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GJF GJF is offline
Slantnose from HELL
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Join Date: Dec 2004
Posts: 809
Yes the rear pump is not needed on EFI cars. But a large single high volume, high pressure pump (like an 044) up front is. The two pumps used in series is one pump to make sure the other pump is feed a constant supply of fuel. The only reason on a EFI car to have multiple pumps is to have them in paralell with each other to make suer there is enough volume of fuel based on the amount of HP. I use Aeromotive pumps as well as Bosch. The Walbro 255 pumps are also a reliable pump.

Now the real question is...... although your fuel pressure is still 37psi..... When you drive the car, does the fuel pressure slightly raise during instantaneous revs, and start to increase under boost? Or does it still drop when brought up to 3500RPM? If it drops then it could be the rear pump and or a clogged fuel filter. Or it could also be the FPR but until the rear pump is removed and a new filter is installed the FPR is not a candidate yet.
87 911 Carrera platform
Twin Garrett's, Big Valve, Xtreme Cylinder Heads, JB Racing cylinders and machine work, custom JE pistons, GT2 EVO cams, GT3 oil pump, modified 3.2L intake, 80mm TB, custom Intercooler, equal length headers, DFI, KEP Stage 2 custom twin disc, G50 custom gear set, LSD, Tilton trans pump, Fluidyne cooler
Old 05-29-2008, 03:46 PM
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