On Fri, 12 Oct 2012 21:42:13 -0400, wrote:

On Fri, 12 Oct 2012 12:13:21 -0500, Richard
wrote:

On 10/12/2012 12:10 PM, Richard wrote:
On 10/12/2012 7:59 AM, Existential Angst wrote:
Awl --

Would seem like a no-brainer, but goddamm, it shore has me beat!

Yeah, I know, pull the fuse!! Yeah, I know, the fuse labeled
"alternator".....

But when I did that, the alternator light or battery lite would not
come on.
AND, iirc, I DID check the voltage at the battery, to see if it went down
to 12, or was up at the ususal 13-14, and indeed, it stayed at 13-14,
indicating a working alternator.

And the engine compartment is so g-d crowded/complicated, I can hardly
tell
a wire from a hydraulic line, so it's not easy to even find the right
wire.
I figger at 100 A, the wire would have to be perty thick....

The reason for disconnecting the alternator is this:
On an old mazda 929S, the alternator went -- and I could StoG that my mpg
jumped by 15%.... would like to re-examine this phenom with my ScanGauge,
to see if it is real.

If this is indeed a true phenom, I could wangle myself a bit of a
hybrid by
just keeping a spare batt in the car, and switch in the alternator
when the
first batt dies. But basically try to do all the batt. charging at home.

Altho, there proly is no free lunch: I'll proly use my gas savings to
buy a
new battery every year?? LOL
But the actual tradeoff would be inneresting to see.

15% seems a bit high for a high MPG car, but maybe.

The alternator does take a considerable amount of power to turn.

But I'm afraid that the


Sorry - hit the wrong button.

Without the alternator your battery will not run the car for very long
at all. Solid state ignition takes power.

And you will not get much life from the battery either if you pull it
much below 50% very often.

What you want is a magneto.



Or like on an airplane - TWO magnetos. Then you still need to power
the injection - which takes more power than the ignition. And wait - a
magneto IS really just an alternator or generator - and it takes power
as well.

Nope. A magneto is self contained and requires no outside source of
power.
--
Cheers,
John B.

"John B." wrote:

Nope. A magneto is self contained and requires no outside source of
power.


BS. It would have to be 'Perpetual Motion' if you were correct.
They are permanent magnet and convert motion to electricity, until the
magnet fails.

John B. fired this volley in
:

Nope. A magneto is self contained and requires no outside source of
power.


Where did you get that interesting piece of information?
Do they have batteries in them that finally just wear out, and you throw
the whole thing away when they do? I guess that will get (even more)
expensive on all those old Lycoming and Continental engines out there
with their magneto batteries about to run down...

Or... Just keeping in mind the old "conservation of energy" crap they
stuck us with in school (and never gave us a good alternative to), did
you maybe mean that magnetos DO require "power" to create a spark, but
that they require no outside source of ELECTRICAL power?

Byda... how do you get the computer to control precisely (and rapidly)
where the cam on the ignition rotor shaft is, in order to change the
timing on magnetos?

LLoyd

On Sat, 13 Oct 2012 18:20:29 +0700, John B.
wrote:

On Fri, 12 Oct 2012 21:42:13 -0400, wrote:

On Fri, 12 Oct 2012 12:13:21 -0500, Richard
wrote:

On 10/12/2012 12:10 PM, Richard wrote:
On 10/12/2012 7:59 AM, Existential Angst wrote:
Awl --

Would seem like a no-brainer, but goddamm, it shore has me beat!

Yeah, I know, pull the fuse!! Yeah, I know, the fuse labeled
"alternator".....

But when I did that, the alternator light or battery lite would not
come on.
AND, iirc, I DID check the voltage at the battery, to see if it went down
to 12, or was up at the ususal 13-14, and indeed, it stayed at 13-14,
indicating a working alternator.

And the engine compartment is so g-d crowded/complicated, I can hardly
tell
a wire from a hydraulic line, so it's not easy to even find the right
wire.
I figger at 100 A, the wire would have to be perty thick....

The reason for disconnecting the alternator is this:
On an old mazda 929S, the alternator went -- and I could StoG that my mpg
jumped by 15%.... would like to re-examine this phenom with my ScanGauge,
to see if it is real.

If this is indeed a true phenom, I could wangle myself a bit of a
hybrid by
just keeping a spare batt in the car, and switch in the alternator
when the
first batt dies. But basically try to do all the batt. charging at home.

Altho, there proly is no free lunch: I'll proly use my gas savings to
buy a
new battery every year?? LOL
But the actual tradeoff would be inneresting to see.

15% seems a bit high for a high MPG car, but maybe.

The alternator does take a considerable amount of power to turn.

But I'm afraid that the


Sorry - hit the wrong button.

Without the alternator your battery will not run the car for very long
at all. Solid state ignition takes power.

And you will not get much life from the battery either if you pull it
much below 50% very often.

What you want is a magneto.



Or like on an airplane - TWO magnetos. Then you still need to power
the injection - which takes more power than the ignition. And wait - a
magneto IS really just an alternator or generator - and it takes power
as well.

Nope. A magneto is self contained and requires no outside source of
power.
Did I say electrical power???? No. It takes ENGINE power to run a
Magneto The faster you run it the more power it absorbs - just like an
old generator or an alternator or Dynamo. It is basically just like a
Kettering ignition with it's own generator, all built into a nasty
little case.

On Sat, 13 Oct 2012 07:42:55 -0400, "Michael A. Terrell"
wrote:


"John B." wrote:

Nope. A magneto is self contained and requires no outside source of
power.


BS. It would have to be 'Perpetual Motion' if you were correct.
They are permanent magnet and convert motion to electricity, until the
magnet fails.

You apparently didn't read the portion of the post I was replying to,
where the guy says:
"Then you still need to power the injection - which takes more power
than the ignition. And wait - a magneto IS really just an alternator
or generator - and it takes power as well."

So no, in the context used it a magneto requires no outside source of
(electrical) power.

--
Cheers,
John B.

On Sat, 13 Oct 2012 07:40:27 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

John B. fired this volley in
:

Nope. A magneto is self contained and requires no outside source of
power.


Where did you get that interesting piece of information?
Do they have batteries in them that finally just wear out, and you throw
the whole thing away when they do? I guess that will get (even more)
expensive on all those old Lycoming and Continental engines out there
with their magneto batteries about to run down...

Or... Just keeping in mind the old "conservation of energy" crap they
stuck us with in school (and never gave us a good alternative to), did
you maybe mean that magnetos DO require "power" to create a spark, but
that they require no outside source of ELECTRICAL power?

Byda... how do you get the computer to control precisely (and rapidly)
where the cam on the ignition rotor shaft is, in order to change the
timing on magnetos?

LLoyd

You have adroitly clipped the part of the post I was responding to.

"the injection - which takes more power than the ignition. And wait -
a magneto IS really just an alternator or generator - and it takes
power as well."

Which seems to imply that the magneto requires a source of electrical
power... which I responded to, saying "No it doesn't.".

If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

--
Cheers,
John B.

"John B." wrote in message
...
...
If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

--
Cheers,
John B.

The 1970's GM HEI module:
http://www.rustpuppy.org/ignition/HEIschematic.gif

On 10/13/2012 6:20 AM, John B. wrote:

What you want is a magneto.



Or like on an airplane - TWO magnetos. Then you still need to power
the injection - which takes more power than the ignition. And wait - a
magneto IS really just an alternator or generator - and it takes power
as well.

Nope. A magneto is self contained and requires no outside source of
power.

Power - in the form or mechanical force...

On Sat, 13 Oct 2012 21:48:54 +0700, John B.
wrote:

On Sat, 13 Oct 2012 07:40:27 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

John B. fired this volley in
m:

Nope. A magneto is self contained and requires no outside source of
power.


Where did you get that interesting piece of information?
Do they have batteries in them that finally just wear out, and you throw
the whole thing away when they do? I guess that will get (even more)
expensive on all those old Lycoming and Continental engines out there
with their magneto batteries about to run down...

Or... Just keeping in mind the old "conservation of energy" crap they
stuck us with in school (and never gave us a good alternative to), did
you maybe mean that magnetos DO require "power" to create a spark, but
that they require no outside source of ELECTRICAL power?

Byda... how do you get the computer to control precisely (and rapidly)
where the cam on the ignition rotor shaft is, in order to change the
timing on magnetos?

LLoyd

You have adroitly clipped the part of the post I was responding to.

"the injection - which takes more power than the ignition. And wait -
a magneto IS really just an alternator or generator - and it takes
power as well."
The "and wait" means another thought. The injection requires more
electricity than the ignition. Dead stop.
And wait -
New thought.
A magneto IS really just an alternator or generator - and it takes
power as well.
Which seems to imply that the magneto requires a source of electrical
power... which I responded to, saying "No it doesn't.".

If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

On Sat, 13 Oct 2012 10:58:59 -0400, "Jim Wilkins"
wrote:

"John B." wrote in message
.. .
...
If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

--
Cheers,
John B.

The 1970's GM HEI module:
http://www.rustpuppy.org/ignition/HEIschematic.gif


Which has a "retard start" but does not controll timing across the RPM
band. IIRC it retards the timing 10 degrees for starting. The retard
was triggered by grounding the "R" pin - which was only on SOME of the
GM modules (called EMR if I remeber correctly). The standard 990 4
pin module did not control the timing.
There was another 4 pin variant that automatically retarded the
timing, I believe, 4 degrees on start. These were used in distributors
WITH mechanical advance. CCC didtributors with no built in advance
required full computer control.

wrote in message
...
On Sat, 13 Oct 2012 10:58:59 -0400, "Jim Wilkins"
wrote:

"John B." wrote in message
. ..
...
If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension
magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

--
Cheers,
John B.

The 1970's GM HEI module:
http://www.rustpuppy.org/ignition/HEIschematic.gif


Which has a "retard start" but does not controll timing across the
RPM
band.

No, that schematic shows how the electronically controlled low voltage
'stuff' interfaces to the high voltage.
jsw

On Sat, 13 Oct 2012 19:38:01 -0400, "Jim Wilkins"
wrote:

wrote in message
.. .
On Sat, 13 Oct 2012 10:58:59 -0400, "Jim Wilkins"
wrote:

"John B." wrote in message
...
...
If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension
magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

--
Cheers,
John B.

The 1970's GM HEI module:
http://www.rustpuppy.org/ignition/HEIschematic.gif


Which has a "retard start" but does not controll timing across the
RPM
band.

No, that schematic shows how the electronically controlled low voltage
'stuff' interfaces to the high voltage.
jsw

You replying to me or the previous poster? I didn't look at the
diagram shown (which has nothing to do with controling the spark
timing ) -it shows a simple 4 wire HEI system schematic, and it is
incomplete and inaccurate as it does not show the battery or other
primary power connections.

On Sat, 13 Oct 2012 16:32:56 -0400, wrote:

On Sat, 13 Oct 2012 21:48:54 +0700, John B.
wrote:

On Sat, 13 Oct 2012 07:40:27 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

John B. fired this volley in
:

Nope. A magneto is self contained and requires no outside source of
power.


Where did you get that interesting piece of information?
Do they have batteries in them that finally just wear out, and you throw
the whole thing away when they do? I guess that will get (even more)
expensive on all those old Lycoming and Continental engines out there
with their magneto batteries about to run down...

Or... Just keeping in mind the old "conservation of energy" crap they
stuck us with in school (and never gave us a good alternative to), did
you maybe mean that magnetos DO require "power" to create a spark, but
that they require no outside source of ELECTRICAL power?

Byda... how do you get the computer to control precisely (and rapidly)
where the cam on the ignition rotor shaft is, in order to change the
timing on magnetos?

LLoyd

You have adroitly clipped the part of the post I was responding to.

"the injection - which takes more power than the ignition. And wait -
a magneto IS really just an alternator or generator - and it takes
power as well."
The "and wait" means another thought. The injection requires more
electricity than the ignition. Dead stop.
And wait -
New thought.
A magneto IS really just an alternator or generator - and it takes
power as well.

You really seem to have a problem understanding English, don't you.

The "as well" refers to the previous subject, the need for electrical
power.

But given that you have this problem understanding, what I would call,
simple English there isn't much sense in prolonging this conversation
as I'm sure you will demonstrate further problems with comprehension
if we continue.

Which seems to imply that the magneto requires a source of electrical
power... which I responded to, saying "No it doesn't.".

If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.
--
Cheers,
John B.

On Sat, 13 Oct 2012 16:52:43 -0400, wrote:

On Sat, 13 Oct 2012 10:58:59 -0400, "Jim Wilkins"
wrote:

"John B." wrote in message
. ..
...
If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

--
Cheers,
John B.

The 1970's GM HEI module:
http://www.rustpuppy.org/ignition/HEIschematic.gif


Which has a "retard start" but does not controll timing across the RPM
band. IIRC it retards the timing 10 degrees for starting. The retard
was triggered by grounding the "R" pin - which was only on SOME of the
GM modules (called EMR if I remeber correctly). The standard 990 4
pin module did not control the timing.
There was another 4 pin variant that automatically retarded the
timing, I believe, 4 degrees on start. These were used in distributors
WITH mechanical advance. CCC didtributors with no built in advance
required full computer control.

Your illustration shows a distributor with both mechanical and vacuum
control for ignition timing :-)

But I don't see why an additional 4 degree electrical retard for
starting if the distributor already has a mechanical advance
mechanism.
--
Cheers,
John B.

"John B." wrote in message
...
On Sat, 13 Oct 2012 16:52:43 -0400, wrote:

On Sat, 13 Oct 2012 10:58:59 -0400, "Jim Wilkins"
wrote:

"John B." wrote in message
...
...
If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension
magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically
controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

--
Cheers,
John B.

The 1970's GM HEI module:
http://www.rustpuppy.org/ignition/HEIschematic.gif


Which has a "retard start" but does not controll timing across the
RPM
band. IIRC it retards the timing 10 degrees for starting. The
retard
was triggered by grounding the "R" pin - which was only on SOME of
the
GM modules (called EMR if I remeber correctly). The standard 990 4
pin module did not control the timing.
There was another 4 pin variant that automatically retarded the
timing, I believe, 4 degrees on start. These were used in
distributors
WITH mechanical advance. CCC didtributors with no built in advance
required full computer control.

Your illustration shows a distributor with both mechanical and
vacuum
control for ignition timing :-)

But I don't see why an additional 4 degree electrical retard for
starting if the distributor already has a mechanical advance
mechanism.
--
Cheers,
John B.

You would need to compare the actual advance curves that the
centrifugal and vacuum mechanisms produce with the optimal measured
values. I don't have them and couldn't release them if I did, since I
signed an NDA when I worked as a test engineer for GM engine and brake
controls.
jsw

On Sun, 14 Oct 2012 15:21:38 +0700, John B.
wrote:

On Sat, 13 Oct 2012 16:32:56 -0400, wrote:

On Sat, 13 Oct 2012 21:48:54 +0700, John B.
wrote:

On Sat, 13 Oct 2012 07:40:27 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

John B. fired this volley in
m:

Nope. A magneto is self contained and requires no outside source of
power.


Where did you get that interesting piece of information?
Do they have batteries in them that finally just wear out, and you throw
the whole thing away when they do? I guess that will get (even more)
expensive on all those old Lycoming and Continental engines out there
with their magneto batteries about to run down...

Or... Just keeping in mind the old "conservation of energy" crap they
stuck us with in school (and never gave us a good alternative to), did
you maybe mean that magnetos DO require "power" to create a spark, but
that they require no outside source of ELECTRICAL power?

Byda... how do you get the computer to control precisely (and rapidly)
where the cam on the ignition rotor shaft is, in order to change the
timing on magnetos?

LLoyd

You have adroitly clipped the part of the post I was responding to.

"the injection - which takes more power than the ignition. And wait -
a magneto IS really just an alternator or generator - and it takes
power as well."
The "and wait" means another thought. The injection requires more
electricity than the ignition. Dead stop.
And wait -
New thought.
A magneto IS really just an alternator or generator - and it takes
power as well.

You really seem to have a problem understanding English, don't you.

The "as well" refers to the previous subject, the need for electrical
power.

But given that you have this problem understanding, what I would call,
simple English there isn't much sense in prolonging this conversation
as I'm sure you will demonstrate further problems with comprehension
if we continue.

Which seems to imply that the magneto requires a source of electrical
power... which I responded to, saying "No it doesn't.".

If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.
John - I have no problem understanding what I wrote. It was ME who
wrote it. anf I DO understand how magnetos work, having worked on them
on old farm machinery 50 years ago, and on current aircraft engines as
recently as last summer. I also understand how much (electrical)
power electronic ignition and electronic fuel injection take to run,
and how much physical power it takes to produce that electricity in an
automotive environment, having been a licenced mechanic since 1971.

On Sun, 14 Oct 2012 15:30:19 +0700, John B.
wrote:

On Sat, 13 Oct 2012 16:52:43 -0400, wrote:

On Sat, 13 Oct 2012 10:58:59 -0400, "Jim Wilkins"
wrote:

"John B." wrote in message
...
...
If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

--
Cheers,
John B.

The 1970's GM HEI module:
http://www.rustpuppy.org/ignition/HEIschematic.gif


Which has a "retard start" but does not controll timing across the RPM
band. IIRC it retards the timing 10 degrees for starting. The retard
was triggered by grounding the "R" pin - which was only on SOME of the
GM modules (called EMR if I remeber correctly). The standard 990 4
pin module did not control the timing.
There was another 4 pin variant that automatically retarded the
timing, I believe, 4 degrees on start. These were used in distributors
WITH mechanical advance. CCC didtributors with no built in advance
required full computer control.

Your illustration shows a distributor with both mechanical and vacuum
control for ignition timing :-)

But I don't see why an additional 4 degree electrical retard for
starting if the distributor already has a mechanical advance
mechanism.
Not my diagram. and the actual purpose of the 10 degree retard was
for emission control reasons (on the 5 terminal units) - but it makes
starting a high compression engine easier and allows an otherwise
unmodified distributor to provide more total advance for performance
and fuel economy - while not breaking the nose off the starter or
striping the drive gear when starting.
I cannot remember the application of the 4 degree automatic advance
module or the purpose of the 4 degree advance. I DO know that they
were often replaced with the non-advance units without any serious
effects.

On Sun, 14 Oct 2012 08:33:43 -0400, "Jim Wilkins"
wrote:

"John B." wrote in message
.. .
On Sat, 13 Oct 2012 16:52:43 -0400, wrote:

On Sat, 13 Oct 2012 10:58:59 -0400, "Jim Wilkins"
wrote:

"John B." wrote in message
m...
...
If you wanted to precisely control the ignition timing using a
computer it would probably be simpler to use a "low tension
magneto"
where the magneto is a relatively low voltage generator and a
secondary coil steps the voltage up to that necessary to fire the
plugs. the low voltage stuff can then be electronically
controlled
although I have only seen this done on a gas fueled, lean burn,
stationary engine.

--
Cheers,
John B.

The 1970's GM HEI module:
http://www.rustpuppy.org/ignition/HEIschematic.gif


Which has a "retard start" but does not controll timing across the
RPM
band. IIRC it retards the timing 10 degrees for starting. The
retard
was triggered by grounding the "R" pin - which was only on SOME of
the
GM modules (called EMR if I remeber correctly). The standard 990 4
pin module did not control the timing.
There was another 4 pin variant that automatically retarded the
timing, I believe, 4 degrees on start. These were used in
distributors
WITH mechanical advance. CCC didtributors with no built in advance
required full computer control.

Your illustration shows a distributor with both mechanical and
vacuum
control for ignition timing :-)

But I don't see why an additional 4 degree electrical retard for
starting if the distributor already has a mechanical advance
mechanism.
--
Cheers,
John B.

You would need to compare the actual advance curves that the
centrifugal and vacuum mechanisms produce with the optimal measured
values. I don't have them and couldn't release them if I did, since I
signed an NDA when I worked as a test engineer for GM engine and brake
controls.
jsw

Yes of course. I was only commenting as various other engines have
gotten along with mechanical and vacuum advances over the years.

--
Cheers,
John B.

"John B." wrote in message
...
On Sun, 14 Oct 2012 08:33:43 -0400, "Jim Wilkins"
wrote:

You would need to compare the actual advance curves that the
centrifugal and vacuum mechanisms produce with the optimal measured
values. I don't have them and couldn't release them if I did, since
I
signed an NDA when I worked as a test engineer for GM engine and
brake
controls.
jsw

Yes of course. I was only commenting as various other engines have
gotten along with mechanical and vacuum advances over the years.
Cheers,
John B.

Yes, they were 'good enough' for cars, but not optimum. The controls
for late 1940's large aero engines are better examples of what could
be done mechanically to maximize performance and economy, though they
didn't have to consider the lower end of the power band or emissions.
http://www.enginehistory.org/Wright/...ompounds.shtml
"Cruise fuel consumption could be as low as 0.40 lb/hp/hr."
This is 243 g/kW-h,
http://en.wikipedia.org/wiki/Brake_s...el_consumption
not much worse than a TDI Diesel:
http://forums.tdiclub.com/showthread.php?t=208125

I recently removed the catalytic converter on my 12 year old car.
There was NO soot in the pipe ahead of it.
jsw

On Mon, 15 Oct 2012 06:04:20 -0400, "Jim Wilkins"
wrote:

"John B." wrote in message
.. .
On Sun, 14 Oct 2012 08:33:43 -0400, "Jim Wilkins"
wrote:

You would need to compare the actual advance curves that the
centrifugal and vacuum mechanisms produce with the optimal measured
values. I don't have them and couldn't release them if I did, since
I
signed an NDA when I worked as a test engineer for GM engine and
brake
controls.
jsw

Yes of course. I was only commenting as various other engines have
gotten along with mechanical and vacuum advances over the years.
Cheers,
John B.

Yes, they were 'good enough' for cars, but not optimum. The controls
for late 1940's large aero engines are better examples of what could
be done mechanically to maximize performance and economy, though they
didn't have to consider the lower end of the power band or emissions.
http://www.enginehistory.org/Wright/...ompounds.shtml
"Cruise fuel consumption could be as low as 0.40 lb/hp/hr."
This is 243 g/kW-h,

I never worked on the 3350-compound engine but I did work on the 3350
fuel injected engine and I did talk with guys that worked on the
compound engines. From what I could see, the engine came too late in
the period that reciprocating engines were used and the maintenance
costs of the compound engine were not only higher then the injected
engine but higher then for the R-4360 engine.

http://en.wikipedia.org/wiki/Brake_s...el_consumption
not much worse than a TDI Diesel:
http://forums.tdiclub.com/showthread.php?t=208125

I recently removed the catalytic converter on my 12 year old car.
There was NO soot in the pipe ahead of it.
jsw
--
Cheers,
John B.