put rattle back in the cummins

[CRicker]

My truck is an 03, and I love the truck, couldn't ask for a better truck and the truck sounds great with the mods that I have done. The only problem is the new trucks doesn't have the same sound or rattle as previous year's dodge trucks. I know there are alot of you guys out there that love the quietness of the 3rd gens, and i respect your opinions, but please dont insult me or ask me why I want my truck to sound better because I know an overwhelming amount of people who agree with me, that if there is a way of overriding the pilot injection and/or what ever else there is that is making these trucks sound different we would buy the product or do whatever you can do to change this. Any ideas greatly appreciated, I know there has got to be a way, just waiting for someone to come up with it.

 

[jwduke]

Thats the problem, thats what everyone (almost) wants, a "quieter" diesel.



Thats the first thing out of everyones mouth, when I tell them I drive a Dodge with a turbo Cummins diesel, "How noisy is it?"

 

[p-Bar]

Just loosen up the rod bolts a 1/4 turn

 

[Grizzly]

My truck is an 03, and I love the truck, couldn't ask for a better truck and the truck sounds great with the mods that I have done. The only problem is the new trucks doesn't have the same sound or rattle as previous year's dodge trucks. I know there are alot of you guys out there that love the quietness of the 3rd gens, and i respect your opinions, but please dont insult me or ask me why I want my truck to sound better because I know an overwhelming amount of people who agree with me, that if there is a way of overriding the pilot injection and/or what ever else there is that is making these trucks sound different we would buy the product or do whatever you can do to change this. Any ideas greatly appreciated, I know there has got to be a way, just waiting for someone to come up with it.

I agree, I liked the rattle on my '95, but my wife like the quietness of the '05. Well at least we don't have to yell at each other anymore nor turn up the volume up on the radio.

 

[CRicker]

I know it, but it would be great to get rid of the pilot injection for those of us that want the traditional cummins sound back, maybe then we can have the best of both worlds!

 

[rbattelle]

In the beginning of the 3rd gen forums there was a lot of anticipation that there would be boxes to allow you to turn off pilot injection. It dawned on me the other day why there hasn't been a single one to date: to turn off pilot injection would require a completely modified fuel map.



The CM845 (CM850 for you 04. 5-up owners, I think) engine controller is programmed with a fuel map which accounts for the presence of multiple injection events. Since each injection consumes some of the (finite) available oxygen in the cylinder, it can only be a fraction of the total volume of fuel required to produce the advertised power and torque. This leaves enough available oxygen for the next shot of fuel. In other words, the total volume of fuel injected (pilot volume + main volume) is calibrated to produce rated power.



If you wanted to turn off pilot injection, then, you'd have to shift the entire fuel map to provide the same total volume of fuel as before, but in a single shot rather than 2 (or more). Doing so would require a new ECM; to do it with an aftermarket box would probably be prohibitively expensive, since it would have to be pretty sophisticated in order to determine the total desired fuel volume before the first pulse for pilot injection comes through. There are probably other complications that I'm not aware of.



I think that's why we haven't seen a "pilot injection eliminator". EPA may also have something to do with it.



-Ryan

 

[klenger]

A lot of the 2nd gen noise came from the injection pump, not the engine. HPCR got rid of that (&*^(&) thing.

 

[daveshoe]

I noticed that distinctive Cummins sound in a parking lot just today. Imagine my surprise when I saw a third genner making all that sound. Probably a straight pipe ,but a nice rattle all the same.

 

[TowPro]

I have an 02 and its louder then my 98 was. I think that was because the 98 had under the hood insulation. today when were were looking at the 06 I started it to show my wife how quiet it was. My 12 year old daughter was sitting in the back seat and I noticed I could hear her talking! I love the sound of a diesel but 8 hour trips towing the camper and having to keep saying "what did you say" as they try to talk to me is getting old!



I loaded the Diesel. wav from here into my cell phone as a ring tone, if I need to hear the 2nd generation sound I can have my wife call me. In fact I told her when the 06 comes in she will have to call me every morning when I get into the garage so I can hear the engine start

 

[Tony T.]

I have always liked the Cummins diesel rattle myself, but do like the quietness also especially going through drive-thru's (banks,fast food,etc). Would be nice if it was just a simple flip of the switch for the best of both worlds rattle,quiet,rattle,quiet . Seems though if I'm not mistaken was there a issue with Fords PS 6. 0 and them just turning off the pilot injection on some of the earlier 6. 0 for some sort of problem they had. I can't remember all the details though.



Tony

 

[Boondocker]

My truck's engine is as loud as any diesel pickup I've heard. I think the ISB ETH motors are the loudest. I'm talking engine clatter here, not exhaust.



At best, I don't mind it. But having to yell at someone standing at your driver's side open window is annoying if not embarrassing. I love the sound of my truck, but not the volume. I've done quite a bit of noise reduction to tone it down without altering the character.



Buying this truck new was pretty much my first experience with diesels. I'll never forget the first time I heard it. It was a cold overcast day, on a small car lot, surrounded by concrete buildings. The salesman went to get it, about 50 feet away. When he fired it up, I was shocked as the sound reverberted through me, and my right shoulder hurt. I think my wife punched me as she yelled - "Is that our truck!?" :-{} "Is that how loud it is!!!?" The salesman gave us the time-honored, it's always louder when it's cold



Now that I'm a diesel enthusiast and a little more experienced, I've come to favor the sound of the 12-valve CTD. I don't know what it is, it just sounds right, maybe not as harsh as the 24-valve.



Neil

P. S. Why does my computer sound exactly like my truck when Windows starts? Oh yeah, diesel. wav

 

[CRicker]

In the beginning of the 3rd gen forums there was a lot of anticipation that there would be boxes to allow you to turn off pilot injection. It dawned on me the other day why there hasn't been a single one to date: to turn off pilot injection would require a completely modified fuel map.



The CM845 (CM850 for you 04. 5-up owners, I think) engine controller is programmed with a fuel map which accounts for the presence of multiple injection events. Since each injection consumes some of the (finite) available oxygen in the cylinder, it can only be a fraction of the total volume of fuel required to produce the advertised power and torque. This leaves enough available oxygen for the next shot of fuel. In other words, the total volume of fuel injected (pilot volume + main volume) is calibrated to produce rated power.



If you wanted to turn off pilot injection, then, you'd have to shift the entire fuel map to provide the same total volume of fuel as before, but in a single shot rather than 2 (or more). Doing so would require a new ECM; to do it with an aftermarket box would probably be prohibitively expensive, since it would have to be pretty sophisticated in order to determine the total desired fuel volume before the first pulse for pilot injection comes through. There are probably other complications that I'm not aware of.



I think that's why we haven't seen a "pilot injection eliminator". EPA may also have something to do with it.



-Ryan

If it comes down to swapping out ecm's, if someone can come up with a way to modify one to do that, then that would be fine! Like I said before I know plenty of 3rd gen guys out there who would do that. I'm sure someone will figure a way out its just a matter of time. I've waited almost 3 years, I can wait a little longer.

 

[J.Davy]

Would there be a power gain if there was no pilot injection?

 

[rbattelle]

Would there be a power gain if there was no pilot injection?

I doubt it, but don't know for sure. Pilot injection's primary purpose in life is to reduce delay angle and rate of pressure rise, and help the main fuel charge combust more completely. A reduction in delay angle and rate of pressure rise means less detonation. It also means you get a significantly quieter engine. By helping the main charge combust more completely (since the cylinder is extra-hot when the main charge arrives), you improve tailpipe emissions. I'm not sure exactly what effect it has on mean effective pressure, but peak pressure (which is typically used to size the engine components) should be unaffected.



If there were no pilot injection, then, you'd have a "traditional" shape of the crank-angle diagram, by which I mean the delay period would be much longer and the rate of pressure rise would be much higher. This would result immediately in increased noise, and I *assume* increased emissions as the single charge of fuel won't burn quite as completely.



There will likely be some people out there who will vehemently disagree with that entire argument.



-Ryan

 

[AGrubbs]

Rattle...

I would think that taking the delay out between pilot and main injection event would be somewhat equivelent to advanceing the timeing of the fuel injection.

While it would not ACTUALLY advance the pilot pulse, you WOULD have the main injection starting earlyer and finishing earlyer than 'normal' if you use the same amount of fuel and fuel pressure.



This would help somewhat ( I think ) with economy and EGT. So putting more fuel in earlyer should let you burn MORE fuel earlyer in the stroke, which should gain more power per equal amount of fuel than if you injected the same amount later on. (due to retarded EPA timeing)

This would give you the option of running more fuel and ending at the same time in the stroke as the 'quiet' injection setup.



I think if someone could just find the area in the ECU code that determines the number of deg. between pilot shutoff, and start of main injection, and just bypass where it loads the delay value, you could still use the stock fuel maps and be happy with the result.



The only thing that would maybe be a problem is if you ever wanted to run a power box, then it might be looking for the 2 (or more) injection events in its software and would not function correctly on your truck. So probably if you

are happy with the noise but no added power, then something like this idea would work. Othewise if you run a power box then this probably would not be a good idea.



Although if you were going to get into the code and remove the delay, then you could probably go in and fiddle with the fuel maps too, and you would not need a power box! Something like a MAD Marco's ECM tweek would be what you end up with.

I wonder if he's working on the '03 ECU for more power. . ? Anyone Know?



Oh well, with the price of fuel, maybe I better leave my truck as is. . :{



Drive ON!

 

[Scrappy]

I did the tone ring mod that advances injection timing on my truck a couple weeks ago and it rattles a little more AND is getting better fuel economy.

 

[Sled Dog]

I would think that taking the delay out between pilot and main injection event would be somewhat equivelent to advanceing the timeing of the fuel injection.

While it would not ACTUALLY advance the pilot pulse, you WOULD have the main injection starting earlyer and finishing earlyer than 'normal' if you use the same amount of fuel and fuel pressure.



This would help somewhat ( I think ) with economy and EGT. So putting more fuel in earlyer should let you burn MORE fuel earlyer in the stroke, which should gain more power per equal amount of fuel than if you injected the same amount later on. (due to retarded EPA timeing)

This would give you the option of running more fuel and ending at the same time in the stroke as the 'quiet' injection setup.



I think if someone could just find the area in the ECU code that determines the number of deg. between pilot shutoff, and start of main injection, and just bypass where it loads the delay value, you could still use the stock fuel maps and be happy with the result.



The only thing that would maybe be a problem is if you ever wanted to run a power box, then it might be looking for the 2 (or more) injection events in its software and would not function correctly on your truck. So probably if you

are happy with the noise but no added power, then something like this idea would work. Othewise if you run a power box then this probably would not be a good idea.



Although if you were going to get into the code and remove the delay, then you could probably go in and fiddle with the fuel maps too, and you would not need a power box! Something like a MAD Marco's ECM tweek would be what you end up with.

I wonder if he's working on the '03 ECU for more power. . ? Anyone Know?



Oh well, with the price of fuel, maybe I better leave my truck as is. . :{



Drive ON!

I'm waiting to see if that Marco fella can find a 3rd gen up grade. Oo.

 

[WCounts]

I'm shure that the ecm on the third gens can be programed. If the dealer can make changes so can others with the right equipment.

I would like to have only one injection event and the fuel controlled by my foot without wanting to see boost. I believe this would make the truck more drivable.

When ever someone can do this I'll be first in line for one. Soon I hope.

 

[CRicker]

I'm shure that the ecm on the third gens can be programed. If the dealer can make changes so can others with the right equipment.

I would like to have only one injection event and the fuel controlled by my foot without wanting to see boost. I believe this would make the truck more drivable.

When ever someone can do this I'll be first in line for one. Soon I hope.

I agree 100% with you! I would definitly be second in line

 

[AGrubbs]

One other thing...

Just was thinking while sitting here reading... and came up with something else to be said for rattles...



If you get rid of 1/2 of the openings and closeings of the injector by going to one injection event instead of 2 (or more), wouldn't you double the life of your injectors??



By having them doing half the number of valve shifts per power stroke the injector should last longer before wear takes it out of service. . This assumes that other things (like heat and good fuel quality) are not a factor in why your injectors go TU...







AG. .