Cummins Big Cam Power Upgrades NTC 855 N14

[ethan93]

Hi everyone, I am new to the big cam world and Cummins cpl system etc.

I have a 1990 Kenworth K100E with a N14 Mechanical NTC-365 rated at 375hp.

Purchased the truck last year and has been awesome transporting our digger around and carting gravel, have since put a gravel trailer behind the old girl and although she still pulls good it just doesn't quite have the steam with loaded truck + trailer.

I am wanting to add a bit more power and take it out to the 400-420hp range if possible?

CPL is 904
Technical Engine Configuration # D093546BX02

What is required to get this up to the 400-420hp range? Fuel pressure/Fuel Button, Timing, Are the cams different between engine configurations based on hp range? Any help would be greatly appreciated, not many old school Cummins techs or people of knowledge around where I am.

 

[DMiller]

Is nothing cheap as to boosting hp on these, and yes, cam timing, pump changes, possibly piston change. On that style cab doing anything in frame is not going to get what you want.

 

[ethan93]

Is nothing cheap as to boosting hp on these, and yes, cam timing, pump changes, possibly piston change. On that style cab doing anything in frame is not going to get what you want.

Thanks mate, have seen some guys on youtube swapping out to a smaller fuel button and upgrading to a newer N14 turbo. Any of which worth doing? Other option is wait until rebuild time and pull engine then build to a higher hp cpl

 

[DMiller]

There is in actuality nothing that is a bolt on going to do what you want or wish without creating more issues. Having someone with the tooling to just run the overhead may restore some values of base horsepower.

Are no magic bullet mechanisms to adjust HP ranges.

 

[Shimmy1]

Thanks mate, have seen some guys on youtube swapping out to a smaller fuel button and upgrading to a newer N14 turbo. Any of which worth doing? Other option is wait until rebuild time and pull engine then build to a higher hp cpl

If you already have a 13 speed, anything below 75-100 HP will not be noticable. Twenty to forty horse will just burn more fuel. Like DM says, run the rack, change the fuel and air filter, if it smokes a bunch, it's probably ready for injectors. If Truck Shop feels like commenting on here, you will know more, but from all the threads posted over the years, it seems likely that you will need a different cam and cam timing in addition to higher rail pressure to get more HP. That tells me that the added horsepower will also be accompanied by an increase in torque, which is actually what you're looking for.

 

[Truck Shop]

CPL 904 is technically a New BCIV, the N14 was started in 87 and went into production in 1990.
A photo of it and data plate located on accessory drive housing would be good. Does this engine
have air charge cooling?
*
The reason for asking for the above information is the break period when the N14 went into
production. But one thing about the N14 Mechanical there is many options for large torque &
horsepower gains, some of it requires piston change, but a N14 Mechanical can be built with
horse power not seen in other 855's. Because two piece iron top pistons can easily be had for
N14 but not the earlier BCIV & NT88's.
*
If it is a BCIV there is only so much that can be done and still have reliable power. The N14
used the same turbo through out it's upper horse power ranges-#3804502. It spooled up
much sooner. Big thing is all New BCIV's through the mechanical N14 were STC, step time control.
The max safe level of percentage overfueling is 15% which puts rail psi @ around 200/205.
Past that and stress to injector lobes climbs out of sight, your stock pump is probably set @ 165.
A safe level nets about 455 hp for earlier engines a N14 {M} can be boosted to 550 real easy.