Fuel Pressure Regulator

[Hossbaby50]

What specs are within range on a FPR? I checked mine again today to try and diagnose my poor running issues. I checked it both with and without the vacuum line connected. MAF TPI w/walbro inline pump.

w/o = 46PSI constant idle & rev.
w = 38psi constant idle, 45psi under accel, 34 psi under decel.

Harley

 

[4X4HIGH]

What engine size are we dealing with?

Back when i did a TPI conversion on a 350 45psi with vacuum hooked up and it should raise 8-10psi with the vacuum line disconnected.

 

[Hossbaby50]

350.