New RAM HD 1000 lb-ft

RoyJ wrote:

Perhaps I should've been more clear from the start - any time I say "the engine tune is maxed out", or "Cummins had to do hardware change to squeeze out 15 hp", I'm doing so under the assumption that it must pass emissions in the first place.

We all know the 2018 Cummins long block itself, if tuned to 1989 standards, can easily hit 500 hp, PLUS deliver 250k miles of reliable service. So I assumed it was obvious that meeting emissions is the very first requirement to even get out of the factory door.

I said this from the beginning so why do you keep rebutting what I am saying?

RoyJ wrote:
While different emissions certifications is one of the reasons, it's far from the ONLY reason you won't see a 385 or 400hp ISB from Cummins in commercial application. The predominant reason is duty cycle, a fancy way of saying it won't meet longevity targets at the intended use.

Actually in the case of 400 hp.... Yes, emissions is the ONLY reason why the ISB will not see 400 hp in a commercial application. You can run about 450-475 hp(390-415 rwhp) heavy loads all day long without running into to higher temps or reducing long term reliability. I have seen it in the tests cells when I worked at Cummins and I have seen it with the many hot shoters that I know who run this power level with hundreds of thousands of miles on their trucks.

Now if you were talking 500 hp(440 rwhp), then I would say yes that these power levels will start to reduce longevity with the stock turbo. You would probably be fine towing moderate loads, but heavy loads will cause temps to get to unsafe levels.

RoyJ wrote:
Pickups, RVs, and fire apparatus has the lowest duty cycle; this is where you see 350hp ISBs and 650 hp ISXs. Next would be a Class 4 / 5 truck, then school bus, then city bus / tour coach, then line haul trucks, then heavy spec trucks, then heavy machinery (be luck to see a 240hp ISB on an excavator), and finally gen sets, where you see the most conservative rating.

I know the medium/heavy duty market. I have worked in it for more than two decades. Should I find the video of the Ram engineer stating that the reduced power between the the pickup and cab/chassis trucks is mainly do to emissions certifications than duty cycle?

RoyJ wrote:
If you insist dyno certification is the ONLY reason behind a 200hp ISB genset, and 400hp pickup, you'll have to show me some Cummins documents stating so.

I never said this. Where did I say this? In fact, my exact words were "I worked at Cummins and can honestly tell you that while reliability is high on the list, it is not the most important thing, passing emissions is." Meaning that while reliability is high on the list when tuning an engine, it is not the main reasons. Meeting emissions is. You can still increase the power output(to an extent) from factory levels without reducing long term reliability.