Cummins NTA855 N14 PT pump pump size to fuel flow psi

[Roadoil]

Hello

I have heard the proper way to increase HP with a PT pump on a 855 or N14 is change the gear size on end

I have a NTA 855 1204 CPL factory was 335 hp to get to 500hp change out the gear pump from 3/4" to 1"? They also make a 1 1/4" gear pump maybe thats better?

Does the size 3/4", 1",1 1/4" inch mean the size of the gears so larger 2 gears meshing maskes more flow and psi?

This is a stationary pump application

 

[Truck Shop]

Not to be brash---But I won't touch this one with a ten foot pole.

 

[Roadoil]

Not to be brash---But I won't touch this one with a ten foot pole.

LOL Why?

I heard this from a reputable PT pump builder

 

[Truck Shop]

Compression ratio, cam and cam timing, injector flow and turbo just to name a few.

 

[cfherrman]

500 HP for how long?

 

[kshansen]

Not to be brash---But I won't touch this one with a ten foot pole.

Are you trying to say that something more than just putting a bigger gear pump would be needed to increase the horse power 50% of this Cummins?

Not to mention that if this is a stationary engine. It may be expected to run at this elevated output for hours at a time unattended would be much different that of a truck engine that might only be expected to put out that much for a short time when accelerating from a stop.

That also might have an operator sitting there watching the pyrometer climbing and possible have the brains to back off before the exhaust system is aluminized internally!

 

[crane operator]

I don't think any 855's made over 500hp (factory) until late N-14 with celect plus? Surely the idea that a simple PT pump setting, is going to take you from 335 to over 500hp, doesn't seem possible, or realistic? Especially not in a presumably necessary stationary application? I don't know much- but I know none of that makes sense.

 

[Roadoil]

Well i gave the shop my CPL 1204 he said bigger gear pump all it needs, he said its good for 600 hp before you start needing mods to keep it cool.

I asked if it needed a turbo mod he said no.

Perhaps certain builds are detuned to spec and can handle higher HP.

 

[Roadoil]

I don't think any 855's made over 500hp (factory) until late N-14 with celect plus? Surely the idea that a simple PT pump setting, is going to take you from 335 to over 500hp, doesn't seem possible, or realistic? Especially not in a presumably necessary stationary application? I don't know much- but I know none of that makes sense.

Not sure I have a N14 similar pump application stock 475 HP

 

[mitch504]

Well, if you change the size of the drive gear on the pump, you definitely have to change the gear it mates to, or change where the pump mounts to get the shafts farther apart.

Just for the record, I am skeptical of this for all the other reasons too. I think your guy was talking through his hat.

 

[Roadoil]

This pump a high pressure water blaster 20,000 psi was ordered to a specific flow back in the day 23 gpm that would be the 335hp.

Pump is the same for higher flow just used a higher HP motor to enable higher rpm of pump say to 26 gpm at 20k which would be a 350 HP motor.
Detune the motor to 335 hp only way to get that spec 23 gpm around 320 rpm vs 380 rpm higher flow 26 gpm and more hp to get it there

 

[Roadoil]

Well, if you change the size of the drive gear on the pump, you definitely have to change the gear it mates to, or change where the pump mounts to get the shafts farther apart.

Just for the record, I am skeptical of this for all the other reasons too. I think your guy was talking through his hat.

The pumps have identical housing and shaft different internal size

 

[mitch504]

You would also have to change the water pump gearing, because your crankshaft RPMs wouldn't automatically change, a higher hp engine would just be capable of turning the pump faster at the same pressure.

 

[Roadoil]

You would also have to change the water pump gearing, because your crankshaft RPMs wouldn't automatically change, a higher hp engine would just be capable of turning the pump faster at the same pressure.

What I am doing is taking the old Gardner Denver TF450 water blast pump off. It's a 350 HP pump 26 gpm max 20k output.
I am replacing it with a aqua dyne 500 hp triplex pump. It needs 500 hp to produce 20k water pressure and 43gpm

The PTO output and rpm will be the same but need that 500 hp to spin that pump to 320 rpm same as old pump but much larger plungers.

That 335HP stock power will only be able to run that aqua dyne pump to maybe 210 rpm and same flow 25 gpm

 

[Roadoil]

So what I am unclear of are the different spec pumps 3/4", 1", 1 1/4" have longer pump gears for more flow and higher psi ?

The builder said I have a 3/4" pump on mine.

I asked about the other mods they do throttle pressure screw and button mod he said they don't work as well as changing the pump gear.

 

[Truck Shop]

Perhaps certain builds are detuned to spec and can handle higher HP.

That's not how Cummins builds engines. Run the list of CPL's below and note injector #'s, Cam codes
and piston changes.

https://dai.com.au/docs/855-CPL-mat...QY6WO6AjpjCyHp_ncWb6YfV_E10DTG2nWyTJkJKP8jEvw

 

[Roadoil]

That's not how Cummins builds engines. Run the list of CPL's below and note injector #'s, Cam codes
and piston changes.

https://dai.com.au/docs/855-CPL-mat...QY6WO6AjpjCyHp_ncWb6YfV_E10DTG2nWyTJkJKP8jEvw

Ok

 

[mitch504]

Ok, I was working with 2 misconceptions, I for some reason assumed you wanted to drive the same blasting pump harder, a bigger pump makes sense.

The other, I got stuck on this paragraph:

"I have heard the proper way to increase HP with a PT pump on a 855 or N14 is change the gear size on end"
and I thought you meant the pump drive gear which definitely won't work.

I am still sure that just changing the gear pump also won't work for industrial use. If it would, that's the way it would commonly be done.

It would give you the capability to move more fuel, but to get it into the cylinders, you would have to have bigger injectors, just like your blaster won't move 43 gpm at 20k psi through the same nozzle it is using now.
Once you get the extra fuel into the cylinders, the only thing it would produce is black smoke without getting more air in, thus, different turbo.
To get that turbo's air into, and out of, the cylinders at the same RPM, the valves have to stay open longer, thus different cam.

This sounds a lot more like some youtuber's plan to get more power and smoke for a few minutes at a time for a show toy.

 

[mitch504]

This is a pretty good explanation of the PT (Pressure-Time) fuel system.

 

[cfherrman]

With that guy saying you could get 500 HP without changing the turbo or injectors is a big red flag.

To run that triplex you need a new engine unless the pressure or gpm will be less that you said.

Are you running this off a pto? This needs to be direct driven off a transmission.