Tooth jump = bump?

[Mhannink]

Awesome. I guess you're there everyday, but I'd have a hard time leaving for a few weeks. That type of in-depth knowledge of what's going on inside an engine. Wow. That's all I can say. The electronic part of technology has come a long way, I'd agree. I'm dissapointed in the mechanical aspect, though. These trucks are really not getting much better mileage than they were 15 years ago. Albiet, there is much more power readily available to the throttle. Where's the compromise?



I know TenneCo and Cummins worked together to develop their emission system, and granted, it's the best on the market right now, but what's in the future? I'm disgusted at the possibilities. Urea injection? Seriously? How can you be making less emissions if you're burning more fuel? Now, I know they consider the emissions they are making more environmentally friendly, and they're more stable elements, readily dispersed, but what about the effeciency? Am I off in saying the standards the Feds have put up for the industry to be met are realistically out of reach? And I'm not trying to draw you into a political discussion, only mechanical reality..... Our advancements into fuel injection have only gone so far in the last 15 years.



It does sound like a tedious, but rewarding job. The number readouts would get old, but working with the engines and experimentation of parameters sounds like sooooo much fun.

i agree 100%, this is exactly what i want to do and where im looking to go, so im drooling reading this, im also very very jealous. id love to have a real time data logger like that on my rig while im driving, then i could really tune it.



before i go any farther with my comments i have to say that for the moment im going to keep working on my project and post as much of the info for those who need a more visual form to understand it. i do hope you will weigh in and correct or expand any information i provide, this is starting to get more and more in over my head, so im going to stay closer to what i do know and keep it in mind as i move forward in my education.



anyways i am do want to ask about the emissions stuff, if you do not feel comfortable in answering the questions for any reason please do not respond. my questions though are purely mechanical just like huntitall.



so are these new engines really producing less emissions than the older ones? are they different? how are they different? how are they less? could you compare and contrast the new vs old emissions? my reason for asking is it does not make sense to me. 10 almost 15 years ago cylinder temps where lowered to produce less nox, this resulted in higher hydrocarbon out put. so to combat that they add the dpf filters, this traps the hydrocarbons to be burned off. the dpf burns them off during regen at temps above the nox threshold of 2000 degrees f. all of this as far as i can tell results in more fuel burned directly increasing emissions, lower fuel mileage, higher operating costs, lower reliability, etc. it just seems circular to me with no gain, lower temp combustion = more hydrocarbons, less nox = dpf = regen = more fuel = high temp combustion = more nox, less hydrocarbons. i dont see the gain. is it really there? do you have any information, research on just improving fuel efficency and the related emissions.



again if this is information you cant or feel uncomfortable about the can of worms it could open just plead the fifth, i will respect that and wont be offended.

 

[cerberusiam]

These trucks are really not getting much better mileage than they were 15 years ago. Albiet, there is much more power readily available to the throttle. Where's the compromise?



Our advancements into fuel injection have only gone so far in the last 15 years.

They don't get much worse mileage, thats the compromise. What gets constantly ignored is the newer trucks are heavier, bigger, and much more powerful, yet, the mileage penalty is not that much. The fact that I can cruise 70-75 in my 05 with a 1-2 mpg penalty over my 91. 5 EVEN with all the emissions additions tells me advancements are there.



Efficiency is directly effected by how weight we are trying to shove through the air how fast. Turn an old jerk pump engine up to the levels of a CR and weight them about the same and there is so little difference in mpg thats it is not worth mentioning. The big difference is the CR is doing a whole cleaner when it comes to air quality.



The actual applied injection technology has not kept up with the available technology for a couple reasons, cost and viability. The newest diesel technology is using 7-9 events and composite materials to generate some great numbers across the board, power, efficiency, and emissions. The problem is the parts are prototypes and not fully into production because, well, its so new the materials and construction capabilities are not available yet. Piezo injectors are the next generation technology that has to be proven to function correctly in an acceptable life cycle. The R&D dollars around this technology to develop and produce are HUGE and no company can afford to miss the boat or they are bankrupt.



Yes, our emissionslaws are unrelaistic. Written and develop by engineers without an ounce of grounding it the ralities of operation. It looks good on paper to them so therefore it WILL work. The reality fails to meet expectations.



The fickle buying public AND so called consumer protection laws are also a big hurdle for new technology and new ideas. If the consumer won't buy it because of perception, done. The Edsel and H2 Hummer are prime examples.



In addtion, the legal system wants to make the manufacturere liable for every nut and bolt, it ain't happening fast. Society wants EVERYTHING like they get from MacDonalds, fast and my way, so we have a group of fat fickle people that don't have a clue but drive the whole economy. Guess what will sell the best. :-laf

 

[HHhuntitall]

They don't get much worse mileage, thats the compromise. What gets constantly ignored is the newer trucks are heavier, bigger, and much more powerful, yet, the mileage penalty is not that much. The fact that I can cruise 70-75 in my 05 with a 1-2 mpg penalty over my 91. 5 EVEN with all the emissions additions tells me advancements are there.



Efficiency is directly effected by how weight we are trying to shove through the air how fast. Turn an old jerk pump engine up to the levels of a CR and weight them about the same and there is so little difference in mpg thats it is not worth mentioning. The big difference is the CR is doing a whole cleaner when it comes to air quality.

Not to by argumentative, but from my experience, the CR is not a better deal. I did count into affect the power levels. Yes, the trucks make more power, but my new trucks are not any heavier than my older trucks. My '93 weighs in close to what my '97 does, and more than my '03. While the '93 has never gotten spactacular mileage, I had an '89 CC and a '91 350 that both did, and both weighed more than my 4 door '03, which doesn't get bad mileage, itself. My point was that the mileage has not gone up, only power, and much to the sacrifice of reliability. And when you figure that the 6. 7 has lost mileage, that relates to me a poor percentage increase in technology. And I'm not saying there have been no advancements, just that I think they have been marginal compared to the growth in our trucks comfort levels and pricing.

The actual applied injection technology has not kept up with the available technology for a couple reasons, cost and viability. The newest diesel technology is using 7-9 events and composite materials to generate some great numbers across the board, power, efficiency, and emissions. The problem is the parts are prototypes and not fully into production because, well, its so new the materials and construction capabilities are not available yet. Piezo injectors are the next generation technology that has to be proven to function correctly in an acceptable life cycle. The R&D dollars around this technology to develop and produce are HUGE and no company can afford to miss the boat or they are bankrupt.



Yes, our emissionslaws are unrelaistic. Written and develop by engineers without an ounce of grounding it the ralities of operation. It looks good on paper to them so therefore it WILL work. The reality fails to meet expectations.



The fickle buying public AND so called consumer protection laws are also a big hurdle for new technology and new ideas. If the consumer won't buy it because of perception, done. The Edsel and H2 Hummer are prime examples.



In addtion, the legal system wants to make the manufacturere liable for every nut and bolt, it ain't happening fast. Society wants EVERYTHING like they get from MacDonalds, fast and my way, so we have a group of fat fickle people that don't have a clue but drive the whole economy. Guess what will sell the best. :-laf

... . and I guess that gets to the root of the problem, doesn't it. :sigh: The public. There are so many with good financing, they can afford to just go out and buy a new one, and corporate America makes sure they can, just so they can build new ones to sell. I guess I shouldn't complain. It makes more used trucks more affordable to me... ... . but from this end, I can see the windfall of the emissions laws. Right now, the 5. 9L trucks are maintaining their value, despite added mileage. At least in this area. I get calls everyday from people looking for a "good" used truck, and they are all adament about wanting the 5. 9 engine. I'm just curious where we go from here..... and how to keep these trucks running longer and more effeciently.

 

[ENafziger]

There's lots to say here, and alot I can't say here. What I can say, is that there is a 3-fold triangle in automotive performance, namely power, emissions, and economy. You can have any two of those you want at the sacrifice of the third.

Emissions regulations are driven largely by politics; however, national labs help give a sense of what is do-able to regulate and not... in other words, they provide the knowledge base to direct congressional action toward things that can actually be accomplished if the funding is there. In turn, funds are levied toward automakers by the government to allow them to perform the R&D necessary to meet the target. There's alot I could say, but I'm not going to for several reasons.

Fuel economy in our trucks hasn't increased in accordance with technology... but a first gen came with what, 160 hp? and the new 4th gens are knocking on 400 hp? And not only that, but the tailpipe emissions are nearly an order of magnitude better. Thus, they picked emissions and power at the expense of economy. The american consumer is woefully biased toward "needing" power... this creates a terribly unefficient vehicle. If you notice, it's possible to take an 80,000 lb vehicle with 350 hp and horrible aerodynamics and get 7 mpg. If things were proportioned similarly toward commuter vehicles, economy would be VASTLY improved... but public receptiveness of a vehicle that does 0 - 60 in 45 seconds would be horrible.

So, the technology has allowed a 1993 Dodge cummins (with a weight of 5400 lbs and 160 hp off the show room floor) to develop into a 2012 Dodge cummins (with a weight of 7,800 lbs and 400 hp and emissions that are at minimum 4x cleaner) with little fuel penalty.

When subscribing to emissions standards, there are Federal Drive cycles that must be run... there are different ones, but generally may include cold start emissions, stop/go, some full throttle, quick acceleration, in town driving simulation and highway. Sure, there is a fuel penalty associated with dosing nozzles, active regeneration, etc, but even so, the emissions are many times better. I'm not even sure there is enough CO coming out of a Tier 2 bin 3 car to even do any damage to you if you sat in a closed garage with the vehicle running for a week.

With some of the new combustion strategies such as RCCI, it's possible to have simultaneous NOx and PM emissions of practically zero (meaning <5 ppm Nox, and < 0. 05 FSN).

 

[HHhuntitall]

Perhaps I'm overly optimistic of our American capabilities. While I'm glad to have the power, I like the effeciency as well. And I don't want to step on any toes, I just think our technology has been held back. Partly, I'm sure, that's due to marketing abilities and the enormous cost of R&D. And I understand you have to meet a degree of balance between power and effeciency. Perhaps I'm just greedy... . but then, I look at the emission standards, and I see, what appears to me, as wasted energy, going into reducing the emissions through a heat generation process. And I don't have a better idea, or a better fuel, so I understand business has to go with what they have... ... . I just feel there should be people smarter than me who can design something better. I don't feel like I'm all that bright, but it doesn't make sense to me to use more to make less. Cummins engines are a marvel of design in themselves, so I know the company isn't lacking in intelligent engineers.



But now, I'm getting political, which I guess is where a lot of our problems lie. To get back on topic, let me ask you a question: Were you doing your testing when it was required to go to ULSD? How much of a difference did that make in your testing? In larger engines? Oil contamination? A quick synopsis, if you would, please.....

 

[cerberusiam]

So, the technology has allowed a 1993 Dodge cummins (with a weight of 5400 lbs and 160 hp off the show room floor) to develop into a 2012 Dodge cummins (with a weight of 7,800 lbs and 400 hp and emissions that are at minimum 4x cleaner) with little fuel penalty.

That is pretty much the bottom line, both politically and evironmentally correct at this juncture.



We are a power mad, style driven society demanding that from our products at any cost. The EPA and NTSB exist only as a balance to keep us from mass destruction brought on by our ever demanding needs. :-laf

 

[ENafziger]

but then, I look at the emission standards, and I see, what appears to me, as wasted energy, going into reducing the emissions through a heat generation process.

I do understand what you're saying, but it doesn't really make sense. Sure a DPF has to be regenerated, but it can be passive or active. When coupled with a heavily loaded DOC and low space velocity sized catalyst, and close-coupled to the manifold output, it's not hard to achieve passive regeneration... and you're fuel penalty is zero, nada, nothing, zippo. However, there are the people who buy a $60k diesel truck that only live 6 miles from work, never or seldom tow anything, drive conservatively, etc... . and thus, there is not a long enough period of elevated exhaust temperature to achieve passive regeneration. It is for these people primarily that active regeneration HAS to be part of the total emissions strategy... because we are Americans, and no one is going to tell us how we can or can't drive our vehicles, and who is allowed to drive what vehicle back and forth to the grocery store. But even in worst case scenerios, the fuel penalty is only ~2%... so instead of being able to drive 102 miles back and forth to the store, I can only travel 100 miles on that same amount of fuel. Doesn't seem like a big price to pay to have emissions that are more than 4x less. Worst case... 2% fuel penalty... 400% emissions benefit.

There is only so much you can do with an internal combustion engine. Sure, at work we have achieved 45% thermal efficiency. However, most people are unwilling to pay the cost of a vehicle with the technology that enables that kind of efficiency... so we drive vehicles that get 33 - 38% efficiency. There are alot of bright ideas out there, and many of them really work with solid benefit. Lump everything together, and efficiency is not bad... but cost is!

There is no way of getting around the fact that there are inefficiencies in air flow, pumping losses, mechanical parts moving, friction, chemical processes, heat loss, exothermic reactions, etc, etc. You can work to minimize the losses, and that is/has been done. But, bottom line, the physical world is was it is... . and people want what they want... and the government will do what they do... and so it's a comprimise between these three, and thus we've got what we have.

--Eric

 

[Mhannink]

thank you eric for the information, i know its probably a subject that you have lots on but cannot share, obviously there is some information i am missing about the emissions, at some point ill have to start looking more into what is going on. though i still think there is a better way, just not sure what that is.



however back to mechanics, i think we have dipped into politics plenty for one thread, things are slowing down a bit for me and so i have more time to work on what im calling blueprinting, im thinking i can have a lot of good information on sunday later afternoon, for you guys on the east coast itll probably be past your bed time and so you will see it monday, but i hope to have a lot posted, and we can start a really in depth disscussion, about performance and tuning.



hhhuntitall and eric, i do have pics and diagrams of a bosch ve pump, it should be a lot easier to explain how things are working with timing, and we should be able to see better how timing is going to affect things.

 

[Mhannink]

I do understand what you're saying, but it doesn't really make sense. Sure a DPF has to be regenerated, but it can be passive or active. When coupled with a heavily loaded DOC and low space velocity sized catalyst, and close-coupled to the manifold output, it's not hard to achieve passive regeneration... and you're fuel penalty is zero, nada, nothing, zippo. However, there are the people who buy a $60k diesel truck that only live 6 miles from work, never or seldom tow anything, drive conservatively, etc... . and thus, there is not a long enough period of elevated exhaust temperature to achieve passive regeneration. It is for these people primarily that active regeneration HAS to be part of the total emissions strategy... because we are Americans, and no one is going to tell us how we can or can't drive our vehicles, and who is allowed to drive what vehicle back and forth to the grocery store. But even in worst case scenerios, the fuel penalty is only ~2%... so instead of being able to drive 102 miles back and forth to the store, I can only travel 100 miles on that same amount of fuel. Doesn't seem like a big price to pay to have emissions that are more than 4x less. Worst case... 2% fuel penalty... 400% emissions benefit.



There is only so much you can do with an internal combustion engine. Sure, at work we have achieved 45% thermal efficiency. However, most people are unwilling to pay the cost of a vehicle with the technology that enables that kind of efficiency... so we drive vehicles that get 33 - 38% efficiency. There are alot of bright ideas out there, and many of them really work with solid benefit. Lump everything together, and efficiency is not bad... but cost is!



There is no way of getting around the fact that there are inefficiencies in air flow, pumping losses, mechanical parts moving, friction, chemical processes, heat loss, exothermic reactions, etc, etc. You can work to minimize the losses, and that is/has been done. But, bottom line, the physical world is was it is... . and people want what they want... and the government will do what they do... and so it's a comprimise between these three, and thus we've got what we have.

--Eric

that is really what engineering is all about.

 

[Mhannink]

So I got called away over the weekend a few "emergencies" came up and kept me from getting everything done so I holding to get to this weekend

 

[Mhannink]

well i am having a hell of a time getting anything accomplished on this project, so i thought maybe we could just start a disscussion going in depth into any aspect of the engine, i will pull and post any material i can find that is applicable to the different areas. so, where would we like to start, hhhuntitall you seem to be hungriest for the information, where would you like to begin.

 

[JHumphries]

Is the pressure of the fuel system variable? i. e. is it possible to get the pump to fuel at a slightly higher pressure to flow more fuel over the same amount of time after the injector opens?
Also, what is the absolute maximum power (fuel) the pump can make (flow)?

 

[Mhannink]

Is the pressure of the fuel system variable? i. e. is it possible to get the pump to fuel at a slightly higher pressure to flow more fuel over the same amount of time after the injector opens?

Also, what is the absolute maximum power (fuel) the pump can make (flow)?

your asking about the vane pump that is building the case pressure?



here is a diagram of the internals of the pump, there is a pressure regulating valve on the vane pump, however i do not see an adjustment.



increasing the pump pressure will advance timing, increase injected fuel volume, and lengthen duration. the differences would be minor i think if noticeable at all. i would speculate that to have any affect the pressure would have to be set really high, this could cause all kinds of problems, not to mention the timing would have to be adjusted to compensate.



there are really only two things that you can adjust on this pump, that is the duration, and the timing (static and dynamic).



as for the maximum flow, i do not know, that is something a fuel shop would have, as for the hp it can support, other power junkies with first gens might have a better idea than i, i think it is around 450 to 500 horse though.

 

[Mhannink]

Bosch diesel injection pump rebuild



found some great info here, looking at the internals this way, i see some room for mods that might help fuel flow.

 

[cerberusiam]

Yes, the case pressure varies with rpm. The case pressure curve is designed to meet the fueling needs for all the applications to about 2600 rpms. Beyond that the lack of adjustment and orfice sizes in the head supply circuit limit the amount of fuel available.