Cummins horsepower

[bamaboy473]

Originally Posted by DD788Snipe

Some of the 350s had wrist pin issues and there was a recall on some, not all, of the those engines..

400HP engines were on that list as well. Here are the ESNs:



ISL CM850 recreational vehicle ESNs eligible for this campaign range from 46543077 to 46603939.

[Bucky1320]

You know that everyone had their opinions. But I don't think we even know yet what you are planning for this motorhome. Towing? How much? Where do you live and where do you plan to travel. We do most of our motorhome usage in Illinois with a 38'er and a 9000 lb trailer behind us. And the CAT 3126 is great for that with plenty of power AND braking. But that is in fairly flat countryside. 300 hp is no sweat for it. But going up a mountain? That's going to take the wind out of it big time. Weight of the motorhome is also a huge factor. Mine is way lighter than some of the rigs built today. 40,000 lbs? You are going to want some umph for that. For a lot of racers that pull trailers, the 8.3 has proven to be both powerful enough to get the job done, and somewhat economical to operate. That was probably my first choice for powerplants.

[Ramets]

Don't get hung up on HP. With a diesel it's torque. The old saying is torque gets you going, HP keeps you going.

[Gary RVRoamer]

The old saying is torque gets you going, HP keeps you going.

LOL. And no more (or less) true than when it was a young saying. Since torque and HP are mutually dependent on each other, if you have more torque you also have more horsepower. The math says it: HP = Torque x RPMs /5252

The advantage of a diesel is that it produces a lot of torque at low rpms, so you actually get plenty of hp when accelerating from a stop or climbing a hill. Gas engines produce their torque at high rpms, so most of the time you don't have the full rated horsepower available for use.

[JohnBoyToo]

Originally Posted by DD788Snipe

..... I plan on getting the ECM reflashed to up my HP and torque after this trip. .... The ISL was produced with 350, 370, 400 and 425 HP.....

I have heard of reflashes for the rv, but not sure where/how to pursue that... and wondered if I could for the new to me cummins 425...
(I came from the diesel pickup world and have experienced the large safe gains of tuning)

The biggest issue I have is this is the first DP I've owned and I know relatively NOTHING about the rv, just learning and loving it so far !!!

Thanks in advance !

[zman-az]

If you look at the current freightliner 34 and 36' models you will see a difference in hp with the same cummins. The 34' models use the smaller Allison and it has less load capacity. In order to not damage the Allison they cut back the torque and hp of the cummins in the 34' models.

[Ted Lambert]

Originally Posted by Bucky1320

You know that everyone had their opinions. But I don't think we even know yet what you are planning for this motorhome. Towing? How much? Where do you live and where do you plan to travel. We do most of our motorhome usage in Illinois with a 38'er and a 9000 lb trailer behind us. And the CAT 3126 is great for that with plenty of power AND braking. But that is in fairly flat countryside. 300 hp is no sweat for it. But going up a mountain? That's going to take the wind out of it big time. Weight of the motorhome is also a huge factor. Mine is way lighter than some of the rigs built today. 40,000 lbs? You are going to want some umph for that. For a lot of racers that pull trailers, the 8.3 has proven to be both powerful enough to get the job done, and somewhat economical to operate. That was probably my first choice for powerplants.

I plan on getting as many opinions that I can. Also I would not consider cat. I had to change my truck fleet over as cat's were nothing but trouble. I know people do like them but everybody makes there choice.
How can a person tell what their usage will be from year to year?
I have traveled a lot of miles in the cab of a truck and there are places from the Yukon to Florida. That I would like to spend time at.

[Mr_D]

Originally Posted by Steve Ownby

The biggest shortcoming of both Cats and the ISC is they aren't available with a compression brake which performs much better than the exhaust brakes. That's a big plus for the ISL. all of these engines will be paired with an Allison 3000 transmission.


Steve Ownby
Full time since '07

Not all ISL's have a compression brake, some did come with exhaust brakes.

[DD788Snipe]

My ISL came with a Jacobs exhaust brake and it works fine. Sometimes, at low speed, almost too good.

[Mr_D]

Originally Posted by Gary RVRoamer

You don't get to pick the engine & tranny in a coach, even when new, so it is what it is. Most will be Cummins and Allisons, and the Allison 3000, coupled with the Cumins ISC or ISL are the reliable work horses.

Well, yes you can or at least could. In the Magna we just bought you could get three engines and two transmissions. Standard was a 600 HP CAT and CAT trans, the next was a 600 HP ISX Cummins with Allison 4000MH and then the 650 HP ISX Cummins with the Allison 4000MH.
However, in most cases you're right. Usually it was in the Beaver, Monaco or Country Coach that you had a choice.

[Ted Lambert]

Originally Posted by Gary RVRoamer

LOL. And no more (or less) true than when it was a young saying. Since torque and HP are mutually dependent on each other, if you have more torque you also have more horsepower. The math says it: HP = Torque x RPMs /5252

The advantage of a diesel is that it produces a lot of torque at low rpms, so you actually get plenty of hp when accelerating from a stop or climbing a hill. Gas engines produce their torque at high rpms, so most of the time you don't have the full rated horsepower available for use.

I could not agree more.

[Lued]

I have a Cummings 8.3 ISC 330 HP with the Allison 3000 does a fair job, pull a Jeep Cherokee .