Add to Favorite Sellers. 25-303BK AEM Adjustable Fuel Pressure Regulator. Acura/Honda – Inline Flange with 90 Degree Return Line Fitting; 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. Customer Service & Feedback. So we have a chance to make it right – we want your repeat business! Check out the official Holley Performance. For more great deals!!