I have straight piped 6.7 turbo back
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From: El Dorado, Ks
I have straight piped 6.7 turbo back
I have been reading alot about you guys wanting to know what happens when you do the straight pipe mod to the 6.7? Well I dont know what it has done to the few other guys that have tried this but I am getting a code. My edge Juice W/ Attitude moniter is telling me that it is a P244A which is (Diesel Particulate pressure to low). I just flash the computer with the Edge and it goes away and about every 20 miles in town it will come back on but out on the highway it does NOT ever set the code. It does not seem to lose any powerwhen the light comes on, Although it did gain quite a noticeable amount of snap and my fuel milage is now a consistent 17.5 to 18 mpg. (with only 4000 miles) The truck is still very quiet and it will blow a little smoke not a lot but definitely noticable.
1 ton Dually 4 wheel drive mega cab
Friday my partner and I are going to put dual 6" stacks on her will let you know more when the time comes
Does it hurt the truck or take any power away to take the silencer ring out of 6.7
1 ton Dually 4 wheel drive mega cab
Friday my partner and I are going to put dual 6" stacks on her will let you know more when the time comes
Does it hurt the truck or take any power away to take the silencer ring out of 6.7
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John,
Didn't read and understand what you said before dude LOL... To big a hurry around here trying to get both ends to meet everyday and all the things I have said I would make meet
I do think hurry is the mother to most problems, that and trying to skimp on the money LOL...
The valve your talking about is right under the EGR basically, I thought of this as the air control valve or more along the lines of throttle valve.
Glad to hear I ain't the only one messing around with this. As I said, I would have never messed with this as I don't have the time too. But hey its not really working out that well if you ask me and the motor is awsome if you ask me. So I thought what the heck I will try and make a fumble into a gain here LOL... For lack of a better more diplomatic way of typing this
The bungs are an easy thing dude, first go to a good known auto store and have them pick you up a couple of the O2 sensor bungs from the muffler suppliers as they fit all the O2 sensors and they weld these all the time to headers and such.
Then get you 2 lug nuts that are the 14mmX1.50 size those will fit the differentail fitting just wonderful where the flare nuts and tubing are in the exhaust by the driveshaft. Lug nuts are easy and cheap and have good metal to them once you get past the coatings.
The other two sensors area little smaller and finer thread, a 12mmX1.25 lug nut fits these if memory serves me correct. Just make sure not to drill a very large hole for either of the last four sensors mentioned here. You will want to cut the lug nuts down on both sizes so that the flared tubing ends as well as the thermo-coupling will bottom out on the tubing or pipe you weld these nuts too...
This will help them seal off the exhaust gases and get the sensor unit snug to the pipe. I only had to shave off about a 1/4" of both sizes for this and a chop saw worked good holding the nut with visegrips in the vise on the saw...
Least that is what I rounded up for a fit that has been working and was cheap and easy... Here are a few quick PIC's. Didn't get time to pull down anything yet as a friend came by with a four bolt main block that he wanted me to weld up a couple of cracks in the water jackets. So I ran out of time again...
The first one above has a view of the rear O2 sensor and the spooled or flanged out oxidizer rifling vein. The next view is of the inside of the differential sensor taps and the lines and where they were bolted to the oxidizer I just put a small machine nut and bolt to stiffen them up together, workes ok for now till I am sure of what I will end up with an make a better method to mount these...
The next is a view from the down pipe looking back and how I hung this at the same points as the OEM system.
The last one is a close up view of the first flange bolted to the down pipe flange, this sytem is easy to put on and take off. That way once you are through off roading and lets say you need to go get an inspection sticker since the tree limb you mis-judged and busted out the windshield, its not like any biggy deal if you know what I mean LOL
Didn't read and understand what you said before dude LOL... To big a hurry around here trying to get both ends to meet everyday and all the things I have said I would make meet
I do think hurry is the mother to most problems, that and trying to skimp on the money LOL...The valve your talking about is right under the EGR basically, I thought of this as the air control valve or more along the lines of throttle valve.
Glad to hear I ain't the only one messing around with this. As I said, I would have never messed with this as I don't have the time too. But hey its not really working out that well if you ask me and the motor is awsome if you ask me. So I thought what the heck I will try and make a fumble into a gain here LOL... For lack of a better more diplomatic way of typing this
The bungs are an easy thing dude, first go to a good known auto store and have them pick you up a couple of the O2 sensor bungs from the muffler suppliers as they fit all the O2 sensors and they weld these all the time to headers and such.
Then get you 2 lug nuts that are the 14mmX1.50 size those will fit the differentail fitting just wonderful where the flare nuts and tubing are in the exhaust by the driveshaft. Lug nuts are easy and cheap and have good metal to them once you get past the coatings.
The other two sensors area little smaller and finer thread, a 12mmX1.25 lug nut fits these if memory serves me correct. Just make sure not to drill a very large hole for either of the last four sensors mentioned here. You will want to cut the lug nuts down on both sizes so that the flared tubing ends as well as the thermo-coupling will bottom out on the tubing or pipe you weld these nuts too...
This will help them seal off the exhaust gases and get the sensor unit snug to the pipe. I only had to shave off about a 1/4" of both sizes for this and a chop saw worked good holding the nut with visegrips in the vise on the saw...
Least that is what I rounded up for a fit that has been working and was cheap and easy... Here are a few quick PIC's. Didn't get time to pull down anything yet as a friend came by with a four bolt main block that he wanted me to weld up a couple of cracks in the water jackets. So I ran out of time again...
The first one above has a view of the rear O2 sensor and the spooled or flanged out oxidizer rifling vein. The next view is of the inside of the differential sensor taps and the lines and where they were bolted to the oxidizer I just put a small machine nut and bolt to stiffen them up together, workes ok for now till I am sure of what I will end up with an make a better method to mount these...
The next is a view from the down pipe looking back and how I hung this at the same points as the OEM system.
The last one is a close up view of the first flange bolted to the down pipe flange, this sytem is easy to put on and take off. That way once you are through off roading and lets say you need to go get an inspection sticker since the tree limb you mis-judged and busted out the windshield, its not like any biggy deal if you know what I mean LOL
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I just read this thread and I can tell you right now that your going to get the code till you throw some new software on the ECM if anyone ever gets some hacked out, or your going to need to do something as I have to fake the system to think it has some restriction to the exhaust system. Just would be best to have something that doesn't collect particulate for our off-road system...
You can do this a number of ways but if your not really lucky building up any kind of other restriction it will build up soot and carbon on the sensors and all on the inside of the combustion chambers and on out the system.
One other thing of note here I have seen with well over 20 years of welding in gas plants on piping systems there is two basic flows of gas and/or solid liquids. One is as our cat. and DPF filters are which is more or less a straightening vein. Its that by design if nothing else in how the small filter media allows the gas to flow straight through... This type of flow action is great for seperating fluids and or gases. This is not what we need to try and do here JIMO as I would think we need to keep the particulate matter suspended in the gases the best we can and allow it to be carried out the tailpipe with the discharge. Otherwise we will seperate things and have it all fall-out inside the system and collect.
Which is all great and fine if we was leaving as is and going to try and trap all this and do the regen every so often and burn it off... For highway use its just fine sense they have nothing better, at least for now. Again IMHO its not working out just exactly right just yet anyway as they are going to need to knock heads together and may need to hire some outside help to fix all the issues with this plan of attack on the diesel motors. Maybe some people that have actually gotten dirty once or twice and had to pay for things like this all the time while it was not working and in the shop LOL...
Anyway, back to the other type of flow, one that I am using and for more reasons than just one is the rifling or twisting if you follow me. The rifling vein as I am using does allow me to load up the system pressure-wise somewhat anyway, at different places as needed, and it also helps a great deal by stirring things and keeping the particulate matter all suspended, allowing it to flow right out with the exhaust discharge.
Now the other really cool thing here using the rifling vein is, unlike the straightening vein, once the exhaust gas is put into a spin and gets it going through the exhaust pipe it tends to follow through in this motion and is way less likely to get to tumbling and bouncing around which will slow things down in a state of flow as it sort of hunts as it heads out...
This rifling vein system would be great with a Aero-Muffler if one wanted to install that in the system as well. They would work excellent together. You need to realise there is right and left rifling veins and one would be wise to use all the same for the system for a smooth flow out the tail LOL...
Sorry this gets hard for me to type on here and keep to a two sentence answer...Hope this might help.
You can do this a number of ways but if your not really lucky building up any kind of other restriction it will build up soot and carbon on the sensors and all on the inside of the combustion chambers and on out the system.
One other thing of note here I have seen with well over 20 years of welding in gas plants on piping systems there is two basic flows of gas and/or solid liquids. One is as our cat. and DPF filters are which is more or less a straightening vein. Its that by design if nothing else in how the small filter media allows the gas to flow straight through... This type of flow action is great for seperating fluids and or gases. This is not what we need to try and do here JIMO as I would think we need to keep the particulate matter suspended in the gases the best we can and allow it to be carried out the tailpipe with the discharge. Otherwise we will seperate things and have it all fall-out inside the system and collect.
Which is all great and fine if we was leaving as is and going to try and trap all this and do the regen every so often and burn it off... For highway use its just fine sense they have nothing better, at least for now. Again IMHO its not working out just exactly right just yet anyway as they are going to need to knock heads together and may need to hire some outside help to fix all the issues with this plan of attack on the diesel motors. Maybe some people that have actually gotten dirty once or twice and had to pay for things like this all the time while it was not working and in the shop LOL...
Anyway, back to the other type of flow, one that I am using and for more reasons than just one is the rifling or twisting if you follow me. The rifling vein as I am using does allow me to load up the system pressure-wise somewhat anyway, at different places as needed, and it also helps a great deal by stirring things and keeping the particulate matter all suspended, allowing it to flow right out with the exhaust discharge.
Now the other really cool thing here using the rifling vein is, unlike the straightening vein, once the exhaust gas is put into a spin and gets it going through the exhaust pipe it tends to follow through in this motion and is way less likely to get to tumbling and bouncing around which will slow things down in a state of flow as it sort of hunts as it heads out...
This rifling vein system would be great with a Aero-Muffler if one wanted to install that in the system as well. They would work excellent together. You need to realise there is right and left rifling veins and one would be wise to use all the same for the system for a smooth flow out the tail LOL...
Sorry this gets hard for me to type on here and keep to a two sentence answer...Hope this might help.
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Jeb_H:
I was looking to do exactly what you did, but i was thinking of putting the Cat off of a 2004.5 Cummins 600 engine.. weldign this into the pipe inbetween the two pressure senors that go on each side of the DPF normally would create a pressure difference.. probable enuff to make the engine stop throwing codes... Only thing is if it clogs up.. So i figured punch some holes thru it.. but only a couple so that there is still a pressure difference. Problem is these Cats are ceramic.. So maybe something else would work better.. ?
I was looking to do exactly what you did, but i was thinking of putting the Cat off of a 2004.5 Cummins 600 engine.. weldign this into the pipe inbetween the two pressure senors that go on each side of the DPF normally would create a pressure difference.. probable enuff to make the engine stop throwing codes... Only thing is if it clogs up.. So i figured punch some holes thru it.. but only a couple so that there is still a pressure difference. Problem is these Cats are ceramic.. So maybe something else would work better.. ?
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From: San Luis Obispo, CA
Just a thought.
If I recall correctly there are 2 pressure taps that are connected to 1 sensor that determines the pressure differential. I see no benefit to simulating this pressure differential in the exhaust system. By simulating the differential you are trying to add the same pressure drop a clean DPF provides. That introduces a restriction which will rob power. A solution would be to place a venturi in front of one of the pressure taps so it sees lower pressure than the other. The problem with that is it will allow soot to collect and kill the sensor.
What if the 2 taps were connected to another source of pressure. Make a small tube with one pressure tap at the front, some sort of restriction to cause the same pressure drop as the DPF and the second tap at the rear. Attach the rear to the exhaust system so it draws in air when the engine is running. Clean cool air so the sensors never soot up and no restrictions in the exhaust pipe.
Or if that can't work remove it from the exhaust and use a small electric fan pressurizing the tube etc..
If I recall correctly there are 2 pressure taps that are connected to 1 sensor that determines the pressure differential. I see no benefit to simulating this pressure differential in the exhaust system. By simulating the differential you are trying to add the same pressure drop a clean DPF provides. That introduces a restriction which will rob power. A solution would be to place a venturi in front of one of the pressure taps so it sees lower pressure than the other. The problem with that is it will allow soot to collect and kill the sensor.
What if the 2 taps were connected to another source of pressure. Make a small tube with one pressure tap at the front, some sort of restriction to cause the same pressure drop as the DPF and the second tap at the rear. Attach the rear to the exhaust system so it draws in air when the engine is running. Clean cool air so the sensors never soot up and no restrictions in the exhaust pipe.
Or if that can't work remove it from the exhaust and use a small electric fan pressurizing the tube etc..
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Joined: Feb 2002
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From: Red Deer, Alberta Canada
If the rear sensor point protruded into the pipe slightly with the opening facing downstream, it will create a slight negative pressure on the sensor port. This may be enough to fool the system.
What someone has to do is actually measure the pressure drop across a clean DPF so it can be simulated.
What someone has to do is actually measure the pressure drop across a clean DPF so it can be simulated.
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From: Llano, TX
I'm no electrical engineer, but it seems to me it would be easier to fool the sensors electronically rather than mechanically. Maybe it would be possible to put a resistor or something similiar in line with one of the sensors, thus simulating a pressure difference using electricity? As I said, I know little about electricity, but it seems like that would be easier than trying to change exhaust flow. Just brainstorming.
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From: DFW, TX
I'm no electrical engineer, but it seems to me it would be easier to fool the sensors electronically rather than mechanically. Maybe it would be possible to put a resistor or something similiar in line with one of the sensors, thus simulating a pressure difference using electricity? As I said, I know little about electricity, but it seems like that would be easier than trying to change exhaust flow. Just brainstorming.
To me it would be more practical fooling it on the electronic side, instead of building a mcgyver contraption to fool it mechanically...
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ok, i talked to some mechanics today.. We decided that you just need to find out what voltage the two sensors are runnin at when you have a clean DPF and the truck is on the highway. Then connect resistors that will simulate that signal in ohms. You would need to do it to 3 sensors. The 2 pressure sensors and the Exhaust temp sensor. By doing this you can completely take off the sensors ( not even tap the straight pipe for them) and have a restriction less straight pipe exhaust. You just have to have a starscan to find out the voltage that the pressure sensors and exhaust temp sensor are runnin at, so that you can do the math and figure out the ohms for the resistors for the 3 sensors.
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Joined: Jan 2007
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From: Indiana
I think the biggest problem will be what they call a "rationality code". The ECM will see...... lets say 6000 miles...... and the pressure differential between the two sensor never changes, the truck never needs a regeneration and thus - turn on the check engine light. If you don't mind resetting the light every now and again, maybe it will work, but I think it is a short term solution to a long term problem.
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From: alberta canada
Jeb_H:
I was looking to do exactly what you did, but i was thinking of putting the Cat off of a 2004.5 Cummins 600 engine.. weldign this into the pipe inbetween the two pressure senors that go on each side of the DPF normally would create a pressure difference.. probable enuff to make the engine stop throwing codes... Only thing is if it clogs up.. So i figured punch some holes thru it.. but only a couple so that there is still a pressure difference. Problem is these Cats are ceramic.. So maybe something else would work better.. ?
I was looking to do exactly what you did, but i was thinking of putting the Cat off of a 2004.5 Cummins 600 engine.. weldign this into the pipe inbetween the two pressure senors that go on each side of the DPF normally would create a pressure difference.. probable enuff to make the engine stop throwing codes... Only thing is if it clogs up.. So i figured punch some holes thru it.. but only a couple so that there is still a pressure difference. Problem is these Cats are ceramic.. So maybe something else would work better.. ?
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From: El Dorado, Ks
My truck has the sensors tapped back into it and I am getting the P244A low pressure code but like I said maybe we could get a performance muffler and put between the sensors to make back pressure it would not create as much as a cat but maybe enough?
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From: El Dorado, Ks
anyway will it hurt the truck to have this P244A low pressure code going off. will it hurt the truck or not, not having any back pressure. the truck does run alot better and the mileage is as well. I would not like to put the stock pipe back on but if it is going to make it break I need to let me know if you know anything.
Thanks guys
Thanks guys