i am having a problem when i reach 5k my fuel pressure drops immediately to 31. this is about 8lbs. i have a brand new walbro. i am wondering if the pump does not have enough volume. these are my mods

13b-re street ported
1600s'
mallory reg
60-1
sfp manifold
walbro
9lbs flywheel
bonez race clutch
e6k