Mechanical Secondary-4150 By popular demand, Holley is expanding the draw-thru supercharger carburetor line to now include the XP series. Like the existing HP line, these are available in 600, 750, and 950 CFM flow rates and standard polished with black accents. The feature-laden XP includes a contoured venturi inlet for balanced air flow, screw in air bleeds for precision tuning capabilities, high flow billet metering blocks, billet base plate, and Dominator style fuel bowls which allow plumbing from either side.

Supercharger XP carburetors also have a unique capability that allows their power valves to reference the intake manifold vacuum below the supercharger. This allows the power valve to operate as it should, based off intake manifold vacuum. A power valve provides further enrichment to the main metering system under load (low vacuum) conditions.

Holley XP carburetors are the standard for square bore race carburetors. Race-Ready out of the box! This model of carburetor has the square bore flange bolt pattern. It can replace Holley, Edelbrock, Carter AFB, and Autolite style carburetors with 5 3/16" x 5 5/8" bolt pattern. If you have a spreadbore style intake manifold, you will need an adapter to install this carburetor. Similar to the Mr. Gasket #1932.