ARP 156-2501 Harmonic Balancer Bolt Kit with Square Drive

The ARP 156-2501 is a high-strength harmonic balancer bolt kit engineered to withstand the extreme kinetic energy absorbed by the balancer as the crankshaft flexes and twists. These ultra-strong bolts are rated at 200,000 psi tensile strength, allowing maximum clamping force to ensure the balancer remains locked in position under the most demanding conditions.

Key Features:

• 200,000 psi tensile strength for superior clamping force
• 12-point head design accepts deep sockets and resists stripping
• 1/2" square drive forged into bolt head for engine rotation with standard 1/2" drive ratchet or breaker bar
• 1/4" thick wide-area washer distributes load evenly
• Extra tall head provides enhanced tool engagement
• Constructed from heat-treated 8740 chrome moly steel
• Heavy-duty black oxide finish for corrosion resistance

This square drive version combines the strength of ARP's premium balancer bolts with the convenience of a built-in 1/2" square drive, enabling easy rotation of the crankshaft assembly during engine building, installation, or maintenance procedures. The forged square drive eliminates the need for separate rotation tools while maintaining the bolt's structural integrity.