FASS Adjustable Fuel Pressure Regulator Universal Gas / Diesel FPR-1001. BRAND NEW IN BOX. FASS FUEL SYSTEMS ADJUSTABLE FUEL PRESSURE REGULATOR (FPR-1001). The FASS Fuel Systems Adjustable Fuel Pressure Regulator is intended for aftermarket performance applications requiring higher fuel pressures than a typical daily driver. These applications can vary from drag race vehicles, competition pulling […]