For returnless fuel systems. The new Aeromotive Billet Digital FMU is a fully adjustable, scalable electronic FMU designed specifically for returnless fuel systems. The Aeromotive FMU senses manifold pressure and automatically provides the fuel pressure that you dial in, maintaining proper air fuel levels at all operating conditions. When used in conjunction with an external fuel pump, the Aeromotive Billet Digital FMU will allow a supplemental pump (sold separately) to provide the proper volume thereby increasing the system pressure. The Digital FMU is scalable and completely adjustable to provide increased fuel pressure levels at any boost. The unique capability of the digital FMU, unlike traditional FMUs, is the ability to provide “any” fuel curve throughout the power range. The FMU features LEDs that are tied to a scalable rotary knob. This allows you to create a fuel pressure curve that corresponds to your boost curve. The housing of the controller is made out of Billet 6061-T651 aircraft aluminum alloy and is finished with a bright dip red anodize.