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| Major Debacle... |
 Posted: Thu Aug 06, 2009 7:57 pm |
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Guest
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Brent wrote:
[quote:484e7a009b]On 2009-08-06, Major Debacle <major_debacle at (no spam) REMOVEyahoo.com> wrote:
Rich is relative. More correct to say that O2 sensors are damaged by too
high a percentage of unburned HCs in the exhaust stream. Cats are
actually designed to burn off HCs before expelling the resultant
exhaust. That is what an air pump is designed to do. It injects a stream
of air into the cat expressly for the purpose of combining the O2 in the
air with HCs in order to burn them off.
Air pump? If there's a modern car on the market that needs an air pump
to meet emissions I suggest not buying it.
It's not 1975 any longer. Air pumps and other kludges are gone and
the root problem of real time fuel mixture adjustments was
addressed. Modern systems hold the fuel mixture near perfect.
[/quote:484e7a009b]
Point being made was that burning HCs in the cat don't necessarily lead
to cat failure. |
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| Alan Baker... |
| Posted: Fri Aug 07, 2009 9:05 am |
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In article <h5g255$jo9$1 at (no spam) news.eternal-september.org>,
Major Debacle <major_debacle at (no spam) REMOVEyahoo.com> wrote:
[quote:2fc556c43e]Brent wrote:
On 2009-08-06, Major Debacle <major_debacle at (no spam) REMOVEyahoo.com> wrote:
Rich is relative. More correct to say that O2 sensors are damaged by too
high a percentage of unburned HCs in the exhaust stream. Cats are
actually designed to burn off HCs before expelling the resultant
exhaust. That is what an air pump is designed to do. It injects a stream
of air into the cat expressly for the purpose of combining the O2 in the
air with HCs in order to burn them off.
Air pump? If there's a modern car on the market that needs an air pump
to meet emissions I suggest not buying it.
It's not 1975 any longer. Air pumps and other kludges are gone and
the root problem of real time fuel mixture adjustments was
addressed. Modern systems hold the fuel mixture near perfect.
Point being made was that burning HCs in the cat don't necessarily lead
to cat failure.
[/quote:2fc556c43e]
It would if it were more than just a whisper of unburnt HCs.
--
Alan Baker
Vancouver, British Columbia
<http://gallery.me.com/alangbaker/100008/DSCF0162/web.jpg> |
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| Brent... |
| Posted: Fri Aug 07, 2009 8:55 pm |
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On 2009-08-08, SilentOtto <silentotto at (no spam) hotmail.com> wrote:
[quote:b206bd0c9d]But, I did some quick looking around on the web and there were -
plenty- of references to problems associated with running modern
engines too lean in various help forums.
So, it would seem to me that since running too lean is still a
problem, then there must still be a certain percentage of the fuel
that's deliberately reaming unburned under normal operating
conditions.
[/quote:b206bd0c9d]
For crying out loud... Those forums are people who MODIFY their cars.
They turn their cars into rolling engineering experiments. They add
superchargers and turbo chargers (which add air). They play with the
fuel map. They change injectors. Sometimes they get it wrong and cause
damage. That's the nature of such things.
If you a buy a car and don't start messing with it, the only way there
will be a problem with running lean is if a part FAILS. Parts such as an
O2 sensor or a TPS. |
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| Scotius... |
| Posted: Fri Aug 07, 2009 11:43 pm |
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On Thu, 06 Aug 2009 12:59:34 -0500, russotto at (no spam) grace.speakeasy.net
(Matthew Russotto) wrote:
[quote:7792c2789d]In article <8lnk75pqd615irkbcm2thb7tcp490pdfid at (no spam) 4ax.com>,
Scotius <yodasbud at (no spam) mnsi.net> wrote:
Yes, the super carburetor IS a myth. Late carburetors, and even more
so, modern FI systems, adequately prepare the fuel/air mixture. Only a
fraction of one percent of fuel is left unburned in normal operating
conditions.
If that's true then why are those engines rated at only
20-some percent efficient?
Because the efficiency of an internal combusion engine is not equal to
the fraction of the fuel it burns. The limit on efficiency of an
internal combustion engine is simply one minus the ratio of the
temperature of the combustion gas over the temperature of the outside
air. Both temperatures in absolute degrees, of course.
I read some years back that there were people working on
producing a ceramic engine. Actually, it could already be done then,
but was cost prohibitive, so I guess I should say they were looking at
bringing down the cost of production of ceramic engines.
Since the ceramics can withstand temperatures far higher than
steel, the engines could operate hotter and more efficiently.
Sure, presuming you could get the mixture to burn that much hotter and
you could efficiently remove the heat before the next cycle starts.
The first part is pretty easy. The second, not so much.
The supercarburetor is NOT a myth, however. I've read enough
about it to have formed a reasonable opinion, in my opinion, and mine
is that it's not.
Electronic fuel injection provides a near ideal fuel to air ratio, and
yet fails to achieve the purported benefits of the supercarburetor. Therefore,
no such device existed.
[/quote:7792c2789d]
It wasn't an improvement of thermal efficiency that made the
super-carburetor what it was. It was that it got more out of the gas
by acting as a catalyst to a degree, from what I've read. It was a
while ago that I read it and I don't recall the site, but if I find it
I will let you know. |
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| hls... |
| Posted: Sat Aug 08, 2009 5:54 am |
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"Scotius" <yodasbud at (no spam) mnsi.net> wrote in message
[quote:2ab8876879]It wasn't an improvement of thermal efficiency that made the
super-carburetor what it was. It was that it got more out of the gas
by acting as a catalyst to a degree, from what I've read. It was a
while ago that I read it and I don't recall the site, but if I find it
I will let you know.
[/quote:2ab8876879]
In such context, a super carburetor is a myth, pure and simple. |
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| Scotius... |
| Posted: Sat Aug 08, 2009 9:30 am |
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On Sat, 8 Aug 2009 06:54:53 -0500, "hls" <hls at (no spam) nospam.nix> wrote:
[quote:e5ceb645fd]
"Scotius" <yodasbud at (no spam) mnsi.net> wrote in message
It wasn't an improvement of thermal efficiency that made the
super-carburetor what it was. It was that it got more out of the gas
by acting as a catalyst to a degree, from what I've read. It was a
while ago that I read it and I don't recall the site, but if I find it
I will let you know.
In such context, a super carburetor is a myth, pure and simple.
[/quote:e5ceb645fd]
If you want to suggest that it's a "myth" because no one has
yet PROVEN it to be real, that's okay. After all, you can't go around
insisting the Earth is flat unless you can "prove", it.
I will say this until I find some references though: I have
read some convincing material on the net about this. |
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| Matthew Russotto... |
| Posted: Sat Aug 08, 2009 10:00 am |
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In article <g14q7559pelgp2p4qfp8sg5bajsrbrf1jr at (no spam) 4ax.com>,
Scotius <yodasbud at (no spam) mnsi.net> wrote:
[quote:e4fc0da485]On Thu, 06 Aug 2009 12:59:34 -0500, russotto at (no spam) grace.speakeasy.net
(Matthew Russotto) wrote:
Electronic fuel injection provides a near ideal fuel to air ratio, and
yet fails to achieve the purported benefits of the supercarburetor. Therefore,
no such device existed.
It wasn't an improvement of thermal efficiency that made the
super-carburetor what it was. It was that it got more out of the gas
by acting as a catalyst to a degree, from what I've read. It was a
while ago that I read it and I don't recall the site, but if I find it
I will let you know.
[/quote:e4fc0da485]
A catalyst for what? A fuel air mixture doesn't _need_ a catalyst to
go "boom". You're repeating snake-oil claims.
--
It's times like these which make me glad my bank is Dial-a-Mattress |
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| Matthew Russotto... |
| Posted: Sat Aug 08, 2009 10:09 am |
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Guest
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In article <2ec66b11-c78c-4857-a533-616f82eabc3e at (no spam) n2g2000vba.googlegroups.com>,
SilentOtto <silentotto at (no spam) hotmail.com> wrote:
[quote:323d1af652]
But, I did some quick looking around on the web and there were -
plenty- of references to problems associated with running modern
engines too lean in various help forums.
[/quote:323d1af652]
Modern engines run too lean when there's some problem with the fuel
delivery system. Sometimes it's due to an ECU programming problem
but usually it's some sort of mechanical failure.
[quote:323d1af652]So, it would seem to me that since running too lean is still a
problem, then there must still be a certain percentage of the fuel
that's deliberately reaming unburned under normal operating
conditions.
[/quote:323d1af652]
No. Running too lean, in a modern engine, refers to when there's too
little fuel and thus some oxygen in the mixture remains unconsumed.
It's simply the opposite of running rich.
--
It's times like these which make me glad my bank is Dial-a-Mattress |
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| hls... |
| Posted: Sat Aug 08, 2009 10:23 am |
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Guest
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"Scotius" <yodasbud at (no spam) mnsi.net> wrote in message
news:ee6r75da41ggas0s14k4ordtmkvj6bno6j at (no spam) 4ax.com...
[quote:11ac16aeac]On Sat, 8 Aug 2009 06:54:53 -0500, "hls" <hls at (no spam) nospam.nix> wrote:
In such context, a super carburetor is a myth, pure and simple.
If you want to suggest that it's a "myth" because no one has
yet PROVEN it to be real, that's okay. After all, you can't go around
insisting the Earth is flat unless you can "prove", it.
I will say this until I find some references though: I have
read some convincing material on the net about this.
[/quote:11ac16aeac]
When you can prove it, then the flat earth and the super carburetor will
be entered into science. Until then, the earth is not flat, unless it is
in
the form of a map, and there is no super carburetor. |
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| Scotius... |
| Posted: Sat Aug 08, 2009 3:42 pm |
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Guest
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On Sat, 8 Aug 2009 11:23:35 -0500, "hls" <hls at (no spam) nospam.nix> wrote:
[quote:599fe66735]
"Scotius" <yodasbud at (no spam) mnsi.net> wrote in message
news:ee6r75da41ggas0s14k4ordtmkvj6bno6j at (no spam) 4ax.com...
On Sat, 8 Aug 2009 06:54:53 -0500, "hls" <hls at (no spam) nospam.nix> wrote:
In such context, a super carburetor is a myth, pure and simple.
If you want to suggest that it's a "myth" because no one has
yet PROVEN it to be real, that's okay. After all, you can't go around
insisting the Earth is flat unless you can "prove", it.
I will say this until I find some references though: I have
read some convincing material on the net about this.
When you can prove it, then the flat earth and the super carburetor will
be entered into science. Until then, the earth is not flat, unless it is
in
the form of a map, and there is no super carburetor.
[/quote:599fe66735]
I can accept that. I'll still post any links I find about it
to this group though in case anyone who understands the mechanics
wants to take a look. Deal? |
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| brian whatcott... |
| Posted: Sat Aug 08, 2009 6:16 pm |
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Matthew Russotto wrote:
[quote:c0469e4bfd]... why are those engines rated at only
20-some percent efficient?
Because the efficiency of an internal combustion engine is not equal to
the fraction of the fuel it burns. The limit on efficiency of an
internal combustion engine is simply one minus the ratio of the
temperature of the combustion gas over the temperature of the outside
air. Both temperatures in absolute degrees, of course.
[/quote:c0469e4bfd]
Close - its the temperature of the COMPRESSED mixture not the temp of
the burning gas
Brian W |
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| hls... |
| Posted: Sat Aug 08, 2009 9:19 pm |
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"Scotius" <yodasbud at (no spam) mnsi.net> wrote in message
[quote:6478236176]
I can accept that. I'll still post any links I find about it
to this group though in case anyone who understands the mechanics
wants to take a look. Deal?
[/quote:6478236176]
Post whatever you like.. Many of us have a very good grasp of
physics, chemistry, and mechanics. We will welcome your right to
post, but will challenge you when you are over the edge (of the flat
earth). ;>) |
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| hls... |
| Posted: Sat Aug 08, 2009 9:20 pm |
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"brian whatcott" <betwys1 at (no spam) sbcglobal.net> wrote in message
[quote:6cc3d74475]Close - its the temperature of the COMPRESSED mixture not the temp of
the burning gas
Brian W
[/quote:6cc3d74475]
I dont believe that is quite right either, Brian. |
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| Matthew Russotto... |
| Posted: Sun Aug 09, 2009 4:37 pm |
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Guest
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In article <gcKdndzPJ5gViOPXnZ2dnUVZ_qudnZ2d at (no spam) giganews.com>,
brian whatcott <betwys1 at (no spam) sbcglobal.net> wrote:
[quote:848a3adbce]Matthew Russotto wrote:
... why are those engines rated at only
20-some percent efficient?
Because the efficiency of an internal combustion engine is not equal to
the fraction of the fuel it burns. The limit on efficiency of an
internal combustion engine is simply one minus the ratio of the
temperature of the combustion gas over the temperature of the outside
air. Both temperatures in absolute degrees, of course.
Close - its the temperature of the COMPRESSED mixture not the temp of
the burning gas
[/quote:848a3adbce]
No, the temperature of the compressed mixture is meaningless. In the
ideal case, the temperature of the compressed mixture is equal to the
sink temperature; in a real engine, that's not the case of course, and
is a source of inefficiency.
--
It's times like these which make me glad my bank is Dial-a-Mattress |
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| Alan Baker... |
| Posted: Sun Aug 09, 2009 11:27 pm |
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Guest
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In article <g14q7559pelgp2p4qfp8sg5bajsrbrf1jr at (no spam) 4ax.com>,
Scotius <yodasbud at (no spam) mnsi.net> wrote:
[quote:ad613205f5]On Thu, 06 Aug 2009 12:59:34 -0500, russotto at (no spam) grace.speakeasy.net
(Matthew Russotto) wrote:
In article <8lnk75pqd615irkbcm2thb7tcp490pdfid at (no spam) 4ax.com>,
Scotius <yodasbud at (no spam) mnsi.net> wrote:
Yes, the super carburetor IS a myth. Late carburetors, and even more
so, modern FI systems, adequately prepare the fuel/air mixture. Only a
fraction of one percent of fuel is left unburned in normal operating
conditions.
If that's true then why are those engines rated at only
20-some percent efficient?
Because the efficiency of an internal combusion engine is not equal to
the fraction of the fuel it burns. The limit on efficiency of an
internal combustion engine is simply one minus the ratio of the
temperature of the combustion gas over the temperature of the outside
air. Both temperatures in absolute degrees, of course.
I read some years back that there were people working on
producing a ceramic engine. Actually, it could already be done then,
but was cost prohibitive, so I guess I should say they were looking at
bringing down the cost of production of ceramic engines.
Since the ceramics can withstand temperatures far higher than
steel, the engines could operate hotter and more efficiently.
Sure, presuming you could get the mixture to burn that much hotter and
you could efficiently remove the heat before the next cycle starts.
The first part is pretty easy. The second, not so much.
The supercarburetor is NOT a myth, however. I've read enough
about it to have formed a reasonable opinion, in my opinion, and mine
is that it's not.
Electronic fuel injection provides a near ideal fuel to air ratio, and
yet fails to achieve the purported benefits of the supercarburetor.
Therefore,
no such device existed.
It wasn't an improvement of thermal efficiency that made the
super-carburetor what it was. It was that it got more out of the gas
by acting as a catalyst to a degree, from what I've read. It was a
while ago that I read it and I don't recall the site, but if I find it
I will let you know.
[/quote:ad613205f5]
No. People can do the math and there is nothing "more" available to "get
out of the gas".
Sorry.
--
Alan Baker
Vancouver, British Columbia
<http://gallery.me.com/alangbaker/100008/DSCF0162/web.jpg> |
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