LOP operation

My gripe is with Walter, not GAMI.

Walter is a dentist, and clearly not an engineer. His association with GAMI
was never that of an engineer. He should leave the engineering to George
Braly and the talking to John Deakin.

You also totally missed the point. GAMIjectors are great. They do everything
as advertised. But most of what they do is an answer to a problem that
doesn't exist. I've used them since GAMI serial #19. Engines ran great
before GAMIs however. Twenty years ago Continentals ran easily to TBO. That
is not the case today and a set of GAMIs will not help the longevity of
these poorly built engines at all. Even John Deakin burned out a set of
Continental cylinders in 500 hours LOP in his Bonanza. And their highly
touted fuel savings are, for the most part, due to a decrease in speed. You
know, all that drag increase with V squared.

CHTs are just fine ROP.
Engines run clean enough ROP.
Engine stresses have been doing just fine now for 100 years ROP.
CO is not a problem in maintained exhaust systems.
Airplanes fly faster ROP.
Even the LOP diehards admit engines run smoother ROP.
Gamis have more value in a turbocharged engine.

And, I have plenty of dirt under my nails, thank you for asking.

..
"Tom Sixkiller" wrote in message
news

"kage" wrote in message
...

The engine will burn plenty clean enough ROP.
Stress levels are well within limits ROP
Cylinder temps are well within limits ROP
CO? So what! Goes out the exhaust.

The only advantage to running LOP is an engine that runs at a lower
BSFC.
Which increases range, not so much by decreasing fuel consumption, but
by
slowing the airplane down closer to best range speed.

Walter Atkinson is a dentist. He once told me that my IO-520D was more
like
a Wright 3350 "Cyclone" engine than a O-470U. He is in well over his
head.


Man...10,000 hours on test stands, tons of computer analysis and you know
more than the guys with dirt under their nails. I'm impressed!!!

And your qualifications are, what, again?

I set my engine up LOP and flew it at 2350 RPM which is my normal cruise RPM
at that altitude. Then I set the same RPM 100 degrees ROP. Since this is a
fixed pitch prop and I was in level flight, horsepower was exactly the same.
Airspeed was the same. CHT was 10 - 15 degrees cooler and 25 below where I
usually see it. The engine was rougher but it was not vibration. It was
more like the difference between listening to the upright piano at the
elememtary school play and a Steinway, very noticable if you were focused on
the quality of the sound but not objectionable in the first case.

Although the engine was rougher LOP, when I listened closely, the sound had
a hard to describe quality of "easiness". Combustion actually has to start
while the piston is still compressing. LOP slows the combustion so that
there is less pressure against the piston as it is moving up. Peak
pressures occur at a more favorable point on the down stroke. Perhaps this
accounts for the way LOP sounds if you listen closely.

At anything above 60% power, I would go ROP with my minimal engine
instrumentation but this looks like a great thing to have in your bag of
tricks for hot days or need to maximize fuel reserves without slowing way
down.

We have been leaning aggressively on the ground and about 100 ROP in the
air. Our engine was opened up at 1030 hours due to lifter failure. There
was a normal but impressive amount of crud on the piston tops and exhaust
valves. Anything that reduces that has got to be good for the engine.

Walter can drill on my teeth anytime

--
Roger Long

Howdy!

In article ,
kage wrote:
My gripe is with Walter, not GAMI.

Walter is a dentist, and clearly not an engineer. His association with GAMI
was never that of an engineer. He should leave the engineering to George
Braly and the talking to John Deakin.

You also totally missed the point. GAMIjectors are great. They do everything
as advertised. But most of what they do is an answer to a problem that
doesn't exist. I've used them since GAMI serial #19. Engines ran great
before GAMIs however. Twenty years ago Continentals ran easily to TBO. That
is not the case today and a set of GAMIs will not help the longevity of
these poorly built engines at all. Even John Deakin burned out a set of
Continental cylinders in 500 hours LOP in his Bonanza. And their highly
touted fuel savings are, for the most part, due to a decrease in speed. You
know, all that drag increase with V squared.

What is your agenda? You seem to have an axe to grind, and you get your
facts wrong.

For a given power setting, in general (module altitude effects), there
are two mixture settings to give that power. One ROP, the other LOP.
If you run at, say, 70% power, your airspeed is going to be fixed at
a particular level, assuming stable, level flight. If you run LOP,
you run less fuel through the engine, and you burn all of it up. If
you turn ROP, you use some of it to cool the engine -- using more
fuel than LOP operation. All this for the same speed.


CHTs are just fine ROP.

What CHT level do you think is "just fine"? How does this argue
in favor of ROP?

Engines run clean enough ROP.

On what do you base this unsupported assertion?

Engine stresses have been doing just fine now for 100 years ROP.

Oh? Have you ever examined the operations of round engines,
especially the bigger things like R-3350s? IIRC, LOP operations
were mandatory to get satisfactory performance and engine life.

CO is not a problem in maintained exhaust systems.

What does that have to do with the decision? LOP makes less CO;
isn't that a positive?

Airplanes fly faster ROP.

That claim is especially brown and smelly, given the orifice it
was pulled from. See discussion above. Speed is all about power
levels.

Even the LOP diehards admit engines run smoother ROP.

As opposed to the ROP blowhards who can't abide admitting they might
be wrong? See! I can use cheap rhetorical devices, too! Would you
care to try a logical approach, or are you just interested in being
fanatical?

Gamis have more value in a turbocharged engine.

What does this have to do with deciding to operate LOP? Or are you
just trying to obfuscate with more irrelevancies?

And, I have plenty of dirt under my nails, thank you for asking.

Do you have real qualifications to back up your amazing assertions?
How about real data? Sound logical reasoning?

yours,
Michael


--
Michael and MJ Houghton | Herveus d'Ormonde and Megan O'Donnelly
| White Wolf and the Phoenix
Bowie, MD, USA | Tablet and Inkle bands, and other stuff
| http://www.radix.net/~herveus/

For a given power setting, in general (module altitude effects), there
are two mixture settings to give that power. One ROP, the other LOP.
If you run at, say, 70% power, your airspeed is going to be fixed at
a particular level, assuming stable, level flight. If you run LOP,
you run less fuel through the engine, and you burn all of it up. If
you turn ROP, you use some of it to cool the engine -- using more
fuel than LOP operation. All this for the same speed.

Only at very low altitudes. Get YOUR facts straight. LOP is worthless at
altitude because you simply cannot push enough gas through the engine to
develop any meaningful horsepower, unless, like I said, you are
turbocharged.


What CHT level do you think is "just fine"? How does this argue
in favor of ROP?

For decades we were running ROP and there were no casualties from high CHTs.
I ran several IO520s to overhaul in the 70's without any premature cylinder
pulls.

Engines run clean enough ROP.

Your data is unsupported, not mine. There are, and never were prolems with
Cont/Lyc running "dirty." Where is YOUR data to assert this. You are pulling
this out of thin air. Lack of experience and GAMI propaganda here.

Engine stresses have been doing just fine now for 100 years ROP.

Oh? Have you ever examined the operations of round engines,
especially the bigger things like R-3350s? IIRC, LOP operations
were mandatory to get satisfactory performance and engine life.

So what? We are talking Walter here, GAMI----remember. They don't make
injectors for R-3350s

CO is not a problem in maintained exhaust systems.

What does that have to do with the decision? LOP makes less CO;
isn't that a positive?

No. Not necessarily. Where is your data, as you like to say, that this is
positive? You aren't some tree hugger are you?

Airplanes fly faster ROP.

That claim is especially brown and smelly, given the orifice it
was pulled from. See discussion above. Speed is all about power
levels.

Impossible to pull sufficient power at any reasonable higher altitude
without a turbo. Try running LOP at 10,000 ft. Look at your charts(worthless
LOP) at 10,000 and show me how much power/speed you are making.

Even the LOP diehards admit engines run smoother ROP.

As opposed to the ROP blowhards who can't abide admitting they might
be wrong? See! I can use cheap rhetorical devices, too! Would you
care to try a logical approach, or are you just interested in being
fanatical?

Again you don't even make a point. Smoother is smoother, period.

Gamis have more value in a turbocharged engine.

What does this have to do with deciding to operate LOP? Or are you
just trying to obfuscate with more irrelevancies?

Turbo engines benefit from LOP because they can still pull the necessary
power to run at altitude. You really should get some facts straight about
available power at altitude LOP.

And, I have plenty of dirt under my nails, thank you for asking.

Do you have real qualifications to back up your amazing assertions?
How about real data? Sound logical reasoning?

This is Usenet. You have shown me NO logical reasoning. Only GAMI claims.
Cooler, cleaner, less stress----irrelevant!

Get some experience and check back in.

Howdy!

In article ,
kage demonstrated an amazing lack of reading
comprehension when he/she wrote:


For a given power setting, in general (module altitude effects), there
are two mixture settings to give that power. One ROP, the other LOP.
If you run at, say, 70% power, your airspeed is going to be fixed at
a particular level, assuming stable, level flight. If you run LOP,
you run less fuel through the engine, and you burn all of it up. If
you turn ROP, you use some of it to cool the engine -- using more
fuel than LOP operation. All this for the same speed.

Only at very low altitudes. Get YOUR facts straight. LOP is worthless at
altitude because you simply cannot push enough gas through the engine to
develop any meaningful horsepower, unless, like I said, you are
turbocharged.

You didn't read a thing I wrote, apparently.

If you are running at, say, 70% power, you are spinning your fixed-pitch
prop at a particular RPM. At sufficient altitude, you may not be able to get
70% power, but that is irrelevant to the discussion.

It doesn't matter whether you are LOP or ROP. If you are getting X RPM,
you are getting Y% power. For a constant speed prop, the indicator is
different, but the concept is the same.

Of course, at high power levels, LOP is bad, but usually 75% power and under
is safe (from a detonation perspective).

To effectively operate LOP, you also need better control over the fuel
distribution from cylinder to cylinder -- particularly problematic with
carburetted engines. However, that doesn't change the essential fact that
operating LOP uses less fuel for a given power level than operating ROP.


What CHT level do you think is "just fine"? How does this argue
in favor of ROP?

For decades we were running ROP and there were no casualties from high CHTs.
I ran several IO520s to overhaul in the 70's without any premature cylinder
pulls.

You didn't answer my question, and you left out your assertion that I
responded to. If your engine is capable of running LOP, you can manage
CHTs just fine.

Engines run clean enough ROP.

Your data is unsupported, not mine. There are, and never were prolems with
Cont/Lyc running "dirty." Where is YOUR data to assert this. You are pulling
this out of thin air. Lack of experience and GAMI propaganda here.

Ummm...now you leave out my response and continue with the bald assertions.
You made the claim -- now back it up, unless you are just making stuff up.

Engine stresses have been doing just fine now for 100 years ROP.

Oh? Have you ever examined the operations of round engines,
especially the bigger things like R-3350s? IIRC, LOP operations
were mandatory to get satisfactory performance and engine life.

So what? We are talking Walter here, GAMI----remember. They don't make
injectors for R-3350s

You didn't make that distinction. You simply asserted a century of ROP
operation without distinguishing particular engine types. I, once again,
note that LOP operations were essential to satisfactory operation of
round engines, especially the large ones, and may have been part of
stardard operating practices for other engine types as well. I don't
know all the answers, but I'm not claiming universal use of ROP as the
normal operating regime for all (aircraft) engines for the last century.

CO is not a problem in maintained exhaust systems.

What does that have to do with the decision? LOP makes less CO;
isn't that a positive?

No. Not necessarily. Where is your data, as you like to say, that this is
positive? You aren't some tree hugger are you?

CO is formed when there is more carbon (fuel) than oxygen -- the definition
of a "rich" mixture.

You didn't answer the part about how CO production has any real relation
to deciding whether to operate LOP or ROP. I guess that means you don't
have a reason for including that point in your list -- it was just padding.

Your ad hominem ("tree hugger") further reinforces that conclusion. You
resort to name calling when you can't make a substantive response.

Busted!

Airplanes fly faster ROP.

That claim is especially brown and smelly, given the orifice it
was pulled from. See discussion above. Speed is all about power
levels.

Impossible to pull sufficient power at any reasonable higher altitude
without a turbo. Try running LOP at 10,000 ft. Look at your charts(worthless
LOP) at 10,000 and show me how much power/speed you are making.

Non sequitur. As in, that does not follow. Reread the response to your first
non-point.

Oh, I don't have charts available to me, but somehow I don't think they
really reference the mixture setting when telling you how much power you
can get at a given altitude, or how to get it. If you'd care to provide
a citation that we can all see to the contrary, I'll concede the points
where I am actually mistaken.

Even the LOP diehards admit engines run smoother ROP.

As opposed to the ROP blowhards who can't abide admitting they might
be wrong? See! I can use cheap rhetorical devices, too! Would you
care to try a logical approach, or are you just interested in being
fanatical?

Again you don't even make a point. Smoother is smoother, period.

I made as much of a point as you did, and I even admitted that I was using
cheap rhetorical devices. You just say "did too".

Gamis have more value in a turbocharged engine.

What does this have to do with deciding to operate LOP? Or are you
just trying to obfuscate with more irrelevancies?

Turbo engines benefit from LOP because they can still pull the necessary
power to run at altitude. You really should get some facts straight about
available power at altitude LOP.

What do you mean by "at altitude"? 10,000 feet? 20,000 feet?

I'm pretty sure you can get your normally aspirated light single up to 10k,
for many values of "light single".

And, I have plenty of dirt under my nails, thank you for asking.

Do you have real qualifications to back up your amazing assertions?
How about real data? Sound logical reasoning?

This is Usenet. You have shown me NO logical reasoning. Only GAMI claims.
Cooler, cleaner, less stress----irrelevant!

....and just because it's Usenet doesn't mean you get a free ride when you
make ridiculous claims and don't back them up. You still have not offered
any checkable facts, or any credentials that would tell us why we should
take your word on this.

I have shown (though you clearly ignored it) how more than one mixture
setting can produce the same power level, but you continue to assert
something else. You gave us a laundry list of "reasons" why LOP was a
bad thing but offered no reason for us to take your word for it. When
called on that, you simply continue to repeat, deny, and change the
subject.

Get some experience and check back in.

You first.

yours,
Michael

--
Michael and MJ Houghton | Herveus d'Ormonde and Megan O'Donnelly
| White Wolf and the Phoenix
Bowie, MD, USA | Tablet and Inkle bands, and other stuff
| http://www.radix.net/~herveus/

On Wed, 14 Apr 2004 22:36:41 -0700, "kage"
wrote:

Even John Deakin burned out a set of
Continental cylinders in 500 hours LOP in his Bonanza. And their highly
touted fuel savings are, for the most part, due to a decrease in speed. You
know, all that drag increase with V squared.

I'd hesitate to speak for Mr. Deakin but I'd venture that he'd
disagree violently that running lean of peak burned out his cylinders.
Since running lean of peak results in low temperatures and less gas
being burned, how exactly did they get burned out?

To demonstrate that running lean of peak does not necessarily mean a
lost of power, his "Mixture Magic" column showed a color photo of an
instrument panel of a Cessna 410 running one engine ROP and the other
LOP. Both engines were producing exactly the same power but at
different manifold pressures. The LOP engine was using less fuel and
was running at lower CHT temps. How is that bad?

CHTs are just fine ROP.

Actually they aren't, if you set the engine according to the POH.
Running at 75% or 80% power and set 50 degrees ROP, the CHT's run
above 400 degrees. These are figures that come from Lycoming and
Continental. And yet over 400 degrees is where aluminum begins to
loose strength. Deakin also was able to demonstrate that at certain
POH dictated ROP settings, the cylinders actually distorted from the
heat and began to scuff the pistons. This was during flight testing
with several proprietary probes installed in his engine which could
read what was happening in areas away from the cylinderhead probe.
While these probes were showing alarming increases in heat, the
cylinderhead readings read normal. He had to terminate the testing at
those settings because the readings at the bases of the cylinders were
rapidly rising, indicating that the pistons were beginning to scuff.

Engines run clean enough ROP.
Engine stresses have been doing just fine now for 100 years ROP.
CO is not a problem in maintained exhaust systems.
Airplanes fly faster ROP.

Not necessarily. Same rpm, same airspeed but higher manifold pressure
at the LOP settings equals the same cruise speed. Yes, if you want to
fly at best power, you should be running ROP.

Even the LOP diehards admit engines run smoother ROP.
Gamis have more value in a turbocharged engine.

Once again, not necessarily. Once the GAMI injectors are installed,
Deakin has been able to lean right to the point of having the engine
quit due to a mixture too lean to fire, without any roughness at all.
If there's roughness then the injectors are not matched properly.

Corky Scott

wrote in message
...
On Wed, 14 Apr 2004 22:36:41 -0700, "kage"
wrote:

To demonstrate that running lean of peak does not necessarily mean a
lost of power, his "Mixture Magic" column showed a color photo of an
instrument panel of a Cessna 410 running one engine ROP and the other
LOP. Both engines were producing exactly the same power but at
different manifold pressures. The LOP engine was using less fuel and
was running at lower CHT temps. How is that bad?

Uh, what's a Cessna 410? Is it the predecessor to the 411 with an TCM
GTSIO-520-M engine?

Allen

On Thu, 15 Apr 2004 19:32:39 GMT, "Allen"
wrote:

Uh, what's a Cessna 410? Is it the predecessor to the 411 with an TCM
GTSIO-520-M engine?

Allen

Sorry, working on memory from the article. It was a Cessna 414. See
http://www.avweb.com/news/columns/182084-1.html

Corky Scott

wrote in message
...
On Wed, 14 Apr 2004 22:36:41 -0700, "kage"
wrote:

Even John Deakin burned out a set of
Continental cylinders in 500 hours LOP in his Bonanza. And their highly
touted fuel savings are, for the most part, due to a decrease in speed.
You
know, all that drag increase with V squared.

I'd hesitate to speak for Mr. Deakin but I'd venture that he'd
disagree violently that running lean of peak burned out his cylinders.
Since running lean of peak results in low temperatures and less gas
being burned, how exactly did they get burned out?

I addressed Kage's comments to Deakin and he responded in a private email.
You're completely right that Deakin disagrees...well, vehemently.

If you recall, I said Deakin burned out his cylinders despite his GAMIs, not
because of them. GAMIs will never correct Continentals poor build quality
and crummy warranty service.

All the hype that GAMI puts out about cooler, cleaner, peak pressure etc.
doesn't do a thing for longevity of junk. See Deakin's cylinders, for
example. And if you need to privately discuss this with Deakin, at least get
your "facts" straight. Plus, go get some aviation experience so you can have
something to offer Usenet besides poor manners.

Best,

Get a brain and start using it.
"Tom Sixkiller" wrote in message
...

wrote in message
...
On Wed, 14 Apr 2004 22:36:41 -0700, "kage"
wrote:

Even John Deakin burned out a set of
Continental cylinders in 500 hours LOP in his Bonanza. And their highly
touted fuel savings are, for the most part, due to a decrease in speed.
You
know, all that drag increase with V squared.

I'd hesitate to speak for Mr. Deakin but I'd venture that he'd
disagree violently that running lean of peak burned out his cylinders.
Since running lean of peak results in low temperatures and less gas
being burned, how exactly did they get burned out?

I addressed Kage's comments to Deakin and he responded in a private email.
You're completely right that Deakin disagrees...well, vehemently.