2G Not enough fuel pressure under boost,

[Brad Bell]

Have a 420a turbo system, BEGi fuel pressure rising rate regulator installed, Walbro 255LPH GSS432. Under boost, or even when I really step on the gas, the engine stutters and coughs, like a strong misfire. Under the 8psi I am running, i should be running around 80-85psi fuel pressure, I am only getting around 60psi. Is this the case of a bad fuel pump? The regulator does work, the pressure goes up and down with the throttle. But the pressure just doesn't go high enough. Basically, whenever I step on the gas hard, or floor it in any high gear, the engine will jump and stutter hard. Could possibly be spark plugs as well because I haven't replaced those in a while.
Please someone help!
Thanks
Brad

 

[scarlett]

There could be a number of things that are wrong. Fuel pump, regulator, injectors, fuel filter... etc if it doesn't shut off at idle or average driving then you have a fuel restriction. Pull the spark plugs and check to see what they look like. Good plugs should be golden brown. If not they could be bad

 

[Brad Bell]

There could be a number of things that are wrong. Fuel pump, regulator, injectors, fuel filter... etc if it doesn't shut off at idle or average driving then you have a fuel restriction. Pull the spark plugs and check to see what they look like. Good plugs should be golden brown. If not they could be bad

Is there a way to test or know how much psi my pump is putting out at idle? I replaced all the lines including fuel filter, so I know there is no restriction. It just misfires under load at low rpm, that is really the problem i'm having here.