There are several compelling reasons why ARP’s specially designed harmonic damper bolt should be used instead of the factory hardware. First, they’re made of heat-treated 8740 chrome moly steel that’s nominally rated at 190,000 psi tensile strength to provide high RPM security. Secondly, the increased-wrenching size, tall 12-point head facilitates turning high compression engines over by hand without fear of rounding the bolt heads. Kits include a ¼” thick wide area washer to better distribute the clamping force.
156-2502 – Harmonic Damper Bolt Kit For 5.0L Ford Coyote

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