6.0in long Bolt 7/16in Diameter w/ End Cap

The Jones Racing Products 6.0in Bolt with 7/16in Diameter and End Cap (MPN: BEC-2109-E) is a precision mandrel drive bolt engineered for high-performance engine assembly and racing applications. This hex-head fastener features a stepped washer design that distributes clamping force evenly, critical for securing rotating components in competitive engine builds where vibration tolerance and repeatable torque specifications are non-negotiable.

Manufactured from steel for strength and durability, the 6-inch length and 7/16-inch diameter provide compatibility with common mandrel pulleys and harmonic balancer assemblies found in both street and race engine configurations. The integrated end cap prevents fastener migration during high-RPM operation—a critical detail that prevents catastrophic engine damage from loose hardware. The stepped washer geometry ensures positive engagement without over-tightening, preserving bolt preload integrity across thermal cycles and sustained operation.

This fastener is essential for engine builders, race teams, and performance shops performing crank pulley installation, balancer servicing, or damper assembly on domestically-sourced and import race engines. Jones Racing Products has established itself as the OEM supplier for precision fastening in the motorsports community, and this bolt maintains the exacting standards required for reliability under load.

The BEC-2109-E ships as a single unit, allowing buyers to purchase exact quantities needed for their build. Proper torque specification per engine manufacturer guidelines is required during installation to achieve designed preload without stripping the fastener or cracking the pulley hub.