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Thought about going to something smaller, less restrictive and cheaper but I can tell you now that after a 20 mile drive that with some rather large holes in the exhaust pipes and a less than complete muffler I got around 28lbs of boost and the exhaust was very loud. With the new factory original system installed, the coach is quiet as a mouse with the pedal down and still getting 28lbs of boost, 

ive always been a believer that they knew what they were doing for the most part when they built these rigs, engine performance and noise abatement were obviously on their minds when the put bigger motors and huge mufflers in them, so, for me stock ISL and garbage can size muffler keeps me at the speed limit towing 10k car hauler in the middle lane and can sneak in anywhere pretty quietly 😊

Edited by moxy1962
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3 hours ago, moxy1962 said:

Thought about going to something smaller, less restrictive and cheaper but I can tell you now that after a 20 mile drive that with some rather large holes in the exhaust pipes and a less than complete muffler I got around 28lbs of boost and the exhaust was very loud. With the new factory original system installed, the coach is quiet as a mouse with the pedal down and still getting 28lbs of boost, 

 

The above comment brings up a question in my mind.  I’m not sure that boost (28pi) has anything to to with increased efficiency from a more open exhaust. I would think the turbo boost would likely be the same, but possibly there is less restriction on exhaust with an Aero type system, and maybe more benefit from whatever boost you have.  
Im not trying to get into the “which is best” debate, but is there any difference in the boost between close and open exhaust systems?

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7 minutes ago, David White said:

The above comment brings up a question in my mind.  I’m not sure that boost (28pi) has anything to to with increased efficiency from a more open exhaust. I would think the turbo boost would likely be the same, but possibly there is less restriction on exhaust with an Aero type system, and maybe more benefit from whatever boost you have.  
Im not trying to get into the “which is best” debate, but is there any difference in the boost between close and open exhaust systems?

As far as I know, boost is created by exhaust passing through the turbo, spinning impellers, the faster the exhaust the higher boost, if there are restrictions I expect that slows things down and creates less boost, my point was the with literally no restriction by virtue of my rotted out exhaust I achieved 28 lbs, once proper exhaust was installed I still made 28 lbs, so in my mind the only savings would be weight using a smaller muffler/resonator, with a likely increase in exhaust noise.

28lbs of boost is 28lbs of boost, as far as exhaust efficiency past the turbo, as far as I know it doesn’t matter after the turbo what happens as long as exhaust can exit unrestricted, which I would say judging by my results or does

 

 

Edited by moxy1962
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17 minutes ago, moxy1962 said:

Waste gates control turbo boost as far as I know 

That’s my point. I was thinking the waste gate opens and closes to allow exhaust to pass into the turbo, prior to getting into exit exhaust.  I would not think the exhaust/ muffler would have anything to do with the boost. Maybe I’m wrong.

Edited by David White
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31 minutes ago, moxy1962 said:

Waste gates control turbo boost as far as I know 

Bolt on exhaust modifications are a great way to get more horsepower out of your turbocharged vehicle. ... Turbo back exhausts accomplish this increased flow by widening the pipe size and removing restrictive factory bends. With this type of modification you will immediately notice an HP gain.

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I replaced my stock muffler with the Aero 4040XL, only because it appeared to be an inexpensive, stainless steel replacement for the original.  I expected NO change in boost and NO change in performance...and got neither.  I have yet to see a dyno before-and-after comparison, but I THINK some huge increases in HP are largely between the ears of the owner...just my personal experience.  Exhaust noise increase was minimal.

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Unless your factory system is very restrictive, any change in HP will be minimal.

I straight piped mine to save money and eliminate the muffler, which is the first thing to rust out.
The sound increase was minimal from the drivers seat, where it counts. 😎

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A lot of coach owners report better performance with straight through exhaust or straight through mufflers, and comment the performance gains are worth the extra exhaust noise, I’ve read less turns, bigger diameter, Less restrictive mufflers or resonators allow exhaust gases to exit vehicle quicker using less energy to pump them increasing turbo efficiency. . My ISL has 6 bends in the exhaust 3 of them are 90 degree bends, 3 are 45’s, travelling about 10 or 12 feet, by all accounts fairly restrictive exhaust set up, yet as I have indicated when compared to the rusted out exhaust with substantial holes in turbo down pipe, there was 0 loss in boost with complete new factory style muffler and piping which by all accounts is the measuring stick for turbo diesel performance, and it’s quiet.

 

Edited by moxy1962
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4 hours ago, moxy1962 said:

A lot of coach owners report better performance with straight through exhaust or straight through mufflers, and comment the performance gains are worth the extra exhaust noise, I’ve read less turns, bigger diameter, Less restrictive mufflers or resonators allow exhaust gases to exit vehicle quicker using less energy to pump them increasing turbo efficiency. . My ISL has 6 bends in the exhaust 3 of them are 90 degree bends, 3 are 45’s, travelling about 10 or 12 feet, by all accounts fairly restrictive exhaust set up, yet as I have indicated when compared to the rusted out exhaust with substantial holes in turbo down pipe, there was 0 loss in boost with complete new factory style muffler and piping which by all accounts is the measuring stick for turbo diesel performance, and it’s quiet.

 

Boost level doesn't have much to do with power output.  Without additional fuel, you could have 100psi of boost and still make the same power, or even less due to the pumping losses associated with making more boost pressure.
Higher boost simply provides more oxygen, which ALLOWS the engine to burn more fuel, but doesn't increase power in and of itself.
It's certainly not a very good indicator of exhaust efficiency.
Like I said, any gains from exhaust are small and unlikely to be able to be felt from the driver's seat.

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50 minutes ago, dl_racing427 said:

Boost level doesn't have much to do with power output.  Without additional fuel, you could have 100psi of boost and still make the same power, or even less due to the pumping losses associated with making more boost pressure.
Higher boost simply provides more oxygen, which ALLOWS the engine to burn more fuel, but doesn't increase power in and of itself.
It's certainly not a very good indicator of exhaust efficiency.
Like I said, any gains from exhaust are small and unlikely to be able to be felt from the driver's seat.

Boost goes up so does fuel metering, fuel alone doesn't create power hense the need for the turbo,  fuel without air or in this case forced induction doesn’t do squat but you know that, so if my boost increases so does the fuel delivered to each cylinder, conversely when the boost drops the fueL decreases, more boost, more fuel, more power, can’t change the laws of physics my friend, 

You ever notice that performance set ups for Diesel engines include intake, exhaust and turbos? if you can’t get the exhaust out  you can’t get fresh air and  fuel in, exhaust is everything 

Edited by moxy1962
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5 minutes ago, moxy1962 said:

Boost goes up so does fuel metering, fuel alone doesn't create power hense the need for the turbo,  fuel without air or in this case forced induction doesn’t do squat but you know that, so if my boost increases so does the fuel delivered to each cylinder, conversely when the boost drops the fueL decreases, more boost, more fuel, more power, can’t change the laws of physics my friend, 

 

Not necessarily.  A diesel doesn't operate with a relatively constant Air/Fuel ratio like a gasoline engine.
You can increase fuel and power without increasing boost, but that also results in high exhaust temps and excessive smoke.
Once you have enough boost to allow your injection pump to reach maximum fuel , further increases in boost pressure will actually reduce power slightly due to pumping losses.

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11 minutes ago, dl_racing427 said:

Not necessarily.  A diesel doesn't operate with a relatively constant Air/Fuel ratio like a gasoline engine.
You can increase fuel and power without increasing boost, but that also results in high exhaust temps and excessive smoke.
Once you have enough boost to allow your injection pump to reach maximum fuel , further increases in boost pressure will actually reduce power slightly due to pumping losses.

Diesels run lean by design, excessive lean condition will not make more power no, but that’s not what I said, my ISL will maintain the afr based on available boost, if my boost is lower due to a restrictive exhaust or intake the afr will stay at optimum and that would mean less fuel and air, which means less power, which some may feel or notice.

The point of my Comment is, the stock exhaust set up is sufficient to allow max boost on my engine, therefore allowing the most Efficient afr, no need to worry about restrictive factory exhaust, it is fine. Any seat of the pants feeling some may feel is likely about the sound not about the power. 

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With the Cummins ECM, increasing boost pressure DOES NOT cause additional fuel to be delivered...DOES NOT cause additional fuel to be delivered...DOES NOT cause additional fuel to be delivered.  Would be nice if that were the case, but NOT SO.  Additional boost will lower EGT under all conditions, but the max programmed fuel from the ECM is not changed.  To increase power, you must increase fuel delivery and you will have to do that with an add-on device like Agricultural Solutions or similar.

It might seem reasonable that if the ECM sees higher boost, it will supply additional fuel, but it simply DOES NOT do that.  All you get from additional boost is the ABILITY to burn more fuel efficiently, but the Cummins ECM will not supply additional fuel no matter what boost pressure you achieve.  I increased my boost pressure from 22-23 PSI to 30+ PSI.  It lowered EGT considerably, but did not increase performance.  Adding the Ag Solutions "chip" increased power by a modest amount while raising EGT.  The increased boost kept the EGT at about the pre-chip temperature.

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10 hours ago, vanwill52 said:

With the Cummins ECM, increasing boost pressure DOES NOT cause additional fuel to be delivered...DOES NOT cause additional fuel to be delivered...DOES NOT cause additional fuel to be delivered.  Would be nice if that were the case, but NOT SO.  Additional boost will lower EGT under all conditions, but the max programmed fuel from the ECM is not changed.  To increase power, you must increase fuel delivery and you will have to do that with an add-on device like Agricultural Solutions or similar.

It might seem reasonable that if the ECM sees higher boost, it will supply additional fuel, but it simply DOES NOT do that.  All you get from additional boost is the ABILITY to burn more fuel efficiently, but the Cummins ECM will not supply additional fuel no matter what boost pressure you achieve.  I increased my boost pressure from 22-23 PSI to 30+ PSI.  It lowered EGT considerably, but did not increase performance.  Adding the Ag Solutions "chip" increased power by a modest amount while raising EGT.  The increased boost kept the EGT at about the pre-chip temperature.

So you are trying to say that the engine uses the same amount of fuel at idle as it does at full throttle, that no matter what the demand, more power needs more fuel, afr and egt would say you are wrong, not sure where you are going with your assumption, but to make more power the engine burns more fuel, with turbo charged applications the demand for fuel increases dramatically to maintain an afr of between 14-1 and 16 - 1 for turbo applications, if the ecm did not add addition fuel the engine would lose power, there is a balance between egt, pollution and power , the ecm ensures clean burning powerful reasonable egt running, simple as that, the engine burns more fuel the higher the boost, your repeated comment that it doesn’t is wrong, I’ve never said once anything about exceeding engine parameters with respect to boost, fuel pressure or metering, 

Edited by moxy1962
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Van,

My Banks Power-Pack appears to have taken a dump on our trip to New Hampshire last May. We had stopped at a rest area about 150 miles from our final destination for the summer. Upon leaving the rest area I had absolutely no boost nor did I have any readings on my two Banks gauges, the EGT or the Boost. I pulled over to the side of the highway and installed the "bypass" plug that was given to me at the time of installation which bypasses the Ottomind ECM and returns the engine back to normal.

We drove the rest of the way to our jobs at Totem Pole Park with no problems. A few weeks later I checked the 5 amp power fuse to the Ottomind ECM to see if it had blown (as it had done before back in 2017 on our Western NP Trip) but it had not. I can only assume that the Ottomind ECM has now completely failed. I will do some more troubleshooting before we leave to return to Florida in October but I don't have my hopes up that I will find anything positive.

From posts that I have read on iRV2.com, others that had the Banks Power-Pack system installed have stated that their Ottomind ECM failed around the 6-8 year time-frame. I looked up when I had mine installed and it turns out that it had been working almost 8 years now as it was installed in July of 2013. Banks chose not to design their own proprietary ECM for the Power-Pack System as there wasn't enough of a market for them to recoup their research and design costs so I am SOOL.

Do you recommend the AG Diesel Solutions ECM for the Cummins ISC 8.3L with the CAPS Fuel System that you referenced in a post above?

I wish I could find something that would take the place of the failed Ottomind ECM utilizing the bigger turbo that Banks had installed and their gauges but that is only a pipe-dream.

Thanks!

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