AED 5580 Holley Vacuum Secondary Spring Kit

Vacuum secondary carburetors are designed for universal installation on varying engine sizes and power levels. In turn great improvements can be made by tailoring secondary opening rate to specific engine combinations. We have seen as much as 35 ft.-lbs. of torque increase on a 355 CID engine when combined with our machined throttle plates and hi-flow screws. We offer a complete spring kit and a kit that contains a sprint kit plus a quick change removable vacuum housing that facilitates thirty second spring changes.