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Coachmen Joe · 10-24-2018, 05:25 AM

Did a search first and didn't come up with anything. Anyway I purchased a 2002 Coachmen Cross Country with a 260HP engine. This thing is anemic and that is being kind. I had problems with simply not enough power going thru the mountains north of Phoenix. I have been told that one can simply go to their Cummings dealer/shop and have the engine file changed. I would like to go 330HP or 350HP from my 260HP and I was told this is a simple process and the price was going to be $450.00 to do this.

I test drove a 99 coachmen that had a reprogram and a high performance lift pump and it was simply amazing how it ran with little change in mileage.

No, these engines will not respond the "Dodge type" of engine controllers or add on's.

Insite is the only program from what cummings tells me that will allow one to up the HP from stock. Basically the ISB the 5.9's have a variety of different configurations/horse power ratings with the internals unchanged. The software shows the injector numbers and if these injectors need to be changed. I'm told the 350 HP file will use the same injectors as the 260 HP engine. With a diesel getting more power isn't too complicated. Simply add fuel and change the timing. Same turbo and nothing added except a "Good" lift pump. So, roughly $1050 would cover and aftermarket lift pump that I would install and $450 for the engine file.

Anyone done this?

BigLar368 · 10-24-2018, 07:26 AM

I would be willing to guess that there are a ton of things you can do to an ISB Cummins as they are basically the same engine used in 3/4 ton trucks. Bigger lift pump just supply more fuel so it does not starve the injection pump. When you tune the engine for more power it will require more fuel that's why you would need the lift pump. You can do some digging here and see what others have done. I bet you will find more information than you can handle....lol. Good luck.

jimcumminsw · 10-24-2018, 08:15 AM

I would be concerned if your transmission in your coach could handle the additional HP and TQ that a modified engine would put out. I believe the transmission and drive train are the limiting factors when a coach builder orders an engine from Cummins. They will build what ever the coach manufacture wants.

Coachmen Joe · 10-25-2018, 06:15 AM

Thanks for the reply. From the information I have been able to obtain my transmission was available with the higher HP engines. The Allison transmission is a very tough transmission and I'm not boosting the torque and HP above the limits of this transmission.

Coachmen Joe · 10-25-2018, 06:21 AM

Quote:

Originally Posted by BigLar368

I would be willing to guess that there are a ton of things you can do to an ISB Cummins as they are basically the same engine used in 3/4 ton trucks. Bigger lift pump just supply more fuel so it does not starve the injection pump. When you tune the engine for more power it will require more fuel that's why you would need the lift pump. You can do some digging here and see what others have done. I bet you will find more information than you can handle....lol. Good luck.

Thanks for the reply. Yes, I am fully aware of the need and reason for putting on a better bigger lift pump with the ability of more pressure and volume. That is why I mentioned it in my post. Yes, diesels are very easy to obtain more power and most of the time its as simple as add more fuel. The simple thing about the 5.9 ISB engine is its ability to go from say a 260 hp engine to 340 or 350 with a simple engine file. No need for bigger injectors because they are the same on the higher HP ISB 5.9 engines.

BigLar368 · 10-25-2018, 07:04 AM

Quote:

Originally Posted by Coachmen Joe

Thanks for the reply. Yes, I am fully aware of the need and reason for putting on a better bigger lift pump with the ability of more pressure and volume. That is why I mentioned it in my post. Yes, diesels are very easy to obtain more power and most of the time its as simple as add more fuel. The simple thing about the 5.9 ISB engine is its ability to go from say a 260 hp engine to 340 or 350 with a simple engine file. No need for bigger injectors because they are the same on the higher HP ISB 5.9 engines.

I bet even more can be obtained if you do a lift pump and possibly an exhaust. I would stick to what the transmission can handle. Don't be surprised if after you get it done it gets even better MPG if you drive it normally.

Coachmen Joe · 10-25-2018, 03:50 PM

Quote:

Originally Posted by BigLar368

I bet even more can be obtained if you do a lift pump and possibly an exhaust. I would stick to what the transmission can handle. Don't be surprised if after you get it done it gets even better MPG if you drive it normally.

Thanks for the reply.

The lift pump will be the first thing I will do. After the lift pump the engine file change. My motor home has a very large diameter exhaust system on it now and I think it will be fine considering its the same as the 330 hp and higher output engines. I think going from 260 to 350 hp with the increased torque will make her climb the mountains better. I think I'm going to stop there otherwise I'm going to want to do an engine transplant.

BigLar368 · 10-26-2018, 09:12 AM

We have an ISC 350HP and I recently installed a dedicated lift/fuel pump. On an ISB I believe the lift pumps run all the time. On most ISC's I have seen the lift pump runs only 30 seconds at start up and the injector pumps drafts fuel the rest of the time. Doing lots of reading that was a weak spot on my years model ISC so I installed a FAST pump with filters in the pump housing. I also did that with the intention of having a tune installed later and having the full time lift pump always helps.

Coachmen Joe · 10-27-2018, 12:15 AM

The purpose of the lift pump from what I understand is to draw diesel from the fuel tank. I believe it runs all the time on any engine.

Winemaker2 · 10-27-2018, 07:19 AM

Which Allison model do you have. I believe the 2500s were used up through the 350 hp versions of ISB. 3000 in the 360 hp ones. Torque is the limiting factor vs hp.

BigLar368 · 10-27-2018, 07:27 AM

Quote:

Originally Posted by Coachmen Joe

The purpose of the lift pump from what I understand is to draw diesel from the fuel tank. I believe it runs all the time on any engine.

I used to think the same but found that on our ISC (and most all other ISC's) the pump only runs for a short amount of time to prime the system then the injector pump takes over and drafts fuel. I think this is a bog problems with ISC's and that's why I installed a full time pump. This is our first trip using it and so far so good. Mileage is a tad bit better.

Coachmen Joe · 10-27-2018, 06:37 PM

Whether you own a Power Stroke, Cummins, or Duramax-powered rig (or something else altogether), a lift pump can simply be defined as a low-pressure supply pump that is used to transmit fuel to a high-pressure pump. In the case of most mechanical engines, fuel pressure is fed to an injection pump, where it is ramped up to more than 15,000 psi through the injection pump and injector. In the case of newer, electronically controlled trucks, a high-pressure pump (CP3, CP4, or Siemens) creates the pressure (in some cases more than 30,000 psi), which is then fed to a common high-pressure fuel rail, and then the injectors are used to meter injection events. In either variety, keeping steady pressure available for the high-pressure pump is vital to the engine’s performance.

This is the purpose of a lift pump. If the engine is running the lift pump is supplying fuel to the high pressure ECM controlled fuel pump that supplies fuel to injectors and thus to the engine.

That is the importance of the lift pump. Don't believe me? Try unhooking your lift pump and see how long your $1000.00 electronic fuel pump lasts.
Simplified, the lift pump draws fuel from the tank its only purpose and it sees to it the electronic fuel pump doesn't lack for volume and pressure. I sincerely doubt the lift pump is only used as a priming unit for a short time only.

BigLar368 · 10-29-2018, 11:36 AM

Quote:

Originally Posted by Coachmen Joe

Whether you own a Power Stroke, Cummins, or Duramax-powered rig (or something else altogether), a lift pump can simply be defined as a low-pressure supply pump that is used to transmit fuel to a high-pressure pump. In the case of most mechanical engines, fuel pressure is fed to an injection pump, where it is ramped up to more than 15,000 psi through the injection pump and injector. In the case of newer, electronically controlled trucks, a high-pressure pump (CP3, CP4, or Siemens) creates the pressure (in some cases more than 30,000 psi), which is then fed to a common high-pressure fuel rail, and then the injectors are used to meter injection events. In either variety, keeping steady pressure available for the high-pressure pump is vital to the engine’s performance.

This is the purpose of a lift pump. If the engine is running the lift pump is supplying fuel to the high pressure ECM controlled fuel pump that supplies fuel to injectors and thus to the engine.

That is the importance of the lift pump. Don't believe me? Try unhooking your lift pump and see how long your $1000.00 electronic fuel pump lasts.
Simplified, the lift pump draws fuel from the tank its only purpose and it sees to it the electronic fuel pump doesn't lack for volume and pressure. I sincerely doubt the lift pump is only used as a priming unit for a short time only.

My 2007 Duramax does not have a lift pump and it runs just fine. Not all diesels have lift pumps.

noserider · 11-03-2018, 11:09 AM

Quote:

Originally Posted by Coachmen Joe

Did a search first and didn't come up with anything. Anyway I purchased a 2002 Coachmen Cross Country with a 260HP engine. This thing is anemic and that is being kind. I had problems with simply not enough power going thru the mountains north of Phoenix. I have been told that one can simply go to their Cummings dealer/shop and have the engine file changed. I would like to go 330HP or 350HP from my 260HP and I was told this is a simple process and the price was going to be $450.00 to do this.

I test drove a 99 coachmen that had a reprogram and a high performance lift pump and it was simply amazing how it ran with little change in mileage.

No, these engines will not respond the "Dodge type" of engine controllers or add on's.

Insite is the only program from what cummings tells me that will allow one to up the HP from stock. Basically the ISB the 5.9's have a variety of different configurations/horse power ratings with the internals unchanged. The software shows the injector numbers and if these injectors need to be changed. I'm told the 350 HP file will use the same injectors as the 260 HP engine. With a diesel getting more power isn't too complicated. Simply add fuel and change the timing. Same turbo and nothing added except a "Good" lift pump. So, roughly $1050 would cover and aftermarket lift pump that I would install and $450 for the engine file.

Anyone done this?

I have a ISB 5.9 300 HP. Not sure if my 300HP is more powerful ( I think torque is the key) but I have pulled a toad close to 5000lb thru some decent grades without issues. I have the Allison 3000. Don't get me wrong it's not a beast for sure

but with proper rpm's on grade it's done well. Just wondering if yours is performing to spec. I did upgrade my lift pump to an Airdog Raptor for good measure. Please report back if you do upgrade the file and how that worked out for you. I don't believe I have heard of anyone doing this other than adding a Banks Kit. $450 for some more torque/horsepower sounds like a bargain. I'll sign up for that!