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    Head Studs, M156


    Availability: In stock


    Head Studs, M156

    Weistec has exclusively partnered with ARP, the top name in performance engine hardware. Head studs are used to fasten the heads to the block in place of the factory head bolts. The connection between the cylinder heads and the block is a complex part of the engine. Coolant and oil flow back and forth between the block and the cylinder heads. The head gasket keeps the coolant, oil, and air charge in the cylinders separate from each other with the help of pressure generated by the head bolts. The factory head bolts are "torque to yield" meaning that when installed, they are tightened to the point where they permanently stretch. There have been stock M156 oil leak issues resulting from a poor connection between the cylinder heads and the block which in part can be attributed to the head bolts.

    With 260,000+PSI of tensile strength, our ARP 625+ head studs are able to hold down the heads with far greater pressure than the factory head bolts, without permanent stretching. The result is a more reliable performance engine that will not be susceptible to leaks between the heads and block. Quality head studs are among the top items in the list of parts that allow an engine to reliably reach high power levels.

    Key Features:

    • 260,000 psi Tensile Strength

    • 255,000 psi Yield Strength

    • Complete replacement of factory head bolts

    • Improved Head to Block connection eliminating leaks

    • Reusable, unlike the factory bolts which are "one time use"

    PDF Filem156hs (495.6 KB)Download

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    Weistec Engineering performance upgrades may be used solely on vehicles used in sanctioned competition which may never be used upon a public road or highway, unless permitted by specific regulatory exemptions. For state specific details please visit the following website.
    It is the responsibility of the installer and/or user of the product to ensure that it is used in compliance with all applicable laws and regulations. If a product was purchased in error, do not install and/or use it. The purchaser must arrange to return the product(s) for a full refund.
    This policy only applies to installers and/or users who are in the United States, customers who reside in other countries should act in accordance with their local laws and regulations.
    All performance modifications and installations are at the customer’s own risk. Weistec Engineering holds no responsibility either implied or otherwise for mechanical, electrical or other failure when using any aftermarket performance products.