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Hey guys,

I am installing my new adj. FPR and need to know what the fuel pressure should be when you just turn the key to the "on" position and not actually start the car?????...Does this reading even matter????...Should I even car about what this reading is, or only when the car is at idle, what about warmed up vs. cold, should the reading change???...Can I make adjustments only with the key on, b/c I don't want to put the intake and everything back on and realize there is a problem and have to take it all back off again...I already had to do that once due to a bad FPR I bought on ebay...I shouldn't have that problem this time as I bought a brand new Mallory FPR, but still don't you test everything with the intake off so if there is a problem you can adjust it on the spot, without everything in the way...I really need help with this so please let me know all you can...thanks,

Jason
 

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Problem with key on adjustments is you have no vacum being applied. It should be adjusted with the car running at normal operating temp
 

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not sure but......

could you not apply vacuum with a hand pump and do the same thing? Also I have a question. What kind of pressure does everyone get with just one cycling of the pump should it be 35 to 40psi or if lower say 12psi but 35 after engine cranks is 12 psi normal for 1 cycle of the pump???? :handball:
 

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I'm not sure, but I have a gauge, and I could check it tomorrow. I think the best way to set the regulator, is with the motor idling. Or, you can take the diagnostic plug, hold it so that the long side is on the bottom, and the short side is on top - it should resemble a house - four terminals along the bottom, and two up top. Take the bottom right terminal, and ground it. Turn the key to run, and the pump will run continuously. This is similar to idleing, but without the injectors bleeding off pressure. I'd start with 40 psi's, or maybe more with the supercharger. If you're apprehensive about using the EEC plug, you could probably jump the circuit via the fuel pump relay connector - in order to ensure pump operation with out the motor running.
 

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When I turn on my ignition my fuel pressure gauges shows 38 psi. I am using the stock FPR unit and that of course is with the vacuum line attached.
 
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