Had a question on the proper way to set up a new adjustable fuel pressure regulator? Ok, after i install the regulator on the car and hook up my fuel pressure gauge/tester to the fuel rail's shrader valve. Then , I disconnect the vacume hose from the regulator right? Now what i need to know is this: I start the car and the desired pressure that i am looking for is at full throttle? say i want 50 psi fuel pressure, then do i floor my car while it is in park to full throttle? or do i set it at idle? please any help is appreciated.

 

You should be setting it at Idle. The vacuum line will allow the regulator to adjust accordingly with throttle application. As far as the proper pressure, it depends on your fuel injection system.
Standard TBI calls for right around 9-13 PSI
Standard TPI calls for right around 34-47 PSI

 

So what are you saying? to disconnect the vacum first right? and then start it up and adjust it at idle?

 

I'm not sure if you should adjust it with the vacuum line off of it or not. I would assume you adjust it with the vacuum line on. If for some reason you are getting a serious driveability issue after doing that, then attempt it without the vacuum line.

 

The FSM procedure for my 85 vette for checking fuel pressure is with the ignition switch on but the engine not running, looking for a pressure of 34 to 39 psi. The manual indicates that once you start the engine the engine vacuum will drop the fuel pressure 2 to 10 psi at idle.
Most of the info I have seen for AFPR's is to set the fuel pressure with the engine idling and the vacuum line disconnected.