Holley HP™ carburetors have been the standard in racing carburetors for nearly two decades. Powering the biggest names in NASCAR to the Saturday night racer, HP carburetors are the perfect choice for all types of motorsports. HOLLEY, HOLLEY,Supercharger HP carburetors are available in 600, 750 and 950 CFM and feature a contoured venturii inlet for balanced air flow, screw in air bleeds for precision tuning capabilities, high flow metering blocks and Dominator style fuel bowls which allow pluming from either side for ease of installation. HOLLEY, HOLLEY,Supercharger HP 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, HOLLEY,Holley HP carburetors are the standard for square bore race carburetors. Race-Ready out of the box!