ARP 234-5203 Main Cap Bolt Kit 4-Bolt 12-Point High Performance

The ARP 234-5203 main cap bolt kit is engineered for high-performance and competition engines requiring superior clamping force and reliability. This 4-bolt main configuration features 12-point head bolts for precise torque application and improved wrenching access in tight engine compartments.

Key Features:

• Forged from premium 8740 chrome moly steel for exceptional strength and durability
• Heat-treated to 180,000 psi tensile strength for High Performance Series applications
• Precision J-form threads rolled after heat-treating deliver 1000% longer fatigue life than pre-threaded fasteners
• 12-point head design provides multiple engagement positions for easier installation
• Generous under-head radius minimizes stress concentrations
• Includes hardened, parallel-ground washers for even load distribution

ARP main bolts eliminate main cap walk and fretting while protecting engine block threads from damage during installation and removal. The post-heat-treat thread rolling process work-hardens the threads and creates a smoother, stronger surface that resists galling and cross-threading. These fasteners meet the exacting standards demanded by professional engine builders for both street performance and racing applications.