View Full Version : N-14

05-10-2009, 03:17 PM
Anyone run an N-14. I have a 460 hp 1650 ft lb rated one in a '95 T-800 with 13 double over w/ dual cleaners and dual 6" straights with a resonator 12" long. I would like to throw a FASS on it as well as a manifold from Pittsburgh diesel but we just use her around the farm and don't put too many miles on. She'll bury the 35psi boost gauge. Any other easy mods for power and MPG?

We have an LTL 9000 ford with a 400 Cummins in it. We put the dual line kit on from Pittsburgh diesel and it made a big difference. We fabbed up our own line on our tractor with an 855 and now she really pulls. The tractor also has a FASS on it which helps a lot too.


05-11-2009, 05:05 AM
I've had a couple of them. They are hard pullers and do a much better job than ISM's or ISX's. Parts are a problem where I lived - had to be special ordered. We put one into a commercial barge unit, that my buddy and I use on the Illinois River.

05-11-2009, 08:37 PM
I have N-14 in a 1986 Peterbilt 359.

05-11-2009, 08:58 PM
i had a chance to get one but man i should have thrown that in my box truck instead! Darn it !

05-12-2009, 04:34 PM
Cummins should be able to set it at 500 I think, we have just about the same truck, just a year or two newer, and it was a 460 they set at 500.

05-13-2009, 06:14 AM
I have N-14 in a 1986 Peterbilt 359.

You probably have a 444. The N-14 was not introduced till the early 90's.


05-14-2009, 07:24 AM
I pulled a BC400 out and put the N-14 in

05-16-2009, 09:19 AM
I had an N-14 same specs, 460, 1650, they turned it to 525 1850 no problem, and made a big difference.

06-06-2009, 08:17 PM
the N-14 was introduced in the 80's. i rebuilt an 1980 N-14 in a diesel program i took at a junior college near me. Serial tag 1980 right on it. it was only a 230 motor IIRC, but my buddy and i played with the pump and changed the button, put it on the engine dyno and pulled 265 out of it with about 1000 ft lbs. what a beast! sounded good running straight out of turbo too.

06-07-2009, 09:10 AM
I can't turn mine up anymore. It is just a Celect. The Celect plus came out in '96 and can be turned to 525hp. Not sure on all the differences but I have dual cleaners and dual straight pipes so she breathes good. It has more power than our neighbors N-14 in an IH with underhood cleaner and muffler. I wouldn't mind trying some Pittsburgh power mods like a FASS or an exhaust manifold. That would bump it up 50 hp or so.

06-07-2009, 10:36 AM
I was of the opinion that 1991 was first year for the N-14. Makes me wonder if the 1980 you saw was the CPL #, but there may have been some made for industrial purposes early on.

06-07-2009, 06:19 PM
wasn't the cpl i saw, i can guarantee you that. i couldn't tell you if it came off of a genset or what. but i recall the fuel lines entered and exited the rear head, so that tells me it possibly came out of a cab-over.

06-07-2009, 09:09 PM
The fuel lines(supply and return) on the 855 SC and BC engines and the N-14were that way. One of the improvments for more pulling power for these engines was to run an additional fuel supply line to the front head.

06-13-2009, 03:52 PM
I have 2 cummins Big Cam 3s set at factory 400 hp in a 85 and 86 Petes. Isn't the N-14 a computer driven engine??????? I never saw one until the early 90s. I can't find anything on them before 91. I have several Motors Heavy Truck Repair Manuals and nothing in them before 91 so I don't know.

06-14-2009, 05:59 PM
We have a 90 freightliner with what visually appears to be an N14, but there is no indication in the truck or on the engine that it is an N14. I have been told by a few people that 91 was the first year for the N14. The only reference to the engine i have found was in a brochure i found under the bed in the bunk , that referred to the engine simple as " red head 460".

06-14-2009, 08:42 PM
The N-14 I have, does have a manual injection pump and step timing. They are kinda rare. Mine has N-14 in big letters on it, I think it is on or near the thermostat housing. The horsepower rating on the engine plate says 330 hp. Had the pump built along with a Cummins V/12 supply pump installed on it. Got injectors for a 430 hp N-14M and had those increase by 15%, also have the turbo for a N-14-525hp and 220 lbs of fuel pressure .