Monaco cummins 315 hp, can i turn it up?

mmraceca · 06-12-2007, 06:33 PM

I have a 2000 monaco with a cummins 315 hp with a 6 speed allison. I pull a 34' enclosed race trailer and when i hit the big hills it needs more power. It's out of warranty so how do i turn it up safely? Thanks in advance, Justin

mmraceca · 06-12-2007, 06:33 PM

I have a 2000 monaco with a cummins 315 hp with a 6 speed allison. I pull a 34' enclosed race trailer and when i hit the big hills it needs more power. It's out of warranty so how do i turn it up safely? Thanks in advance, Justin

Gary M. Smith · 06-12-2007, 07:17 PM

Justin, with a coach and a 34' enclosed trailer (I assume a car and equipment inside), you probably are running pretty darn heavy. A call to Gale Banks Engineering might net you some information on what's possible. Try the test report number at 1-888-294-5231.

mmraceca · 06-13-2007, 06:01 PM

Thanks Gary, I was looking for an affordable way to increase power. I think i found it. I called Cummins and they can reprogram the ecm and go from 315 hp and 950 torque to 350 hp and 1050 torque. The local cummins dealer will do it for $250. I going tomorrow afternoon, Justin

J Walker · 06-14-2007, 04:30 AM

Justin, Calling Cummins is the way I would have gone if only to insure that the power increase would not over stress the engine. You should have a look at the transmission specs to see that the HP and torque will be ok which it probably will be. One other thing is the weight of your trailer. Have you looked at the capacity of your hitch? The way it is mounted to the frame and the frame itself are big questions. I can't imagine that the stock hitch would come close to meeting your requirements.

ghamblen · 06-15-2007, 05:00 PM

We have farm equipment with both the Cummins and CAT engines. We have had the service techs turn them up once out of warranty and have had no problems so far. The power gain is easily felt and the fuel useage seems to be about the same although we are more interested in power when pulling heavy equipment in the fields. The techs say they have turned them up on about a third of the ag tractors they service and have not encountered any problems to date. If you have them turned up by the OEM or a service tech I don't think you will have a problem because they will keep them in a band that will not hurt the engine. They don't want the hassle or lost sales they will get from farmers if these engines start having major problems.

mmraceca · 06-17-2007, 07:46 AM

Well i had a bad luck trip, when i got to cummins they hooked up to the bus and looked up the motor with all the # and cannot upgrade the program. I have one of the handful of systems that is maxed out already. But good news and bad is we found a exhast leak. He said the power would be improved a lot when fixed. Anyone out there got a 2000 diplomat or equal with a boost gauge let me know how much boost you get up hill? I am only getting 11 lbs and the cummins guy said it should have 20+. Thanks, Justin

FW · 06-24-2007, 11:38 AM

Justin; Mine new to me about 2 months ago always gives me 20+ boost going up a hill.
I'm still learning about this new DP life.

mmraceca · 06-24-2007, 09:34 PM

FW, so you do get that much boost, well good deal. It is going to the shop in the morning to get the new gaskets. Hope this is a big help on power. I love the motorhome, Monaco builds a nice piece, Justin

mmraceca · 07-08-2008, 06:09 PM

well over the year, i have put off doing anymore to the boost. Since i fixed the gaskets, it went up from 10 to 16 psi. It is all it will do no matter how big of a hill or load. My question now for everyone is what is there to check or do for loss boost. I was told by someone it should have boost at a idel. Mine is 0 or lower almost a slight vaccum. Thanks in advance for any help, Justin

Panbob · 07-22-2008, 04:52 PM

Hey Justin, older diesels had a "waste gate" to control over boost. Modern diesels have a turbo boost control valve that is controled be either electricity or air. Should be behind turbo with a lever going into it. It could be that this is not opening up to allow full boost. My Cummins 450 gets up around 27-28lbs boost.

cannon man · 07-22-2008, 06:18 PM

had an 02 monaco with the 315hp c series.
full load was always 22 or 23 #. maybe your turbo could use a rebuild or you could have a restricted exhaust downstream of the turbo. good luck. my c series pulled like a tractor up any hill.

oldvectra · 07-26-2008, 08:27 AM

You need to make sure that there is no leak in the intercooler and the hoses that connect it to the intake. You could be making more boost just losing it from a leak.