its funny, my nnbs truck has a variable speed/volume pump and you can control the pressure and volume through the tune. I have an electronic fuel pressure gauge and when I go WOT with the turbo my pressure goes from a steady 54 psi reading on the gauge to 59 psi even though I thought I had the tune locked to a steady pressure of 58 psi. You need to find out if you have the variable speed fuel pump controller on your truck before doing the walbro or you may be better off running a whole new power supply from the alternator to the fuel pump with a relay like racetronix or casperelectronics sell, the hotwire kit.