What you really want to do is put a 4500 rpm spring in it, no actually you probly dont, unless your fine with scatterin your motor eveywere, which i am still yet to do, btw did you see my high rpm run video?

 

Internal is max pressure.
External is fuel curve.

And again, a pyrometer is a very good idea before you adjust either.
Melted pistons are a reality, expensive reality.

 

so what would adjusting the fuel curve do exactly?

 

Like when you take off right now, at say 25% throttle you have no smoke.
Adjust that screw out, same 25% throttle and the smoke rolls black.

You adjusted the fueling curve to throw more fuel to the engine at lower RPM.

To much smoke at low RPM, turn the screw in, smoke at low RPM decreases.

With a little experimentation, you can get a light haze of black across most of the RPM range by balancing the internal and external screws on a turbo engine.

Takes lots of little adjustments to get it just right.

 

so do the pumps on the 94's have 3 adjustments or 2? i know the one on the triangular cover is there and the external nut at the back of the pump is there but what about the one i am remembering inside of the fuel line on the center of pump?

 

Unless you have an IP test bench, leave the one inside the fuel inlet alone.

It don't change how much pressure or fuel the IP puts out.
All that changes is the internal IP pressure, which changes the timing and timing advance.

On a test bench is the only place you can get that one right.

 

Leave the low rpm screw alone too. I've spent countless hrs experimenting with the so called torque screw. Trying to get My turbo to spool at lower RPM's.

It's not a torque screw. It's a low RPM fuel limit.

The only thing it effects is the amount of low rpm emissions You produce. ie: smoke. We don't need any more enviro ****'s coming for out older trucks.

 

I just finished messing with that screw. I gained to 2 psi max boost and it felt like i had a little more throttle response. I went about 1.5 turns out. But i didnt notice any more smoke. Ill have to check egts on the highway. Can only go 45 or so on my road.

 

For best results, you have to adjust both the internal and external screw to get the best balance.

I have found a lower internal setting and turning the external screw out can give a bit more power down low and still keep the smoke down.

If you have the internal screw turned in several flats, then turn the external screw out a couple turns, power goes down and smoke increases to the extreme.

Small adjustments to both screws, drive it.
Small adjustments to both screws, drive it.

It takes time to figure out where both need to be set for the best results.

IP condition, injector condition, your elevation, turbo condition/boost level and the condition of your engine make this a different setting for every motor.

Stanadyne has two settings, regular and high altitude.
Most of us do not live where either those settings would be optimal.

 

Part of me regrets not trying to mess with that screw, but in reality I just don't have the time anymore. I've sent my pump off to be rebuilt now that I don't need my truck for a couple months. Supposedly it should be a fire breather if what they say about this thing is true. Should be good for a couple giggles.

Can't wait to fire it up when I get home. I think I'm going through withdrawl after being away from that clatter for so long.

 

Did you decide to get moosed? My only problem with it is it only turns just barley 3000rpm i just couldnt live with that

 

Brave words for a guy that likes to bump past 4000 RPM on a stock 6.9

But yes, thats what I decided on. I can get 10+ PSI smoke free by 2500 RPM and hardly ever go to 3000 RPM. Considering my tall gearing I simply don't need higher than 3000 anyway. I might have some slight tweaking to do on the transmission computer for the lower governed speed.

Honestly it was the more thorough rebuilding that sold me on them. What I learned about rebuilt pumps is that they are a lot like rebuilt engines. Doing it right takes a lot more than doing it well enough that it will run. Tighter pumps have more steady fuel/timing curves, and that means better MPGs. From what I read, the hot pumps tend to get good economy when cruising and thats what I'm after. If I could, I would have rebuilt it myself, but I can't. At least not yet, so this time around I will fork out the money.

Locally I could have spent about the same for a bone stock remaned pump so it was a no brainer. Nice guy here in town, but he doesn't like the idea of custom work so I gave up going to him.

Guess I could have gone for a "baby moose", but c'mon, would you settle for that on a studded turbo IDI?

Even if it gets a mere 0.5 MPG better then it will pay off fairly quick even with the higher price.

 

well you may finally get to hit 20 psi