Spec 3
These are custom built to a track and dyno proven design. They feature fully adjustable billet metering blocks, billet aluminum base plate, stainless or plated hardware, and an HP body with a special venturi/booster/base plate combination. These are super smooth, responsive, and make the power you’re looking for. These work great on IMCA and UMP modifieds and late models with 358-421 C.I. motors.