NHC 250 Turbo Conversion in M923

[Bjmca]

Hi again guys, after many other projects around the place I finally got to work on my M923. I rounded up the parts to fit the turbo on the NHC-250 to get a little more from it. Before anyone starts screaming about blowing it up, have no worries, I have a big cam on standby . I will start with some pics and work from there. Here goes...........

 

[jwaller]

looks great except for the exhaust.
should make it last longer and run cooler.

It's a bit too redneck "hey I'm a big truck too" for me.

 

[Bjmca]

The exhaust manifold is a high flow from a big cam. The air/water aftercooler is from a BC2 I believe, I did not yet hook up cooling water to it, I really just liked the way it simplified air intake plumbing. After trails I will plumb water to it for cooling.

I do not consider a retrofit like this an easy task, and I know i've read elsewhere that its a weekend project, not on this truck.....

The heater box brackets had to be modified to move the box about 2 inches in the front for clearance. The coolant resorvoir will not fit anywhere else, believe me I tried . So plumbing for it had to be modified, brackets made, cursing etc.

The easiest part was hanging the exhaust manifold and turbo, and plumbing oil in and out.

 

[Bjmca]

Whats wrong with the exhaust?

The air inlet plumbing is temporary until the aluminum 51/2" tubing arrives and a couple new rubber elbows. The ones in place are freebees from a junkyard.

 

[Bjmca]

The guages are all up and working, just waiting for the other pod to mount the boost guage on the steering column next to the pyro.

When I got this truck the fuel was turned a full 8 turns out, the egts at that point with no turbo would run 1350 degs, and then I had to back out to keep from melting things.

With no other fuel mods yet, the truck pulls better and has cooled down to 980 degs and I can keep my foot right in at on a long hill.

 

[jwaller]

i guess I should have said the exhaust stacks.

 

[Bjmca]

i guess I should have said the exhaust stacks.

Maybe not for everyone, I respect your opinion, but they fit in very well here in redneckville

 

[quickfarms]

Interesting

 

[73m819]

i guess I should have said the exhaust stacks.

Maybe not for everyone, I respect your opinion, but they fit in very well here in redneckville

Your MONEY, your TRUCK, do what ever you want to do, as long as YOUR happy, that is what counts, no matter you do, it could be worst, it could be a bobber

 

[doghead]

You should see his daily driver...

 

[Bjmca]

Your MONEY, your TRUCK, do what ever you want to do, as long as YOUR happy, that is what counts, no matter you do, it could be worst, it could be a bobber

 

[Andydieselpower]

Looks great and thanks for sharing. The only thing wrong with stacks like those are if they have silincers or any kind of noise baffles, etc. A truck with a stance like that should have a nice turbo whine and a throaty idle exhaust note.


Good work! Post a video as I've love to hear it!

Andy

 

[Vintage iron]

Looks good. It is a lot easier in a 900 series!

 

[F'N!WreckerRay]

Looks great I just recently took my 816 and put a turbo kit on it. You can crank the fuel up and it will get you a lil more power as I did but it still was not enough! So I put small cam 350 injectors in her with a straight pipe with the flapper on the top to keep the rain out and she runs and sounds wonderful! I will be posting pics and video in the next day or so.

 

[Bjmca]

Just changed from the number 27 (stock) fuel button to a number 15. It pulls better and gets up and goes much better, egt's are running max of 1050 pre turbo on a long hard pull.

I am going to do a little shim work on the pump, then maybe a different button to see if I can squeeze a little more without spending major bucks on pump work or injectors. I will put the pressure gauge on it tomorrow to see where fuel pressure is at.

Should have the boost gauge mount on Wednesday.

 

[73m819]

Looks great I just recently took my 816 and put a turbo kit on it. You can crank the fuel up and it will get you a lil more power as I did but it still was not enough! So I put small cam 350 injectors in her with a straight pipe with the flapper on the top to keep the rain out and she runs and sounds wonderful! I will be posting pics and video in the next day or so.

On a non turbo, would the 350 injectors help, how much more egts, what was the cost for them.

]Just changed from the number 27 (stock) fuel button to a number 15.[/COLOR] It pulls better and gets up and goes much better, egt's are running max of 1050 pre turbo on a long hard pull.

I am going to do a little shim work on the pump, then maybe a different button to see if I can squeeze a little more without spending major bucks on pump work or injectors. I will put the pressure gauge on it tomorrow to see where fuel pressure is at.

Should have the boost gauge mount on Wednesday.

On a non turbo, what kind of egts do you think I would get by just changing the button from 27 to 15,

What is the thought on combining the button change and the 350 injector install on a non turbo 250, will things just be to hot for the engine, I do not mind blowing smoke, just do not want to be putting bits of motor out of the stack.

 

[Bjmca]

On a non turbo, what kind of egts do you think I would get by just changing the button from 27 to 15,

What is the thought on combining the button change and the 350 injector install on a non turbo 250, will things just be to hot for the engine, I do not mind blowing smoke, just do not want to be putting bits of motor out of the stack.[/QUOTE]

I don't think it could be done. My egts would creep over 1300 degrees on the motor on a hill with just the screw on the throttle shaft turned out 8 turns. Without any other changes and just putting some more air to it they came down a long ways. I think you would way over fuel the motor and not really make much more power.

Air+fuel=power. My truck is much nicer to drive now with the extra go, especially with the big tires. I am working on finding some shims to play with in the pump and then a little more fuel with a number 10 button.

I'm having fun thats all that really matters.

 

[Bjmca]

I would like to hear from a few guys that have done a similar turbo mod to a NHC250 with regards to injector, pump and other mods, and what buttons and pump settings they are running, with boost levels with EGT's

Anyone have any specs they care to share, I know i've read in the past forums about others with turbo conversions, there just does not seem to be any follow up on fuel settings being used.

Thanks in advance for any info you could share.

 

[jrobinson5093]

I like the way it looks. I bet it sounds good.

 

[Gunfreak25]

We would love video, I think the exhaust stack looks great, looks like it's factory done.