moog

iTrader: (14)

We can't really tell you if you'd run lean. You'd have to run it on the dyno. Or you could run it on the street with a wideband.

taurran

iTrader: (18)

You should only run lean if you're running a reflash. That's why theres such a small margin for error on turbonetics kits equipped with the reflash. Variations in the modification to the bucket assy will cause the car to run lean or rich if it's not drilled out to the precise specifications in the instructions because variations in fuel pressure cannot be fully adjusted for by the stock ECU.

However, if you're running a tunable EMS you should be able to compensate for this via tuning...

eez

iTrader: (1)

maybe your's is 80 because you have the walbro and FMU (with aux)

eez

iTrader: (1)

you can't run the FMU unless you also run the AUX pump. So, remove the FMU and Aux pump if you upgrade the in tank pump.

jpc350z

No, the FMU only allows flow to the Aux Fuel pump under boost..My 80 psi is the starting pressure and the pressure goes up from there when the FMU/Aux kicks in...At idle it's 80 psi...

ZU L8R

iTrader: (84)

Then you need to fix it, it should be @ 51 psi as Charles stated

jpc350z

Right, w/o the mod to the walbro the pressure will be at 80psi...I am going with a RFS shortly so it's pointless at this time to mod the walbro..

eez

iTrader: (1)

I understand that, but the FMU port is smaller than the hose, so maybe it's causing an increase in pressure because when not in boost the fuel is flowing through the FMU. Ever take one apart? I have.

phunk

iTrader: (21)

there is no fuel flowing the the FMU before the aux pump kicks on. Typically in most installation, there is, however, take a special look at the way in which its installed via the vortech directions on a returnless car.

eez

iTrader: (1)

how is that? please explain? If it doesn't go through the FMU, where does it go? LOL

Do you actually know how the FMU works???

Let me explain... Fuel flows through the FMU until boost is seen on the MAF. As boost pressure increases it causes this rubber bladder to close the valve and route fuel directly through the AUX pump, which at this time is turned on and pumping.

BTW unless the pump is on, no fuel can actually flow through it. I have studied this setup and dissected it because of the problems I have had.

so...prove me wrong.

oh here is a diagram for you

phunk

iTrader: (21)

sure, ill prove you wrong in the morning. cause your wrong.

jpc350z

Fuel does not flow thru the FMU until the Pressure line connected to it sees manifold pressure.(Believe a diaghram inside the FMU). Look at the install instructions and you'll see the line...Its Boost pressure sensed here that allows fuel to flow coupled with an electrical signal from the SS box to the Aux pump that allows a pressure increase of fuel to the rails..

I just noticed your schematic has a 5/32 vent hose that my set does not have...Interesting.. A difference between on 04 and 06 model's..

phunk

iTrader: (21)

rather than explain this, ill just point out that if the FMU was a restriction in your flow, as you suggest with your red arrows.... why would you see a spike in a fuel pressure?

eez

iTrader: (1)

when u put your thumb on a garden hose (not completely covering it) does it restrict the flow of water or increase the pressure?

phunk

iTrader: (21)

all the above?

phunk

iTrader: (21)

oh BTW, if the FMU was restricting flow, you would see a pressure drop, not a pressure spike, unless you are reading your fuel pressure at the wrong spot. A pressure spike would only be seen if there was restriction in a return side after a regulator. This is all if we are pretending that fuel were to flow thru the FMU during vacuum anyway.

eez

iTrader: (1)

i'm done debating with you...this is a useless waste of my time.

eez

iTrader: (1)

wrong

ZU L8R

iTrader: (84)

eez, do you realize you are arguing with someone that designs and makes fuel systems for a living?

moog

iTrader: (14)

oWneD!