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Discussion Starter #1
im looking to get a pressure box next, will it every power say when pulling a load or just crusing, or will it only help on wot?

and whats the next recommendation? would 90's nozzles be to much or turbo first?
 

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Pressure box will help throughout the rpm range. Especially combined with the Smarty. Keep in mind that running higher rail pressure is not always good for the components, and injectors on these trucks are $$$. If you can, get a pressure box that has an off setting, or very low setting so that you aren't constantly having extra pressure. Make sure it is also a box that can quickly be turned up when you want to play.

TS Mp-8 is a favorite of many, or the Dr.P boxes (I have never used one), and the old standby Edge EZ (but it has no OFF setting just low)

You will need a rail gauge of some sort the keep an eye on the pressure, at least I would want one. Also helps you tune other variables on your rig.

As far as injectors, BBRAM is right, 90hp stix are nice for power. But they do get toasty, and you will wanna be ready to order up a decent turbo at the time as well. I don't think the CP3 on your truck will flow enough the keep up with the Smarty, a pressure box, and the 90hp stix. I suppose you could get a turbo off an 04.5+ truck and use that until you get something else, that seems to be affordable.

You can probably get away with doing an Arson kit or Bag of Parts to the Cp3 though. You've got the low side fuel covered with the Airdog.

What pressure is your airdog set at right now?
 

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A pressure box will compliment the Smarty very well. A set of 90's will also help things out, but a turbo upgrade will be needed to keep things cool, unless you can control your right foot. lol
ya, x2^ be carefull with pressure on stock injectors.
 

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Discussion Starter #5
i was planning for the mp-8. so it does have an off setting?
i already have a rail pressure gauge, so what am i looking for so i can avoid injector damage?

i unhooked my fuel pressure gauge when i installed my airdog because i had it on the bottom of my fuel canister. my fitting just came in today so ill hook it up tommorow.

i have my moment with my right foot getting heavy, but try to stay light on it.

i have a 38 foot toy hauler, we pull to the gncc. so i need to do the sticks and turbo at the same time, or i will be getting things way to hot?
 

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MP-8 Has a dial type control for it, and there is an OFF position.

You have an earlier model truck, that runs a little lower rail pressure. The 04.5+ trucks are quite a bit higher when cruising. Stock mine would sit around 19-20k just cruising down the freeway at 70mph. Around town somewhat less. But when I would turn the pressure box on, it would go up by about 1000-1500 on the EZ level 2, and level 3 was like 2500-3000 psi higher. That would put me at 22-24k cruising down the freeway.

It cracks the bodies of the injectors when you do it too long, and eats up and can crack the nozzles as well.

I try not to use any extra pressure at all when I am at cruise. WOT is Okay, I just don't want to cruise for 3 hours on the freeway at 22k psi.

I wish I could do that for days on end, the mileage really goes up when you jack the pressure up like that. It also makes the truck more peppy.

I guess after having injectors upgraded on 2 different trucks at a significant cost, I just don't want to stress them when I don't have to.
 

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Discussion Starter #8
thanks for the info. ill be getting one soon hopefully, now just to find the best deal.
 

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I have the MP-8, I don't care for it. I prefer the Edge EZ much better.

The 4.2 is pretty strong, if you leave it turned down, you may be fine with the sticks. But the added air when adding fuel, is always a good thing.
What don't you like about the MP-8? I have ordered my rail pressure gauge but dont have it yet... Still trying to learn about what pressure range is safe yet still good for increasing mpg's.
 

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MP-8 Has a dial type control for it, and there is an OFF position.

You have an earlier model truck, that runs a little lower rail pressure. The 04.5+ trucks are quite a bit higher when cruising. Stock mine would sit around 19-20k just cruising down the freeway at 70mph. Around town somewhat less. But when I would turn the pressure box on, it would go up by about 1000-1500 on the EZ level 2, and level 3 was like 2500-3000 psi higher. That would put me at 22-24k cruising down the freeway.

It cracks the bodies of the injectors when you do it too long, and eats up and can crack the nozzles as well.

I try not to use any extra pressure at all when I am at cruise. WOT is Okay, I just don't want to cruise for 3 hours on the freeway at 22k psi.

I wish I could do that for days on end, the mileage really goes up when you jack the pressure up like that. It also makes the truck more peppy.

I guess after having injectors upgraded on 2 different trucks at a significant cost, I just don't want to stress them when I don't have to.
I do not think the mp-8 goes totally off.
 

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What don't you like about the MP-8? I have ordered my rail pressure gauge but dont have it yet... Still trying to learn about what pressure range is safe yet still good for increasing mpg's.
That is the problem. To increase your mileage you have to run the pressure up, but to make a guess as to what is safe is would be tough. Some guys seems to run there mp-8 at 75-100% all the time and don't have issues! Then theres me, I ran my EdgeEZ for the first 20k miles on lvl 2 and had a couple of injectors that were very marginal, and one cracked body. Replaced at 20k miles with a set of F1 Flux 2's, and stopped using additional pressure. I now have 65k on the truck and no issues whatsoever with the injectors.
 

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The MP-8 has no consistency, it would be better if the adjustment ratcheted or something.
And after a WOT run, it piles up my rail pressure gauge readings.
I hear that about the adjustment style. Especially since I have the nob mounted where I can't see it.

I don't understand your last sentence though, the one I made blue. What do you mean it piles up your rail pressure gauge reading? What gauge do you have and is it logging certain peak pressures or something?
 

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That is the problem. To increase your mileage you have to run the pressure up, but to make a guess as to what is safe is would be tough. Some guys seems to run there mp-8 at 75-100% all the time and don't have issues! Then theres me, I ran my EdgeEZ for the first 20k miles on lvl 2 and had a couple of injectors that were very marginal, and one cracked body. Replaced at 20k miles with a set of F1 Flux 2's, and stopped using additional pressure. I now have 65k on the truck and no issues whatsoever with the injectors.
Sounds like we share the same luck.........

I have my mp-8 all the way down most of the time. If I drive with it on I go no higher than half, except for a short burst to race of blow a puff out the stack. Then it goes to 100 for a very short time. So far so good but I've only had it for a short time.
 

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I do not think the mp-8 goes totally off.
Is there a model that is newer than the one I had from back in like 2006? That one had a rotary knob, with an effective off position (0) and on up to 100.

Maybe it has changed since then? That was what I liked about it.

It was a little flakey with the boost fooling though.
 

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I believe it is the same. . . did the knob make a linier sence on your r/p gauge?
 

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Ok you are giving me good info here BBRam but now I have to ask what is normal it idle? Not 3000 I take it?
 

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The injectors won't even fire with 3k. I think they need 6k to fire the injectors (at least on the 04.5's)

And my MP-8 knob was NOT totally Linear. It was kind of weird.
 
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