Holley #512-500-1 Fuel Pressure Regulator, Steel, Zinc Plated, Adjustable, 35-65 psi, Ford, Mustang, 5.0L, 1986-1993, Description: I have a new in the box Holley adjustable fuel pressure regulator part #512-500-1. I bought this for one of my old fox bodies and never used it. It is adjustable from 35-65psi. It is Zinc plated. This Holley fuel injection adjustable fuel pressure regulators allow you to adjust the amount of fuel pressure that is delivered to the fuel injectors. I will take $35 shipped or trade for parts for my 02 GT.