Forum Discussion
184 Replies
ShinerBock wrote:
Because you keep saying that power levels are what they are due to reliability and that is not true. They are detuned to meet emissions just like gas engines were in the 70s and 80s.
For the hundredth time, because passing emissions is a GIVEN. You don't sell cars without doing so first.
GM discontinued the LS7 because they couldn't meet C7 Z06 performance targets. Obviously if they cheated on emissions they could, but that's a GIVEN.Because they can't reach those power levels AND meet emissions as I said before. Each use for the engine has different emissions requirements which is why the on road version of the 6.7L does not go above 385 hp yet the marine version of the 6.7L makes 550 hp with the same rods, crank, block, etc aside from things such as turbo and other devices the onroad version has to use to meet emissions. Sea water is also used to cool intake air which greatly increases power. The marine version still has to meet emissions, but they are different emissions that are not as strict as what on road and other uses.
Cummins 6.7L for Boats and Trucks - Compare and Contrast
If you want to talk marine specs, I can go on all day. Cummins is very specific about how long each power level should be used for, and at what vessel weight, and how to prop for each weight.
Point? All about longevity at a given duty cycle.
And before you say it again, yes, meeting emissions is a GIVEN.Here is the video at 3:43
Why are the 4500 and 5500 rated for less horsepower and torque?
The important part? Passing emissions as a result of LOADING. In other words, duty cycle (how much and how long an engine is loaded for).
It is not because chassis trucks, or class 8 trucks have tighter emissions. But rather, because of their higher loading, it's tougher to meet the SAME emissions.
So guess what happens if you met chassis cab emissions while making 385 hp? Surprise - the engine won't meet longevity targets!Because duty cycle, GVWR, displacement, and how the vehicle will be used plays into what emissions tier and bin the engine has to pass.
This link will explain further (LINK)
Now I know you didn't even read what the PDF said.
Every power rating is based on the assumption of passing emissions, the ONLY difference is loading conditions (aka duty cycle).
There's no difference in "emissions tier" in Cat's duty cycle ratings, that's a constant factor.Going back on your first few posts, you did not mention emissions or say it was a "given" until I explained it. Without the emissions requirements, the engines can make way more power. Again, similar to back in the day where you could have gotten a lot of power out of the old 70s and 80s cars by removing emissions devices and limits.
I also didn't mention the truck has to pass modern crash tests, have air bags, or ABS/traction control. Because they're also a GIVEN. You don't sell a vehicle without it.
Audi's SQ5 also had revised heads, pistons, and turbos, just to squeeze out 20 hp over a standard Q5. Oh, did I mention they have to do so while meeting emissions?
No, because it's a GIVEN.The old crank and rods can easily hand 800+hp. That is proven. The heads and turbo(which is the same for the most part) was probably adjusted for more air to allow for higher power numbers while staying with emissions. You also have future power numbers. Cummins will no doubt increase power levels to keep up with competition just like they did from 2007.5 to 2018. All they did was adjust tuning and add emissions devices that allowed them to go from 350hp/610lb-ft to 385hp/930lb-ft. They didn't change a thing to the engine itself.
It's proven to handle 800+ hp in tuner applications, low duty cycle and low longevity applications. My point since the beginning.
It's NOT proven to withstand 800hp in line haul duty cycle. And before you say it again - yes, while meeting emissions...RoyJ wrote:
Because you keep on quoting emissions this, emissions that, as if I never took it into account.
Because you keep saying that power levels are what they are due to reliability and that is not true. They are detuned to meet emissions just like gas engines were in the 70s and 80s.RoyJ wrote:
Let's think logical for a moment - if an ISB can be tuned that high, what's the point of Cummins making an ISC, ISL / L9, ISM / ISX13?
If an ISB can make 400hp reliability, at any duty cycle, in any application, the you would see them in city buses instead of ISLs. You'd see them in vocational trucks. In 300 size excavators, dozers, etc.
Because they can't reach those power levels AND meet emissions as I said before. Each use for the engine has different emissions requirements which is why the on road version of the 6.7L does not go above 385 hp yet the marine version of the 6.7L makes 550 hp with the same rods, crank, block, etc aside from things such as turbo and other devices the onroad version has to use to meet emissions. Sea water is also used to cool intake air which greatly increases power. The marine version still has to meet emissions, but they are different emissions that are not as strict as what on road and other uses.
Cummins 6.7L for Boats and Trucks - Compare and ContrastRoyJ wrote:
While you find me a video
Here is the video at 3:43
Why are the 4500 and 5500 rated for less horsepower and torque?RoyJ wrote:
It's from CAT. On page 3, you can see how they have 5 classes of duty cycle, from continuous to very intermittent.
On page 18, using C15 as a random example, you can see it's limited to:
- 440 hp continuous
- 540 hp intermittent
- 595 hp occasional max
This is ALL assuming emissions targets are met. What I really want to hear from the Cummins engineer is: was duty cycle a consideration between pickup and chassis cabs?
Because duty cycle, GVWR, displacement, and how the vehicle will be used plays into what emissions tier and bin the engine has to pass.
This link will explain further (LINK)RoyJ wrote:
That's why I said to me emissions is a given. Therefore other than emissions reliability vs duty cycle is the predominant reason.
Going back on your first few posts, you did not mention emissions or say it was a "given" until I explained it. Without the emissions requirements, the engines can make way more power. Again, similar to back in the day where you could have gotten a lot of power out of the old 70s and 80s cars by removing emissions devices and limits.RoyJ wrote:
Getting back on topic, I stand by what I said - Cummins altered the block, piston, rods, head, and turbo just to gain 15 hp / 70 lb-ft RELIABLY.
If they didn't have to, believe, they wouldn't have. That's a lot of R&D that could have gone to executive Christmas bonuses, if they could just "turn up the boost" to squeeze out 15hp.
The old crank and rods can easily hand 800+hp. That is proven. The heads and turbo(which is the same for the most part) was probably adjusted for more air to allow for higher power numbers while staying with emissions. You also have future power numbers. Cummins will no doubt increase power levels to keep up with competition just like they did from 2007.5 to 2018. All they did was adjust tuning and add emissions devices that allowed them to go from 350hp/610lb-ft to 385hp/930lb-ft. They didn't change a thing to the engine itself.MikeRP wrote:
I had a 2008 Ram MegaCab 6.7L. My new 2018 HO one has a lot more torque. It sounds really cool, like a big old bull ready to kick your butt, the old one was, I thought, a beast in its own right with 350/550 numbers and it weighed just about the exact same as the new one.
Had about a 1800 lb payload, which we all know is bull **** just missing a leaf spring. My new one has a payload of 3870 lbs according to the door sticker. No doubt it is a safer more capable truck and I do think Ram does make a great fiver towing platform.
No way did a 2008 weigh also most the same as a 2018 model for model. ChrisRobertRyan wrote:
As I said you have a reading and comprehension problem. That is one issue the other you cherry pick what I say( similar to the issue RoyJ has with you) and Falsely misquote my posts. In other words ShinerBrock you are either a psychotic trioll or just a paid industry troll
How did I misquote you? You clearly said no demand which is false.
If you don't want me to call you out then stop lying just to **** on the US and our trucks like you normally do.RoyJ wrote:
Cummins12V98 wrote:
"I expect the new Ram to come in DEAD LAST in the next Ike run. Why? Because the Powerstroke and Duramax has consistently dynoed more, plus GM is getting the 9-speed. But that's my point, it doesn't mean the Ram has worse "towing performance". "
May want to do some research
2018 Ram 3500 HD vs Ford F350 vs World's Toughest XXL Towing Test!
RAM 11.41 seconds 2.7mpg
Ford 11.43 seconds 2.4mpg
ATS Dyno 2017
In model year 2020, big difference is GM / Ford has really stepped up their transmissions, while Ram still has a 6 speed. Would it over-come a 40 hp deficiency? Not unless Cummins seriously sand-bagged the numbers.
You dyno graph didn't show up. In every stock dyno I've seen other than TFL (their's is messed up), the L5P and Powerstroke soundly beats the Cummins 385.
But, that wasn't my point. The context is that Ram is a superior towing platform compared to the GM despite lower engine output.
I was looking at those dyno numbers and I don’t think if there was a way to do a blind test, that one could tell the difference in power between the trucks.
I had a 2008 Ram MegaCab 6.7L. My new 2018 HO one has a lot more torque. It sounds really cool, like a big old bull ready to kick your butt, the old one was, I thought, a beast in its own right with 350/550 numbers and it weighed just about the exact same as the new one.
Had about a 1800 lb payload, which we all know is bull **** just missing a leaf spring. My new one has a payload of 3870 lbs according to the door sticker. No doubt it is a safer more capable truck and I do think Ram does make a great fiver towing platform.ShinerBock wrote:
RobertRyan wrote:
You have a reading and comprehension problem
So how am I reading and comprehending this incorrectly?
You said there was "no demand" which is what I said was false. There is demand even though it is small demand due to how much our trucks cost and other variables.
As I said you have a reading and comprehension problem. That is one issue the other you cherry pick what I say( similar to the issue RoyJ has with you) and Falsely misquote my posts. In other words ShinerBrock you are either a psychotic trioll or just a paid industry troll
My original quotepart No demand for the point of view of the manufacturers very true indeed
FishOnOne wrote:
And what's up with that short dip stick. It looks like it will hit the cab
I'm pretty sure that is not the real dipstick, just there for the demo unit.Cummins12V98 wrote:
"I expect the new Ram to come in DEAD LAST in the next Ike run. Why? Because the Powerstroke and Duramax has consistently dynoed more, plus GM is getting the 9-speed. But that's my point, it doesn't mean the Ram has worse "towing performance". "
May want to do some research
2018 Ram 3500 HD vs Ford F350 vs World's Toughest XXL Towing Test!
RAM 11.41 seconds 2.7mpg
Ford 11.43 seconds 2.4mpg
ATS Dyno 2017
In model year 2020, big difference is GM / Ford has really stepped up their transmissions, while Ram still has a 6 speed. Would it over-come a 40 hp deficiency? Not unless Cummins seriously sand-bagged the numbers.
You dyno graph didn't show up. In every stock dyno I've seen other than TFL (their's is messed up), the L5P and Powerstroke soundly beats the Cummins 385.
But, that wasn't my point. The context is that Ram is a superior towing platform compared to the GM despite lower engine output.ksss wrote:
Using your analogy, a 379 compared to a T800 and Western Star or Mack of similar hp and torque running the Ike or some other similar test would provide an idea on towing performance. Comparing a 379 to a class three pickups would be silly. Comparing similiar class 8 trucks to EACH OTHER would provide SOME value. It perhaps would not give all the information a buyer would want but it would be much more information than looking at a spec sheet alone.
Let's do this then. 2 trucks:
- Volvo hwy tractor, with their 625 hp D16 and i-shift, spec'ced as light as it can be (13k front, 38k rear)
- Western Star tridem with double frame, 20k front, 69k rear. Conservative 500 hp ISX, 18spd fuller, say 4.10 rears
Towing the same load, which one will smoke the Ike Gauntlet run? You bet the Volvo would run circles around the heavy spec truck - more power, less weight, less parasitic drag.
Does that mean the Volvo is a better towing platform? No, it's simply faster with a lighter load. But you couldn't hitch up a heavy load and still ensure chassis longevity.
That was my point. The Duramax is the FASTER tower, not better. You and I both know if GM could slap on a 36,000 lbs tow rating the would in a heart beat, for sales.
We also agree it's not the Duramax holding it back, so what is? If not the chassis / axles then what's left, size of the glovebox?RobertRyan wrote:
You have a reading and comprehension problem
So how am I reading and comprehending this incorrectly?
You said there was "no demand" which is what I said was false. There is demand even though it is small demand due to how much our trucks cost and other variables.
