Product Summary

Many Engines, Hydraulic Flat Tappet Lifter Type

    Key Specs

    MFG. Part #858-1
    BrandCOMP Cams

    Need To Know

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    COMP Cams 858-1 Details

    COMP Cams Pro Magnum Hydraulic Lifter for Small and Big Block Chevy, Single Piece.

    COMP Cams Pro Magnum Hydraulic Lifters are specifically designed to perform at higher engine speeds. When engines are equipped with conventional Hydraulic lifters, high RPM is limited by improper positioning of the internal piston. Pro Magnum Lifters eliminate improper positioning and harmful pumping up. COMP Cams Pro Magnum Hydraulic Lifters offer a significant power increase over standard high performance Hydraulic lifters, especially in race applications where a Hydraulic lifter must be used. An adjustable valve train is required to use Pro Magnum Hydraulic 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


    1985-92 Cadillac 173-350
    1980-94 Buick 173-350
    1977-94 Oldsmobile 173-350
    1971-94 Pontiac 173-350
    1958-98 Chevy 173-454
    1960-98 GMC 173-454

    CARB Warning

    For race/ off road use only

    Emissions warning: this part only legal for sale or use in California for racing (competition) vehicles which may never be used, registered, or licensed for use upon a public highway. Any other use renders the vehicle tampered and not legal for use on California public highways (any public street or roadway, public dirt road, public park, or publicly maintained right of way open to the use of the public for vehicular travel). Violations subject to $37,500 penalty per violation per vehicle, revocation of registration, loss of use on California public right of ways, and proof of correction for tampering. There are similar restrictions and penalties under federal law and the laws of all other states with penalties under federal law of up to approximately $45,268 per tampered vehicle and/or engine.

    COMP Cams 858-1 Specifications

    MFG. Part #858-1
    BrandCOMP Cams
    Lifter TypeHydraulic Flat Tappet
    Link BarNone
    Lifter Link Bars IncludedNo
    Lifter Body Diameter0.842"
    Sold in QuantityEach
    GTIN Code036584930013