Low rpm shutter/stumble?

I have noticed a low rpm shutter or stumble on my truck. I didn't really notice it untill I put in a set of 5x14 (New Era 435) injectors and holly cow it brought it out. At that time I had stock Gov springs and thought it might either be the stock gov springs or maybe my 181 DV's were too small for the injectors. I have taken the injectors out and since done a 4K GSK and can still pick up on the stumble.

It's a light shutter between 1200 and 1500rpm's under light throttle. Heavy throttle or higher rpm makes it go away. I plane on double checking my gov springs and make sure they are not off one click or each other. What else might cause this other than the pump being out of balance? It only have 134K miles and has not been off the truck yet.

Any ideas?

not to hijack or anything but, i put some ddp2 in my truck, 160hp pump all stock. and i get the studder at around 1000-1100 rpm with very light throttle, was far worse until i bumped the timing from 13.5 - 16.5. ddp said my DV's were to small being a 160

That's governor caused in my experience. The more fuel you have the worse it is in my experience. I think some pumps ballance out and some don't atleast by back yard methods (non bench). Good luck and let me know how you fix it if you do. I tried about 8 different governor click setups this week to fine tune mine and had no luck getting the smothness to show it's face!

I had the same prob and my timing had slipped. Advanced and solved the prob. But I m not sure about your case since it didnt start till the inj's.

mine was really rough untill i bumbed the timing, now its only as bad as it was before the injectors, i adjusted the afc a few turns foreward and got rid of most of it.