Sard fuel pumps

[GU11TY]

ok guys who is running a sard fuel pump
i was running a bosch 044 in my 2jz soarer before but it gave up the go and now installed the sard that used to be in my other soarer
now sard fuel pumps come with a new wiring loom that your supposed to rewire
but currently with the current car its just been plugged straight into the original fuel pump loom
ive done some more mods to my car but now anything over 15psi the car starts missfiring and stuttering
considering its got new spark plugs coils and leads im putting it down to fuel

now ive been told both things
that i do need to wire in a new fuel pump loom, and no that it should be fine
can anyone confirm this because my tuner told me that im running 55psi fuel and it should be running more and ive also been told 55psi is heeps

[George]

55 psi (over 3.5 bar) is adequate for stock engines. However this is only the case when measured before injectors rail AND under heavy load. If it drops under load then it's the pressure being the reason for misfiring. The pump itself (without fuel pressure regulator in the rail) should give about twice as much pressure.

Is there fuel pump ECU or 2-speed pump control with resistor installed? How did the trouble with misfiring began? Maybe you would search for bent fuel pipe or dirty filters? (that one in your fuel tank, too)

[thechuckster]

gu11ty: rail pressure should be around the 40psi mark (fuel pump on, engine not running/cranking)

At that boost pressure (15psi), the pump is pushing into a fuel rail regulated to 70psi which is fairly high. Surging & missing under load is more likely to be a lean condition if the spark is good.

[midnight_purple_GA70]

what was the sard pump that you put in? is it the same spec or better than the bosch 044?

get an afr gauge on it and see what its doing?

fuel filter as others have said is another good option...

the only reason i can see their pumps coming with a loom is that the current draw on them requires a larger gauge power wire or something...

[GU11TY]

yeh i think it needs a large current draw aswell
so if its not getting enough it wont be at its peak ey?

[George]

Sure. Check it out with voltmeter applied to pump terminals in different modes (idle, load) and compare to the voltage measured straight at the battery.