So I installed a greddy manifold and fuel rail on my RB25DET Neo and I’m having trouble setting the correct fuel pressure (43psi without vacuum). Every time I try set it the needle on the gauge flutters like mad. I can set the fuel pressure just below 40psi and the needle stays still. As soon as I go 40 or above it flutters. I had a cheep Fuel Pressure Regulator on at the start and maybe thought that was it. So I put a malpassi/sytec FPR and gauge and still flutters. I also put a new fuel pump on(Walbro 450/455). I put a new fuel filter in and the flutter lessened but it’s still there. I am running an6 lines. I’m thinking maybe a leak somewhere but I can’t see any fuel.