Hey fellas, Do these red Holly adjustable fuel regulators require the vacume line after setting the pressure?.I hooked Vacume line up to it and i can see it affects the pressure when I hit the throttle(pressure up). If I leave the vacume line OFF the pressure stays the same when hitting the throttle.

(1992 5.0 fox efi)

 

i think you want the pressure to spike when on the throttle.

 

leave vaccum line on.!!! that's the way it's suppose to work....under heavy or WOT fuel demands are greater..that's why the rise in pressure is needed

 

Thanks ,I just wasnt too sure since it has the adjustment screw on top. cool