JAG33R

Hi there skyline mates, I just got one today Walbro GSS 341 for my Gtst R33 1998 model. Iam new here in SAU, if i could ask for your expert advice guys, I'm Not sure if I need to replace or change the stock Fuel regulator if I install this pump, it is necessary to dyno the car after pump is installed?? Will the car running safely if i keep the stock FPR unit after new pump is installed ??? Reason for this is just making that I dont cause any damage to the car. Some people to told to change Stock FPR to a SARD FPR item as this goes in hand with the pump replacement and must dyno the car afterwards. However, other SpeedShops also advised me that changing just the pump should be fine not necessary to change Stock FPR! No dramas at all if i have to change Stock FPR, I'm just wanting a confirmation on this point. I'am now kind of confused who to believe and any advice on this is much appreciated.