turbo on a NHC 250 Cummins?

[Cowboy_Customs]

Same question, will do some research but sense I am already here....

Which Cummins engines are compatible with the 250? Heads, turbo intakes, jakes...... Thanks guys any info is appreciated!

 

[m16ty]

I've got a 250 with a turbo on it. I'll take some pics and post it. I may consider parting this engine out.

Just about any Jake Brake for a Cummins will fit. If you find one on any 855cid Cummins will work. I don't think you can shut the hood with the Jake Brake installed without some hood modification though.

These engines are basicly the same as most other Cummins engines untill Cummins went to a overhead cam a few years ago. The design and displacement is the same as a modern day 600hp engine.

 

[grounded]

TY if you go to sell the turbo setup or any other stuff for the 250

PLEASE LET ME KNOW FIRST!!!!..

 

[Flea]

FWIW, I think Jwaller has put a turbo on his truck as well, an 818. He's got a writeup around here somewhere detailing how it was done.

 

[cowhauler185]

the rural fire fighters in Wy have at least one such truck, have driven it and it has been in use for several years with no problems, the only changes I can see are the crossover tube cutout in the hood and the air cleaner to the right fender,, don't know much about it otherwise, a long time ago we put what they called an ecology blower on a reguler small cam 250, no other changes, our altitude here is 5- 75 hundres feet, density can get over 10 in the summer, the one we used helped with that,,

 

[goldneagle]

3 PAGES AND NO PICTURES!

 

[vinny-socom1]

You can put a turbo on the 5ton with mods, I have seen it done with parts from a 290 swapped with turbo only and turbo and injector pump. I also have seen a BIG CAM engine swap and it was about twice as many mods to the engine mounting, oil filter location, cooling inlet, etc. I have no photos of the swaps, a local guy in my FFCMVPA did both. As a side note he said that a turbo swap did increased power but not as much as turbo and injector pump. I was told it was a night and day difference in power.

Vinny

 

[ColtRice17]

Ok, So my question here is, will any parts off of a 290 fir on the 250? or what will and what will not? if that is the case where should I look for the turbo exhaust manifold and pump? also how much PSI is really safe to run through a 250 like 10-12 psi?

 

[Motolodwick]

Hay Willwagner I have a 1988 NHC-250. I have been looking and looking for what turbo to put on this engine with no luck. I get most people put the Holset on but if no one says what model. If You could tell me part #s for such turbo I would be forever greatful. Thanks.

 

[ColtRice17]

Hb3t

 

[l3oss]

I noted the following from another nhc-250 TURBO thread:

Holset HT3B HT4B HX60

 

[l3oss]

... info might be useful to someone here ....Turbo---CFM----Racing HP-----Daily HP inducerHX35----574------420----------330------ 56TP38 767HX40----763------560----------440------60T66-----800-------560----------440-----66GTP38R 897B1------900-------630----------495H2E-----868------700----------550HX50----1000-----700-----------550-----63,67HX55----1050------735----------578-----67HT3B----1085------770----------605-----76GT42----1302----------------------------75T76-----1350------945----------743------76 HT60----1400------980----------770B2,s400-1500------1050---------825-----75GT47------------------------------------80HX60----1550------1085---------853TV81----1600----------------------------85T88-----1750-------1225--------963-----88HT4B----1800------1260---------990Big Brother-1900----1330--------1045-----87T91------2000------1400--------1100-----91HC5A/HX82-2450----1715--------1348T100------2600-----1820--------1430-----100T105-----2900------2030--------1595------105

 

[dmetalmiki]

Thanks for the info. guess that idea's trashed. how hard would it be just to swap the NHC 250 for a Big Cam Cummins? thanks again.

I would not junk the project yet,
I know a guy that put a turbo on a cummins in a wrecker, And when he turned up at a show, Wow!, Is all I can report for you.
Yes, There was 'Lump'' on the hood, (So what?)
Yes, He had to manufacture piping etc to complete the task,
He did not 'modify' or alter anything else.
But It sounded great. (It had a turbo that whistled just like a deuce).
He reported more power, No increase in smoke,and slightly better M.P.G.
He also stated firmly that he DID NOT (Ever) over rev the engine, And always drove in a careful and respectful manner.
I hope this helps you re consider changing your mind about 'Binning'the project.
Keep us posted. Good luck.
Just as an aside.
My boy fitted a "C" Turbo to my M45 530C fire truck, And did nothing else at all, And trust me, That truck IS the fastest truck in our fleet. Plus it Sounds absolutely awesome.

 

[Iceman3005]

You don't have to change the pump, the injection pumps are all the same. It's the fuel button inside the pump you need to change. I do believe most of the 250's came with a #38, change it to a #20 when you add the turbo. I did see somewhere that someone changed to a #20 without a turbo and it made a huge difference. Just need a pyrometer to monitor the EGT's.

 

[simp5782]

You have to also drill out the flow rate adjustment ball. And add a fuel pressure gauge to adjust correctly with your air flow. You also would need a 1100cfm air filter. If in overdrive if your egts climb faster than your RPMs then you are too hot.

 

[WillWagner]

Simp, SOME plugged/non AFC and most all PTG pumps are built with a shaft with no ball to drill out. I just pulled one from a V8-300 in the M123 and it had a solid shaft, it was returned with a solid shaft.

 

[simp5782]

Simp, SOME plugged/non AFC and most all PTG pumps are built with a shaft with no ball to drill out. I just pulled one from a V8-300 in the M123 and it had a solid shaft, it was returned with a solid shaft.

I'll send you every pump I come across to drill out. It sucks

 

[Iceman3005]

You have to also drill out the flow rate adjustment ball. And add a fuel pressure gauge to adjust correctly with your air flow. You also would need a 1100cfm air filter. If in overdrive if your egts climb faster than your RPMs then you are too hot.

Simp from what I have been researching, the ball is supposed to have a fuel screw on it that can be turned out. Is my research inaccurate? The forum I was reading said is was best to do it quarter turn at a time, so as not to blow up the engine.

 

[WillWagner]

Yes, they do suck if they are the hard azz Cummins part, but there is a plastic one that is used too, WAY easier! Yes, turn the screw out slightly, like 1/4 turn, it will do ALOT! The screw is under the ball, the ball is a "tamper proofing" so the fuel rate can't be messed with. Be careful when drilling, if the drill goes thru and grabs the slot in the screw, it will/can turn it all the way closed.

 

[simp5782]

Simp from what I have been researching, the ball is supposed to have a fuel screw on it that can be turned out. Is my research inaccurate? The forum I was reading said is was best to do it quarter turn at a time, so as not to blow up the engine.

Yes. Play with the adjustment conservatively. That's why its best to add a rail pressure gauge to see what you are doing.

Using a drill bit that is about a quarter inch to detent it. Then I go to a speed out but and drill into it and then use the extractor side to bust it loose. Much easier on a bench. In a 809 series truck is sucks hanging upside down. 939s are much more worker friendly