AEM FPR Adjustable Fuel Pressure Regulator For Acura Honda B18 D15 D16 25-300BK. AEM’s Honda/Acura Adjustable Fuel Pressure Regulators are capable of supporting enough fuel flow for engines up to 1000 horsepower. Our patented interchangeable discharge ports enable the regulator’s output to match the output of any fuel pump. A single large discharge orifice is included. AEM includes a custom barb fitting to accommodate the factory fuel hose and the base of each regulator is tapped to accept a -6 AN or 9/16×18 fittings.