Sweetser54

vortec350ss im running pump gas. at 9psi with 60 lb injectors im at 73 % duty cycle. i dont think the factory wiring going to the 340 lph pump will work past that bc of voltage drop. what im asking is if i do the 10 guage hot wire kit to the pump if that would be enough or will i have to run a return line to the tank and mount a boost referance regulator to the fuel rail.

Atomic

iTrader: (42)

Sounds like you need a bigger fuel pump or yours is dying.

Sweetser54

Atomic. 340 LPh should be plenty of pump with 60 lb injectors I would think to get 12 lbs of boost or 550 rwhp. That's what leads me to believe the stock wiring is not enough to feed that pump the volts it needs?

Ferocity02

iTrader: (59)

Definitely up the wiring to the pump first before calling it a bad pump.

I asked before, are you logging fuel pressure? Do you know for sure that it's dropping?

03sierraslt

iTrader: (22)

That pump and injectors should support that no problem, I would upgrade your wiring as the stock wiring will not support a decent amp draw.

AKlowriderZ71

iTrader: (22)

Is your '03 returnless? Has the fuel system ever worked properly, or is this a new install? A little more info would help narrow down your problem.

Sweetser54

I don't think the tuner is logging fuel pressure. He just claimed he knew it was dropping on anything past 9 lbs of boost.

Sweetser54

Yes it's returnless. It is NOT a new build. I just recently tried to turn the boost up to go to the track and I ran into this on the dyno. So he set it back to 9 psi and it works great there at 73% duty cycle.

AKlowriderZ71

iTrader: (22)

I'd try a Hotwire kit first. If you still have an issue, then I'd check for a burst or kinked fuel line in the tank. If that all checks out okay then I'd convert to a return style system. IMHO, return style with a vacuum/boost 1:1 regulator is the best for any boosted setup past 7-8 psi.

Atomic

iTrader: (42)

Why do you think so?