slimer

iTrader: (13)

so what is the exact setup to use the walbro fuel pump (3.33 pulley)

i have the aem fpr and the fuel rail fitting from sx7r and its going in tomorrow nite.

what happens to the fmu?

i just want to know exactly what goes in.

Steve

Stephen Max

iTrader: (59)

The fmu receives fuel from the fpr and sends it to the fuel tank, so the order of components is:

fuel pump => filter => fuel rail => fpr => fmu => fuel tank

slimer

iTrader: (13)

thanks, thats the type of thing that i wanted to know.

what baseline presssure should i set it at with stock injectors w/ seeing 10 psi of boost?

Stephen Max

iTrader: (59)

Set it to oem base fuel pressure, i.e. 34 psi. With the oem fpr, the Walbro (if it is the high pressure pump) gives you about 40 psi.

slimer

iTrader: (13)

and the fmu will raise fp based on bp?

Stephen Max

iTrader: (59)

Yes, the fpr will raise the fuel pressure at a 1:1 rate with increasing manifold pressure until the fmu takes over when the manifold pressure reaches a sufficiently positive value. Then the fuel pressure will rise at a rate determined by the fmu.

matty

iTrader: (54)

so for a s/c you need to run a line back into the fuel tank after the FMU ?? Im kind of new at this..

Walbro then filter then to fuel rail then fpr then fmu...???

slimer

iTrader: (13)

its in the directions for stillen for the fuel return

its stock on our cars

Stephen Max

iTrader: (59)

The 4th gen already has a return line, so you don't have to add one, if that's what you're thinking. Just hook up the return line to the exit port of your fmu.

The return line is the fuel hose coming out of the firewall that doesn't have the fuel filter attached to it.

slimer

iTrader: (13)

BUMP

does ANYONE have some specific directions for the installation of the fpr?

Stephen Max

iTrader: (59)

1. Remove the oem fpr. I found it much easier to get at the lower screw after unbolting the throttle body and moving it out of the way. Apparently the screws are Loctited in, so use the proper size Phillips head screw driver and don't let it slip out and damage the screw head. If you do strip the screw head, use a screw extractor to remove it.

2. There is a short fuel line from the oem fpr that runs to the metal fuel and vacuum hose manifold thingy under the throttle body. The fuel line is an extremely tight fit on the fpr. I just cut the hose off off.

3. Install the aftermarket fitting into the fuel rail with a new o-ring. I suppose you could re-use the o-ring from the oem fpr, but that is not a good habit to get into.

4. Run a fuel line from the fuel rail fitting to your aftermarket fpr.

5. Run a fuel line from your aftermarket fpr to the fuel return line going to the tank. To do this, you will have to disconnect the return line from the manifold thingy I mentioned earlier. Or just cut it off. You will need a brass 5/16" hose splice that you can get from a hardware store. If you can't find a 5/16" splice, a 3/8" splice will work. I found that the local Ace hardware has a much better selection of brass hardware than Home Depot, if that helps. Splice the return line to the line coming from the fpr.