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Discussion Starter · #1 ·
So what is it? Seems like an injection pump but it doesn't look gear driven like a VE pump or a P-pump? I tried to research but all I could come up with is folks wanting to sell modded ones...
 

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High pressure common rail. ~27,000psi+, no individual injection lines, hence the "common rail" just like gasoline fuel injection vehicles have. For the first time (for cummins ISB) injectors are not simply poppet valves that open anytime pressure is over xpsi. Now they have piezo electric connections and open like fuel injected cars. Each individual injector cost between $300-$1300 (x6)

Haven't seen inside of one yet, although I'm willing to bet it is much less complex than anything else seen on a B series ever before.
 

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s ǝoɾ said:
High pressure common rail. ~27,000psi+, no individual injection lines, hence the "common rail" just like gasoline fuel injection vehicles have. For the first time (for cummins ISB) injectors are not simply poppet valves that open anytime pressure is over xpsi. Now they have piezo electric connections and open like fuel injected cars. Each individual injector cost between $300-$1300 (x6)

Haven't seen inside of one yet, although I'm willing to bet it is much less complex than anything else seen on a B series ever before.
Dang, you beat me to it, although they do bolt up like the old mechanical styles, much easier to swap out than the old ones
 

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I always thought the Master Tech guy looked a lot like the farting preacher.
 

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talk about turning a simple engine into a complex system...  I just watched the 4 videos, sure they're logical and I could follow it, but they made my head swim too...
 

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I would say some parts of the engine are definitely simplified from older variants, while other parts obviously get complex. Piezo is pretty complex and I do not exactly understand the pinciple. "shock a rock, it grows and forces a pintle open with light speed, no residual magnetism or saturation delay" Can't quite fathom that yet, I guess.

Hard to believe this video is 8 years old and much has changed since then.

The lift pump moved to the tank somewhere around mid 04, 07.5 brought about the 6.7L with all kinds of new "goodies" such as variable geometry turbo, exhaust regen, built in exhaust brake, 6 speed automatic, injectors that went up in price ~3x from the already expensive 5.9HPCR, and much more.

The CP3 has already lasted longer than any IP placed on a dodge B series though. The VE lasted for 5 years, 4.5 years for the p7100, 4.5 years for the vp44, the CP3 has already lasted 8 years with no immediate end in sight.

2012 will likely be a revealing year...
 

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The CP-3 is like a fuel pump in your fuel injected gasoline car, only is has a lot higher fuel pressure. 

A gasoline multi-point fuel injection system IS a common rail injection system.  You have a fuel pump that pressurizes a fuel rail.  The fuel rail has electronic injectors that spray fuel when the computer says to. 


The relationship between MPI and common rail injection is like the relationship between the low voltage in your house and the high voltage in the power lines.  The wires in your house are protected by fuses and circuit breakers.  So are the wires on the poles.  Even though both systems look very different, the are actually the same.
 

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The distribution theory is the same, but the application is a little different.  High pressure feedback, the routing of dumped fuel, etc is much more involved in this engine than with a gasoline rail injector with a simple regulator. 

Of course all this stuff is required when you have diesel at 25,000+ psi, but I wonder excluding lowering the emissions are you getting any benefit from the complexity?
 

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ToxicDoc said:
The distribution theory is the same, but the application is a little different. High pressure feedback, the routing of dumped fuel, etc is much more involved in this engine than with a gasoline rail injector with a simple regulator.

Of course all this stuff is required when you have diesel at 25,000+ psi, but I wonder excluding lowering the emissions are you getting any benefit from the complexity?
The benefits are tremendous. NVH, drivability and engine life. Common rail engines can get much more power per liter, are more efficient, and start better under all conditions. They have the ability to adapt to changes in altitude, temperature, and load, instantly and more accurately without the operator even knowing that it's going on. On some common rail engines, the operator can select how much power he wants or set the max GPH his machine will burn, all on the fly.

The emissions stuff on these diesels is bull crap. Gasoline exhaust is much worse than what a diesel puts out. The only reason diesel exhaust burns the eyes is the same reason a campfire does- particulate. I believe that diesels should have emissions regulations, but what they are required now is way beyond reasonable.
 

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There is a lot more than simple carbon particulate in there. Some chemicals that I cannot even explain their presence. (toluene, formaldehyde, acetone, cyanide why ???)

Of course the billion dollar target is NOx which is kind of hard to eliminate from the inlet tract. Water injection time. ;) If it is not eliminated/reduced, you end up with Nitric Acid

So obviously regen, SCR, urea, aqueous ammonia, egr, ect ect are NOT desirable solutions, as we already know.

IF you could do something to cure all of that, how would you go about it? Time to speak up. ;)

Otherwise, soon the ol ISB will also be straddled with urea and suffer from things such as "ammonia slip".
 

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The NOx must be dealt with.  It makes all the nasty stuff and the nasty stuff even nastier.  The other things, well not so much.  Either way, gasoline vehicles put out way more hydrocarbons which are much worse than NOx. 

NOx is created in the combustion chamber.  Since diesels have high combustion chamber temps and must have them to work right, NOx will always be a problem.  Catalytic converters do a great job of breaking N and O apart.  I feel the road the automakers are going down is the best road to meet the emission standards, but are the standards too strict?  I wonder if emission controls on vehicles have reached the point of diminishing returns.

Who are the primary contributors of pollution?  It used to be vehicles and still might be, but what about power plants and factories?  Welding and metal smelting have to create huge amounts ozone, NOx, and other stuff how much do....oh wait....we sent all that kind of work to China.  Never mind.  I guess that leaves power plant emissions.

Anyone know what's in power plant exhaust?
 

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That depends on.

Some plants have such powerful scrubbers the air comes out cleaner than it went in. They are beginning to even pull basic c02 out of the stream.

Their processes are more refined as well. Fluidized bed, water-gas shift, ect ect.

Unfiltered, obviously much more nasty with sulfur, mercury, URANIUM (embedded into coal deposits) and every other heavy metal known to man.

From what I understand, my particular area, 30% of air pollution is specifically diesel related. The rest shared by industry and gasoline ect ect. I'm going to have to check on that more some other day.

I mean I'm no expert I just drive them leisurely.

Normal cats do not work well in diesels. They depend on rich-lean cycling that happens in gasoline engines. The in effect, DEPEND on HC to balance out the mix. Obviously w/o HC they do not work so well. Nothing to scavenge up the excess oxygen.
 

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s ǝoɾ said:
Normal cats do not work well in diesels. They depend on rich-lean cycling that happens in gasoline engines. The in effect, DEPEND on HC to balance out the mix. Obviously w/o HC they do not work so well. Nothing to scavenge up the excess oxygen.
I didn't even think about that. It's kind of hard to light off a converter without HC to burn.
 

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magnumRC said:
I didn't even think about that. It's kind of hard to light off a converter without HC to burn.
It's funny, the inherent tendency of gasoline engines to misfire (where HC comes from) is actually much like a dpf regen cycle, but it is using much less fuel, much more often.

A diesel engine dumps fuel maybe every 20 minutes (I am totally making that number up, I don't know how often regen happens) that is the HC required to react with the NOX. In the mean while it stores NOx in a "trap" waiting for those hydrocarbons. The part I am not sure about, but believe may be correct, is this is done through retarded injection timing? That would be the easiest way.

Gasoline engines kind of do the same thing, except they have several "regen" cycles where HC is dumped into the exhaust. We call those misfires. ;D Of course the normal rich/lean cycling even without misfire, still produces carbon monoxide which will help strip that oxyen molecule(s) off the NOx and let it escape as co2 and pure nitrogen.

It's funny, the various ammonia or urea schemes, actually inject more nitrogen into the exhaust BUT the hydrogen attached, can scavenge up the oxygen from NOx, resulting in water and nitrogen.

That stuff is all theoretical. We end up with so many of these "unexplained" emissions, because the various reactions do not occur under ideal conditions (ratios, pressures, temperatures, ect ect) along with unpredicted additions such as engine oil additives getting thrown into the mix.

Obviously in the ideal world, or on paper you only end up with pure water and pure co2 (along with extra atmospheric air). In the real world, even those 2 can mix together to form weird secondary byproducts like carbonic acid.

Soon I might be able to tell more about it hopefully...
 

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Discussion Starter · #17 ·
s ǝoɾ said:
It's funny, the inherent tendency of gasoline engines to misfire (where HC comes from) is actually much like a dpf regen cycle, but it is using much less fuel, much more often.

A diesel engine dumps fuel maybe every 20 minutes (I am totally making that number up, I don't know how often regen happens) that is the HC required to react with the NOX. In the mean while it stores NOx in a "trap" waiting for those hydrocarbons. The part I am not sure about, but believe may be correct, is this is done through retarded injection timing? That would be the easiest way.

Gasoline engines kind of do the same thing, except they have several "regen" cycles where HC is dumped into the exhaust. We call those misfires. ;D Of course the normal rich/lean cycling even without misfire, still produces carbon monoxide which will help strip that oxyen molecule(s) off the NOx and let it escape as co2 and pure nitrogen.

It's funny, the various ammonia or urea schemes, actually inject more nitrogen into the exhaust BUT the hydrogen attached, can scavenge up the oxygen from NOx, resulting in water and nitrogen.

That stuff is all theoretical. We end up with so many of these "unexplained" emissions, because the various reactions do not occur under ideal conditions (ratios, pressures, temperatures, ect ect) along with unpredicted additions such as engine oil additives getting thrown into the mix.

Obviously in the ideal world, or on paper you only end up with pure water and pure co2 (along with extra atmospheric air). In the real world, even those 2 can mix together to form weird secondary byproducts like carbonic acid.

Soon I might be able to tell more about it hopefully...
So what you're telling me is that all this emissions stuff isn't an exact science and hundreds of millions of dollars are being spent on "guesses" that may or may not lead to another problem? Great...

Also, I would totally watch those videos Joe but the computer I use doesn't have sound. Though by your and other posts I'm getting a pretty clear picture. :)
 

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Gas engines put out bunches of HC in normal operation (even without misfire) because it's impossible and undesirable to maintain a perfect mixture all the time.  If a gas engine was running stoich at wide open throttle, pieces would melt.  Gas engines also run better when the mixture is slightly rich.  There is very little O2 in gasoline exhaust too.

Running slightly rich is not an option with a diesel.  It's not possible to do reasonably.  One of the great things about a diesel is that they will burn nearly all HC at all times.  If you up the HC to the combustion chamber you up the RPM.  There is a lot of O2 in the exhaust, even during regen.  The O2 will always react first which screws up the NOx reaction.

Timing is retarded to lower the combustion chamber temps too.  Lower temps there mean less NOx is produced.  It also means lower power to the wheels, less MPG and higher EGTs.

The best solution would be (cringe) public transportation.  As public transportation exists now, it is one of the dumbest and stupidest things around.  It's a huge waste of money.

Hang on to your hats because here comes a huge rant again! {rant}

Up to the late 40s America public transportation was privately owned, very profitable, and the best in the world.

Enter General Motors. 

There are two things that tick me off.  First is when people or companies intentionally rip off me or other people.  Second is when I get lied to.

Thank you General Motors for destroying privately owned public transit in the late 40s and early 50s so you could sell more buses and cars.  You ripped off America.

Thank you General Motors for making a commercial saying you paid off the government loans, which is not a lie.  Not telling the public that you used government money to pay off the government loans is morally a lie, but legally not a lie.

:-\ I need to go back to bed.






 

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magnumRC said:
The best solution would be (cringe) public transportation. As public transportation exists now, it is one of the dumbest and stupidest things around. It's a huge waste of money.
100% correct. I have been stating this for quite some time as well. Less vehicles with slightly more pollution per vehicle, ends up better than more vehicles with slightly less pollution per vehicle, or that is my guess anyways. I would hate for any gov't funds, mandates, or regulations be involved, and much more prefer this to be left a conscious decision left to the individual.

Many metro lines have been privatized, atleast to some extent, leaving the municipalities as just the overseeing regulating body, but leaving maintenance and operations to contractors.

On the last note. HC is not really a product of rich conditions. Rich ends up with H20 and carbon monoxide. The H is very easily given up. If there is HC, the mixture did not light off regardless of the 4 types of causes (rich, lean, compression, ignition) Yes, any of the 4 will result in HC (in a gas engine anyways) including lean. Carbon monoxide=rich (the reason old emission stickers had a percentage spec for CO) HC=misfire, HC+CO=rich misfire. The text book spec mentions even a brand new engine experiencing misfire atleast 6% of the time. Even the one that idles smooth as glass is misfiring as indicated by the mode$06 PID data. Most vehicles just won't through a code unless it misfires atleast several thousand times in a row. Even one miss less than that, and no code, just PID info.

Hard_runner67 said:
So what you're telling me is that all this emissions stuff isn't an exact science and hundreds of millions of dollars are being spent on "guesses" that may or may not lead to another problem? Great...
The internal combustion engine isn't even an "exact science". We (the world) do not even know exactly how it works yet. Before anyone claims to know exactly how it works, I'll just say it. They are wrong. There are so many uncertainties, flukes, and things that cannot be predicted through computer modeling, since computer models can only be based off of info we already know.

I believe I told you about the friend who went to Cummins school, where they refuse to allow students to get 100% in the classes? Hypothetically, if you answer every question correctly and perform all procedures to exact OE standards, you will only get a 99%. Cummins reasoning?
We don't even know how these engines work. There is no way you could...
That's some deep philosophy, but ever so true.

It used to not be an exact science, that's why they called me. ;D No no, jk. I too will be taking the same WAG (wild ass guesses)

Yep, you are exactly right, they are merely guesses that may or may not fix the current problem and may equally cause more of a problem. Realistic testing is hard to achieve. Chemistry class says if I light a jar of gasoline, diesel, or propane, I will only get 2 things. Water and carbon dioxide. They say that nitrogen is stable and non reactive. It is assumed no carbon will remain as particulate or deposits. It is assumed engine oil on the walls will not burn. Calcium, zinc, and other additives will not react either. It is also assumed that both the air and the fuel are "pure".
 

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Joe- I'm cut in now.  I was on the misfire level of completely dead cylinder.  I was thinking, "What???  Misfire all the time?"

Chrysler's OBDIII spec on misfire logging was something like 50rpm difference between cylinders.  A hard misfire was something like 100 or 200 RPM.  A misfire difference of less than 50rpm is barely noticeable and 200rpm is a completely dead cylinder. 

Initially, misfire monitors showed the handful of misfires during real time but they changed it to not show them later on.  Too many mechanics were thinking that the misfires showed meant there was something wrong.

My Mom told me about how she could take an electric trolley for a few cents and go anywhere around town and the suburbs.  They came by every 5 minutes.  Then they disappeared.

What makes that even worse is that here in the Northwest nearly all of our power is hydroelectric.

I'm not big on global warming (I actually think it might be a big lie), but I am a big fan of seeing blue sky and not having my lungs burn in the city.  That's what the emission agenda should be pushing.

 
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