How does this affect the torque?
If it doesn't reduce it too much this could be great for other uses such as construction.

James -

if there is construction equipment out there with the exact same engine and its operators are prepared to make do with the lower power rating, then it would indeed be technically possible to apply this software change.

However, when you pay for a 5.9L engine in a commercial context, it's usually because either you need the power or you have few other choices. The latter apparently applies in the very special case of mine operations, where electric vehicles are problematic due to the fire hazard - the atmosphere in many mines contains methane outgassings from the seams.

Does the engine actually purify the air by burning the methane outgassings?

175hp is plenty for construction work etc if there is a decent slab of torque there.

Horsepower and torque are tied together. If we knew at what rpm this 175 HP is derived at, we can figure torque. (HP X 5252, divided by the rpm.) With the mine speed limits, the rpm should be low, perhaps? Theres alot we dont know here.

But tuning this engine for minimum emissions would seem, to me, to most likely make this engine less efficient. Any formulas to support this? If not, then every Cummins 5.9 on the road should be thusly (sp) remapped this way. Would this engine thusly remapped meet the upcoming, tight, 50 state legal diesel emission standards, without urea injection?

if detuning the engine to that level is required to meet the upcoming emission standards then there would be no advantage for somebody to pay the extra money over a gas V10 or whatever other gasoline engine option is.

H-H-H-M-M-M-m-m-m- I wonder if this remapping thing could evolve into a switch on the fly thing that if you needed the full 325 HP for towing or hauling a full load then you just flip the remapping switch and if you were just tooling around going for job site to job site and 175 HP was acceptable you could just flip the remapping switch to reflect necessary HP and reduction in emissions (and corresponding reduction in operating expense??) -- need to know more about how it works.

Maybe not, it might be like the Atkins cycle were a different cam is needed. Unless the engine has vvt which I don't think the cummins does.

"...you just flip the remapping switch..."

If that is allowed, then what is the point in having emissions control? For once a year, everyone can flip a switch and get the best emissions possible, but then the rest of the year, they would just pollute all they want for the sake of maximum horsepower.

In all probability a MSHA approved setup is far, far more costly than the standard setup as they would like to recoup the laboratory costs from validating their engine and time spent re-engineering the firmware. My company sells TSO and non-TSO equipment and there is no difference between the two except for the fact that the TSO equipment had to be laboratory certified and thus the cost for TSO equipment is higher even though it functions in an identical manner to non-TSO equipment.

Considering it says the engine is mechanically the same as the 325hp version, it likely just runs lower boost. It should hit that power peak no later than 2500rpm, which would equate to having around 367 ft-lbs at that engine speed. I don't imagine you get much over 15 to 20mph in a mine at that absolute most, so having more power and torque than that probably isn't needed.