I have twin 95 502 mag efi. I'm going from roughly 32 psi and after speeding up I slowly loose fuel pressure in 1 motor. I swapped both the vst and mechanical fuel pumps, replaced the fuel line to engine and the anti syphen valve. And it still does it. Not sure what to do next. And help would be appreciated! Thankyou

How much money and can you ship overnight?

I would first check your fuel line to make sure no debris blocks the line, pump, filters and so on, had that problem this spring...