ARP 190-3601 High Performance Cylinder Head Bolt Kit 8740 Chrome Moly

The ARP 190-3601 High Performance Series cylinder head bolt kit delivers professional-grade fastening strength for demanding engine builds. Manufactured from premium 8740 chrome moly steel and heat-treated to 180,000 psi tensile strength—15% stronger than Grade 8 fasteners—these head bolts provide the reliability and consistency required for high-performance applications.

Key Features:

• Premium 8740 chrome moly steel construction rated at 180,000 psi tensile strength
• Hex head design with wide area flange eliminates need for valve train removal during retorquing
• Cold-forged for molecular integrity and superior fatigue resistance
• Thread rolled after heat treatment for approximately 10 times better fatigue strength
• Centerless ground to exacting tolerances for perfect alignment and easy assembly
• Includes hardened parallel-ground washers for even load distribution and accurate torque readings
• Undercut short bolts available in select applications to compensate for head gasket compression

ARP's precision manufacturing process ensures each fastener is vertically heat-treated for complete penetration and consistent strength. The centerless grinding process involves multiple precision cuts to produce exceptionally straight bolts that allow cylinder heads and gaskets to glide into perfect alignment. Thread rolling after heat treatment—rather than before—dramatically increases fatigue strength, though this process is significantly more expensive due to increased tooling wear.

The wide-flange hex head design is engineered for easy access and retorquing without disassembling valve train components, making maintenance faster and more convenient. Each kit includes hardened parallel-ground washers that ensure even clamping force distribution across the cylinder head surface and provide accurate torque readings during installation.

These head bolts are ideal for street performance and mild competition applications where superior strength and reliability are essential. ARP's commitment to zero-defect, zero-failure quality standards makes these fasteners the choice of professional engine builders across all forms of motorsports.