on
mechanical stuff. Sometimes they don't like the answers. Sometimes
they want to buy an airplane, so I tell them what to look for and be
aware of and be scared of and that the pretty airplane can clean out
your bank account real fast. They don't like that because they want
that airplane so bad. They buy it and find out I was right. Usually.
I'm supposed to be working on my Hummelbird. That's why I
asked Veeduber about the 1/2 VW, and he says they aren't so good. I
believe that, and have to take it into account. Maybe, if I don't fly
much, it'll be good enough, as long as I expect to be doing the valves
every 50 hours or so. I have been warned, see. I 'm considering
sticking the whole four-cylinder VW on it, like Bruce King did; a
weight penalty, but a little less work expected from each jug.
Sometimes we don't like the opinions of others. We need to
evaluate the source, and if it's experienced in the matter at hand, we
should shut up and listen.
Even if it hurts magazine sales.

Dan

wrote in message
...
On Feb 7, 3:42 pm, cavalamb himself wrote:

Dan! You are not going to sell magazines that way...

Good thing I don't rely on magazine sales, huh?

Funny, though. People are always asking me for my opinions on
mechanical stuff. Sometimes they don't like the answers. Sometimes
they want to buy an airplane, so I tell them what to look for and be
aware of and be scared of and that the pretty airplane can clean out
your bank account real fast. They don't like that because they want
that airplane so bad. They buy it and find out I was right. Usually.
I'm supposed to be working on my Hummelbird. That's why I
asked Veeduber about the 1/2 VW, and he says they aren't so good. I
believe that, and have to take it into account. Maybe, if I don't fly
much, it'll be good enough, as long as I expect to be doing the valves
every 50 hours or so. I have been warned, see. I 'm considering
sticking the whole four-cylinder VW on it, like Bruce King did; a
weight penalty, but a little less work expected from each jug.
Sometimes we don't like the opinions of others. We need to
evaluate the source, and if it's experienced in the matter at hand, we
should shut up and listen.
Even if it hurts magazine sales.

Dan

Dan: Totally agree. Being the Publisher of Experimental Helo magazine I
had to address the problem of publishing ethics vs money. Ethics won out.

Stu