Hex Head Bolt 1/2-20 x 3 Grade 5 5pk

The Hex Head Bolt 1/2-20 x 3 Grade 5 5pk from ALLSTAR PERFORMANCE is a critical fastener for engine builds, transmission assemblies, and structural modifications where vibration resistance and tensile strength are non-negotiable. Whether you're assembling a stroker motor, reinforcing a custom chassis, or securing high-stress components in a performance application, these fasteners provide the reliability that separates amateur builds from professional-grade work. This five-pack offers the quantity most enthusiasts need for a single project without excessive bulk.

Grade 5 bolts deliver approximately 130,000 PSI minimum tensile strength, making them suitable for medium-to-high stress applications where standard Grade 2 fasteners would fail under load. The 1/2-inch diameter and 3-inch length accommodate common engine block bolt holes and transmission pan mounting points, while the 20 threads-per-inch pitch ensures fine engagement that resists loosening during thermal cycling and mechanical vibration. The zinc-plated finish provides corrosion protection for underhood and engine bay environments, preserving structural integrity over seasons of driving and storage.

Performance mechanics and engine builders rely on Grade 5 hex head bolts for intake manifold work, exhaust system anchoring, and block-to-bellhousing fastening in both carbureted and fuel-injected platforms. These bolts work with standard 3/4-inch sockets and wrenches, making installation and removal straightforward without specialty tools. Proper torque sequencing and thread-locking compound are recommended for critical applications to maximize clamping force and eliminate vibration-induced failures common in high-horsepower builds.