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GJF GJF is offline
Slantnose from HELL
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Join Date: Dec 2004
Posts: 809
Hey Dean,
Most injectors are rated at 43.5psi. With the vac/boost line disconnected you can set it to 42-45 psi. Once the vac/boost line is connected depending on vacuum your motor draws at idle it should pull the pressure down minus the vacuum. So let's say you are running 43 psi and you have 6" of vacuum then you should see 37psi at idle. And then once you romp on it the vacuum drops to "0" and then the fuel pressure will return to 43psi. Then from there for every psi of boost the fuel pressure will rise 1 psi for every psi above 0. So 43psi fuel pressure plus let's say 5 psi of boost you should have 48psi of fuel pressure, 10psi of boost you should see 53psi of fuel pressure.
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 08-15-2008, 03:26 PM
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