5/16-18 x 1.250 12pt Bolt ARP2000

The 5/16-18 x 1.250 12pt Bolt ARP2000 is a premium fastener engineered for high-performance engine builds, racing applications, and critical structural assemblies where standard steel bolts fall short. Manufactured by ARP (Applied Racing Products), a leader in fastener metallurgy, this bolt serves builders and technicians who demand superior clamping force, fatigue resistance, and reliability under extreme operating conditions. Whether you're assembling an engine block, cylinder head, or high-load bracket, this 12-point head bolt delivers the predictable performance required in motorsports, marine, and industrial environments.

Forged from ARP2000 alloy steel, this fastener offers tensile strength and fatigue resistance that significantly exceed grade 8 specifications, making it ideal for applications subject to cyclic loading and vibration. The 5/16-18 unified national coarse thread provides robust engagement with standard tapped holes, while the 1.250-inch length accommodates common engine block and head dimensions. The 12-point head design—also called a shallow 12-point or universal head—allows use with both 3/8-inch and standard wrenches and sockets, reducing inventory needs while providing superior grip geometry that minimizes corner rounding during installation and removal, a critical advantage in tight engine compartments.

Buyers assembling small-block or big-block engines, LS platforms, or any performance application requiring ARP-quality fasteners will recognize this bolt as a direct replacement or upgrade from OEM hardware. Proper installation requires a calibrated torque wrench and, if specified by engine manufacturer, ARP's fastener lubricant to achieve consistent clamping load and preload. The lightweight 0.04-pound specification per bolt makes it suitable for weight-sensitive builds. Each bolt is individually supplied, allowing custom kit assembly or single-unit replacement in existing engine builds.