any chance you have a r31 atmo computer, if so the pinouts for the vl turbo computer and the r31 atmo computer fuel pump are different, could have something to do with it, I think both vl computers are the same pinouts tho. Could try a different afm, possible that the computer has been re-tuned aswell, maybe try another, or that you are running atmo injectors and they are leaning out hard. The vl turbo had 270cc injectors as opposed to 200cc.