I just purchsed a BBK fuel pressure regulator for my truck and was wondering what the factory fuel pressure for a 1994 460 is so I have a baseline to start at. Also Is the pressure adjusted with the engine running or off but with the key on, I have heard both. Thanks

 

Probably around 40psi, It probably doesnt matter because you have to have the vacuum line off to adjust the pressure anyways.

 

Thanks, that is the pressure that I was thinking too. I will hopefully have time to put it on this weekend and do some testing. The truck is running a little lean due to the headers and I am hoping this will help.

 

I think that sock it is around 32lbs at an idle and around 38 to 40 with no vacuum. I would adjust it with the engine running. It will be more accurate because ifnot, the pump will not run continuous and you will not have the bleed of pressure of having the injectors opening creating a pressure drop.
I would start around 44lbs and see how that does.
Jimmy