Includes both timed and full vacuum ports for ignition advance, Engineered to deliver smooth throttle response throughout the power band, Features a lightweight all-aluminum body is compatible with gasohol and blended fuels, Designed for 402 c.i.d. and larger engines with Edelbrock Performer manifolds and other brands of similar design, Uses metering rods to transition between circuits rods that can be changed in seconds without carburetor removal or draining fuel.