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GJF GJF is offline
Slantnose from HELL
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Join Date: Dec 2004
Posts: 809
You have 934 cams and they have alot of overlap. So I would suspect the vacuum at idle to be all most non-existant. So that would explain the no change in pressure when instantaneous throttle response. But with the vacuum line not connected it would not allow the fuel pressure to rise during boost conditions (bad). Does your boost gauge have a vacuum portion to read vacuum or if you look at your ECU during operation look at the current cell at idle and see what the ECU registers at idle, you can compare this to the amount of change your fuel pressure will see off idle. So if your car has 1" or 2" of vacuum at idle with the vacuum line connected the the pressure should drop the 1-2 psi But rise when you rev to "0" vacuum. I would remove the pump, replace the filter and get a "Mighty Vac" and connect it to the FPR and apply 5-10 psi to the regulator and your fuel pressure should rise as long as it is plumbed properly by the amount applied. If it doesn't change then the regulator is bad. If you want take the IC off and check the routing of the fuel line in and the regulators return to make sure they are plumbed correctly. If you are not sure take a picture and I can tell you if the plumbing is correct.
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, 09:24 PM
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