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Part fits the following years: 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971

Tempest Main Caps 421/428/455 – Angled, by MILODON

Part# G240066

Mfg# 11500

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SAVE: $32.96 Retail: $355.95

OPGI Price: $322.99


Part Type: (P) High Performance, designed to improve performance
Years: Sold As: SET
2015 Tempest Catalog Page: 307
2016 Tempest Catalog Page: 313


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

  • NOTE1: These high-performance items are not eligible for any further discounts or promotional pricing.

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.

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