Turning up the fuel delivery rate does not affect idle speed, it will however make black smoke come out your exhaust when you step on the throttle until the turbo spools up. You can move the "star wheel" Turning it one way makes more smoke, the other direction causes less smoke. Many people apparently don't mess with the wheel at all and just let the engine smoke a bit on takeoff. To fix the smoke problem, you have to remove the smaller plug and turn the "star wheel" This effects how much diesel fuel is pumped into the cylinders before your turbo spools and boost pressure is created.
here is another good link that describes how to turn up the fuel delivery rate
Tightening your govenor springs will cause the rpm to increase. This mod is desirable because it also increases the engines max rpm. My engine is rated for 3100 rpm, but was governed @ 2,400. I turned it up to about 2,700. After you tighten your springs, you will have to back off the idle speed screw. This is the screw that is connected to the throttle linkage and is diffeent on just about every vehicle.
here's a good link for the gov springs....it's a tutorial on how to install new springs, but if you simply tighten your current springs about 2-3 clicks it'll increase your rpm's. The tutorial is for a cummins 5.9, but the same pump is on the DT series and the ford 6.6/7.8 litre.
while i'm at it, here is a link to a newer style 466/360/5.9 pump. Instead of installing the "new" fuel plate, you can grind down your old one...if you really wanna do this let me know and i can find more data for ya, even though i have not actually done this.