So i have a 4bt and it seems when i turn the full load screw in to almost runaway,it will run poor compared to when ive got it at the factory setting.Is there a point where the full load screw will overcome the AFC?It seems when its turned down it will add more fuel as boost rises.

 

probly needs some tuning or your pushing more fule than the lift pump can handle (starving)

 

Its hard for me to believe that a lift pump designed for a 6cylinder is running out of fuel.I do believe the lift pumps ar good to 250hp.Im at 180 at the wheels

 

wouldent surprise me

 

sounds like it is time for a air dog

 

You can have teh best lift pump in the world, If you plumbing sucks (like the stock plumbing) it wont help. You might have pressure but no volume.

 

Ive got 3/8 all the way back.no screen in the pickup.I did a road test and under the heaviest pull it drops to 4psi.This is smoking pretty good so i know its getting fuel.It performs better when its turned down.My smoke screw is raised from the stock position and it delivers "more" fuel.wtf