COMP Cams Pro-Mag Hydr Lifters Chevy SB

Pro Magnum Hydraulic Flat Tappet Lifters. Specifically designed to perform at higher engine speeds. Proper position of internal piston at higher RPM prevents lifters from harmful "pumping up". Unique design yields significant power increase over standard hydraulic lifters. Adjustable valve train required. Pre-load .002"-.004" with engine warm. Applications: Chevrolet, Small Block V8 265-400, Big Block V8 396-454, Big Block V8 348-409 ('58-'65). Specifications: .842" Diameter - 99g Weight - 1.93" Seat Height. These Pro Magnum hydraulic lifters are designed to perform at high RPM without any harmful pumping up. These lifters for Chevrolet Small/Big Block and 348-409 yield significant power increase over standard hydraulic lifters.