Ram HD 1000 lb-ft MPG loop

RoyJ wrote:

Still waiting for you to show me evidence the same engine at 500hp with no life reduction over a 200hp variant, which defeats every engineering principal. I'm guessing you have a big fat zero

Still waiting? Where did I say I will show you evidence in the first place. I went back though out our conversation and didn't see a single point where I said this so i am not sure what your are seeing. However, if you want to go down that road, I can say the same to you to provide evidence of what you say is fact. You can't just as much as I can't.

RoyJ wrote:
Saying B50 and B10 together is redundant - throwing tech jargons doesn't make you sound smarter...

Tech jargon? B10 and B50 percentages are what is used in the manufacturing world to measure an engines reliability given certain variables. If you are discussing an engines reliability under certain conditions or load(which we are) then they apply. I am sure that using Google to look up "what is B10 engine life" to know what I referring to

RoyJ wrote:
Did I say I don't understand how variable geometry works? Or that I need a lecture on it?

I asked you to back up your statement that 2 of the same engine, with the same VG turbine + compressor, why the lower hp version won't live longer.

Hold on. let me go back......Nope, not once did you ask to back up anything so that statement is false. Again, of you want to go down that road then I can and will ask you to back up your statements and you will not be able to as well since they are based on theory and not fact.

RoyJ wrote:

Do you agree since the compressor is the same, at lower hp we're operating at a lower pressure ratio? Do you agree a lower pressure ratio means lower EGT with the same intercooler? Do you agree lower EGT, plus lower intake air mass / density, means lower EGT and therefore longer life? If you say no I want to see equations backing it up...

No, I don't totally agree. Because just like the video link I posted stated, a restricted VG turbo has more drive pressure(back pressure) than a a correctly fixed FG turbo even with the same compressor size. The reason for higher EGT's is because their is not enough air for the amount of fuel being injected which is generally due to the VG turbos restrictive turbine side, not compressor side. A turbo with a higher CFM will reduce EGT's at the same load and will also require lest boost pressure t achieve the same power output.

However, stock VG turbo's are used primarily for emissions purposes even though their high drive pressures and EGT's reduce the reliability of the engine. In instances where the Cummins 6.7L does not have to meet such strict emissions requirements, a fixed geometry turbo is used like the one on e the marine 6.7L that achieves 550 hp and 1,250 lb-ft.

You also do not know what the internals of these engines can handle and I have seen what they can reliably. If an engine's internals can handle say 800 hp reliably due to its design and build quality, then putting 550 hp versus 200 hp will have no effect on these internals. This is what I am trying to tell you by talking about the turbo. It and the amount of pressure and volume from the HPFP is the limiting factor in reliability at higher power power numbers while also meeting emissions. The internals can reliably handle way more than what these two are capable of in stock form.

RoyJ wrote:
A good engineer always backs up statements with principals, calculations, laws of thermodynamics, etc. A bad engineer, or tech, relies on "years in the industry" in the absence of sound reasoning.

Okay, well then back up your statements because all I am seeing is a bunch of assumptions based on nothing.........