fuel pressure question

[doggiedave]

Good afternoon, I know everybody is tired of fuel pressure quetions. I'm trying to finish tuning my 383 motor. I have a fuel pressure guage mounted to the fuel rail in the shrader valve port(oil dampened) the needle on the guage bounces like crazy between 30psi and 50ps at a steady pace with vacuum line off or on and somewhat steadies up when increasing engine speed it seems to all but impossible to set pressure. any ideas? pulsator or pump issue? thanks

 

[vetteboy86]

I actually had the same problem after my 383 was done. I went to buy a new gauge and that problem went away.I am not sure if it was the way the needle in the valve was, or if the gauge was screwed up. The old gauge did however work fine on my brothers car.