1JZ fuel pressure drop issue!

macjac69

Supramania Contributor
Feb 5, 2007
274
0
0
Mississippi
My singled 1j fuel pressure drops when I turn the boost up above say 13.5lbs.
I've got a turbonetics T-60, 540 injectors, Walbro pump, aeromotive FPR, Stinger ECU. The stock lines are OK. The line from the tank goes to some apparatus on the side of the block just behind and below the oil filter is this a stock Toyota fuel dampner? Just what is it's function? And can it restrict flow?

My AFPR gauge drops from about 40psi down to less than 20 psi when under higher than 13.5lbs boost even when I adjust the regulator higher so my tuner set it at 13.5 lbs until I can get this issue worked out. I'm at 309HP and 295TQ I know I can make more power but not with this fuel problem. I was told there are different models of walbro pumps and I may not have the right one. I was also told to wire directly from the battery to the pumps because voltage may be an issue. Any help would be appreciated.