SBC HP Harmonic Balancer Bolt Kit

The Pioneer SBC HP Harmonic Balancer Bolt Kit (Part No. 859012) is a precision fastener engineered for small-block Chevy harmonic balancer installation and retention. This 7/16-20 thread fastener measures 2.500 inches in length with a 5/8-inch hex head and is constructed from steel with cadmium plating for corrosion resistance. Designed to OEM specifications, this bolt delivers the secure, vibration-dampening connection critical to engine balance and longevity in both street and race applications.

The harmonic balancer bolt's cadmium finish provides superior protection against corrosion and oxidation compared to bare steel, essential for engines exposed to moisture, salt air, or extended storage. The 7/16-20 thread specification ensures compatibility with small-block Chevy crankshaft snouts, while the 5/8-inch hex head accepts standard socket and wrench sizes for straightforward installation and future service. At just 0.33 pounds, the kit is compact and easy to transport or stock as a spare.

This fastener is essential for engine builders, restoration specialists, and small-block Chevy enthusiasts performing harmonic balancer replacement or initial assembly. Whether rebuilding a 350, 383, or other small-block variant, proper harmonic balancer fastening prevents crankshaft runout and eliminates vibration-related wear on bearings and seals. Technicians restoring vintage performance vehicles or maintaining contemporary Chevy mills rely on OEM-specification fasteners like the Pioneer 859012 to ensure precision fitment and long-term reliability.