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Part fits the following years1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973


    LeMans Main Caps 421/428/455 – angled Fits 1963-73 LeMans+ 5 other models

    Retail Price $355.95 You Save $32.96
    OPGI Price$322.99
    Part# G240066
    Mfg# 11500
    Low Stock
    Only a few left available for immediate delivery

    Increased block strength for 2-bolt and 4-bolt mains.

    These main caps, whether they be for 2-bolt to 4-bolt conversion, or you're replacing the factory straight 4-bolt caps with the Milodon straight, or angled 4-bolt caps, you're increasing the strength of the block. Because the angled main caps place the side loading to the outside of the block, the caps are located against the main cap register in the block preventing cap "walk". Milodon main caps have more cross-sectional strength due to the high-strength ductile material and yet they aren't so rigid that they transfer shock loads to the crank and bearings. The center three main cap kits come with all the bolts, washers and drill bushings needed. Block machining is required for final installation.

    • RETURNS: Discountinued part, no returns accepted.
    • These high-performance items are not eligible for any further discounts or promotional pricing.
    • High Performance, designed to improve performance.
    • Find in OPGI's 2018 LeMans Catalog page 439.
    California Prop 65 Icon WARNING: This product can expose you to chemicals including lead, sulfur, nickel, chromium, vanadium, titanium, polyvinyl chloride, and 4,4’-methylenebis (2-chloroaniline), which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.

    Vehicle Fitment

    Make & ModelYear RangeApplication Details
    Pontiac Bonneville1962-1976 421/428/455, Angled
    Pontiac Catalina1962-1976 421/428/455, Angled
    Pontiac Grand Prix1962-1976 421/428/455, Angled
    Pontiac GTO1963-1973 421/428/455 – Angled
    Pontiac LeMans1963-1973 421/428/455 – Angled
    Pontiac Tempest1963-1973 421/428/455 – Angled

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