ARP 135-3604 High Performance Cylinder Head Bolt Kit Chrome Moly - 8740

The ARP 135-3604 High Performance 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 hex head bolts provide superior clamping force and reliability for high-performance applications.

Key Features:

• Premium 8740 chrome moly steel construction rated at 180,000 psi
• Cold-forged design ensures complete molecular integrity
• Thread rolled after heat treatment for superior fatigue strength
• Centerless ground for exceptional straightness and concentricity
• Hex head design with wide area flange eliminates valve train removal for retorquing
• Includes hardened parallel-ground washers for even load distribution
• Undercut short bolts available in select applications to compensate for head gasket compression

Manufacturing Excellence:

Each ARP fastener undergoes a rigorous manufacturing process that sets the industry standard. Bolts are vertically rack heat-treated to ensure complete and uniform heat penetration, then centerless ground through multiple precision cuts for exceptional straightness. Thread rolling occurs after heat treatment—a costly but critical process that delivers approximately ten times better fatigue strength compared to pre-heat-treat threading methods used by competitors.

Installation Advantages:

The precision manufacturing tolerances ensure cylinder heads and gaskets align perfectly and glide smoothly into position during assembly. The wide-flange hex head design allows for cylinder head retorquing without removing valve train components, making maintenance faster and easier. For optimal performance, install bolts to manufacturer specifications and re-torque after initial engine warm-up to compensate for head gasket compression.

ARP fasteners are the choice of professional engine builders across all forms of motorsport, delivering the zero-defect, zero-failure quality standard required for competition powerplants. Each bolt is stamped with the ARP name as assurance of authentic quality and performance.