NTC 400 Mo Power - Steel Soldiers::Military Vehicles Supersite

eldgenb · 01-13-2011, 20:10

Well, I may very well the first person in the world to actually post a picture of where these items are and how to do it, I could find plenty of half baked descriptions but no pics anywhere so this was a praying moment for me. I talked to Ross REB87 Who saved me from drilling the item that I thought was right and led me to doing more research before I did anything. What this thread is about it how to drill and adjust the fuel screw on the NTC 400 found in the m915 series trucks. "I am in no way wanting you to do what I did due to the fact that it alters your emissions for your truck and after this procedure and following procedures I returned all items to stock to remain compliant" Ok now that's over with lets get started. You will need a sharp punch, hammer 1/4 and 1/8 drill bit, a long screw roughly close to the 1/8 size drill bit and a very skinny screw driver. I also plan on shimming the gov. and adjusting the fuel aneroid to get the most safe power out of these rigs. If you adjust these you take everything into your own hands I will not be held liable for any changes you make.

Firs off you have to find the tamper safe brass ball on the end of the throttle shaft NOT THE LEVER. It is in the end of the actual shaft. You need to center punch it and use the 1/4 drill bit first. You will drill about 1/4 inch out of the ball that is in there and stop. You will then use the 1/8 drill bit to drill the rest of the way through. Then you will use the screw and try to thread it into the 1/8th hole and pull on it to remove the remaining pieces of the ball which will expose the screw inside the shaft. To increase the fuel you will turn it counterclockwise until you reach the desired power, word on the street is 6 full turns. and thats it. I noticed it drove kinda like my truck but a lot angrier and with almost no lag for spool up. I will keep you posted on the other mods over the next few days.

eldgenb · 01-13-2011, 20:18

by the way since I know it will come up many will want to know what this actually does. Well the fuel that enters the pump first passes through the throttle shaft. The screw that you adjust limits the amount of fuel that can be sent to the injectors, when you open that choke point up it allow the engine to fuel much more, I will see how it goes when I get deeper into mods and I will try to come up with a gauge that monitors my fuel pressure, 225 psi is about as high as you want to go. I will do the dual fuel line mod which you basically remove a plug on the front of the engine, t-off the fuel line out of the pump and run fuel from both side of the engine, this keeps the forward cylinders from succumbing to low fuel pressure because all of the rear cylinders depleted it. The main reason for me is 20-25 hp gain and a much more responsive throttle.

Oh and Soni, please link this into the 915-920 tech and tips when you start the new one.
Thanks.

86m1028 · 01-13-2011, 21:22

Thanks for the info

Please keep us posted on the outcome.

Bighurt · 01-13-2011, 21:30

Quote:

Originally Posted by eldgenb

by the way since I know it will come up many will want to know what this actually does. Well the fuel that enters the pump first passes through the throttle shaft. The screw that you adjust limits the amount of fuel that can be sent to the injectors, when you open that choke point up it allow the engine to fuel much more, I will see how it goes when I get deeper into mods and I will try to come up with a gauge that monitors my fuel pressure, 225 psi is about as high as you want to go. I will do the dual fuel line mod which you basically remove a plug on the front of the engine, t-off the fuel line out of the pump and run fuel from both side of the engine, this keeps the forward cylinders from succumbing to low fuel pressure because all of the rear cylinders depleted it. The main reason for me is 20-25 hp gain and a much more responsive throttle.

Oh and Soni, please link this into the 915-920 tech and tips when you start the new one.
Thanks.

Have you messed with your fuel button's?

Only reason I ask and this is a big deal when you start messing' with diesels fuel. When you begin to increase the fuel beyond the factory settings your EGT's increase, this can be bad. I'm not saying not to do it, most of these trucks are emissions exempt anyways.

It should be recommended to anyone swapping out buttons and messing with the the throttle screw that you should have a pyrometer installed to watch your EGT temps. There is a reason why Cummins installed the tamper-proof ball......

I wish I could just win an auction so that I can play too...

eldgenb · 01-13-2011, 22:22

Quote:

Originally Posted by Bighurt

Have you messed with your fuel button's?

Only reason I ask and this is a big deal when you start messing' with diesels fuel. When you begin to increase the fuel beyond the factory settings your EGT's increase, this can be bad. I'm not saying not to do it, most of these trucks are emissions exempt anyways.

It should be recommended to anyone swapping out buttons and messing with the the throttle screw that you should have a pyrometer installed to watch your EGT temps. There is a reason why Cummins installed the tamper-proof ball......

I wish I could just win an auction so that I can play too...

No I have not done any buttons, I do not plan to. This is in place of the button, I visited with a cummins pump guy here locally and he said that he would recommend adding fuel before adding pressure, he also gave me a bunch of shims and told me 30rpm per shim. I truly believe that these trucks are easily and safely capable of another 50-75 hp without any concerns, I do not plan on doing everything to the truck, just select what is cheapest or in this case free and best for my use. The gov. shimming will just raise the rpm in which the pump defuels and the aneroid just dictates when the trucks begins to fuel, at least how soon pre boost. The fuel screw is the only power adder beside the dual fuel lines I intend to do.
I agree if you do more than one adjustment power wise you need an egt gauge, matter of fact I think everyone should have one anyways, cheap insurance.

WillWagner · 01-13-2011, 22:51

6 full turns will give WAY more than 20-25 HP!!! 1/4 turn out will give 20 or so HP at rated RPM. In to decrease, out to increase.

eldgenb · 01-13-2011, 23:02

Quote:

Originally Posted by WillWagner

6 full turns will give WAY more than 20-25 HP!!! 1/4 turn out will give 20 or so HP at rated RPM. In to decrease, out to increase.

oh yeah I figured that, 6 turns is the max I will go. I am thinking around 75hp, the 20 ish comes from the dual fuel lines, just makes sure every cylinder gets its fair share is all.

Bighurt · 01-13-2011, 23:04

Quote:

Originally Posted by eldgenb

o dual fuel lines, just makes sure every cylinder gets its fair share is all.

I assume your running the second line to the #1 cylinder port?

This mod was discussed on TDG some time ago, wise mod if you ask me.

Jeremy

eldgenb · 01-13-2011, 23:28

Quote:

Originally Posted by Bighurt

I assume your running the second line to the #1 cylinder port?

This mod was discussed on TDG some time ago, wise mod if you ask me.

Jeremy

yes to the #1, the theory is that by the time the fuel reaches the #1 cylinder since it starts from #6 the pressures is pretty low, by doing the mod you only gain horse power that should have been there to start with and I think it decreases the chance of a lean burn.

WillWagner · 01-14-2011, 00:27

Diesels don't have rich and lean burns. Gasoline and gasseous fueled engines do.