ARP 190-3602 Cylinder Head Fasteners High Performance Series Hex Head Bolts - 8740

The ARP 190-3602 cylinder head fastener kit delivers professional-grade reliability for high-performance engine builds. These hex head bolts are engineered from premium 8740 chrome moly steel and heat-treated to 180,000 psi tensile strength—15% stronger than Grade 8 fasteners—providing superior clamping force and resistance to failure under extreme conditions.

Key Features:

• Premium 8740 chrome moly steel construction for exceptional strength and durability
• Heat-treated to 180,000 psi tensile strength for reliable performance under high cylinder pressures
• Hex head design with reduced wrenching profile and wide-area flange for easy installation
• Thread rolled after heat treatment for superior fatigue resistance and thread integrity
• Includes hardened, parallel-ground washers for even load distribution and accurate torque readings
• Allows cylinder head retorquing without valve train removal
• Centerless ground for precise concentricity and perfect alignment during assembly

Manufacturing Excellence:

ARP employs precision manufacturing processes that set these fasteners apart from the competition. Each bolt is vertically rack heat-treated to ensure complete and uniform heat penetration throughout the material. Following heat treatment, the bolts are centerless ground through multiple precision cuts to achieve exceptional straightness and concentricity. Thread rolling is performed after heat treatment—a costly but critical process that increases fatigue strength by up to ten times compared to pre-heat-treat threading methods.

Installation Benefits:

The reduced hex head design and wide-area flange allow for cylinder head service without removing valve train components, saving valuable time during engine maintenance. The precision manufacturing ensures that cylinder heads and gaskets align perfectly during assembly, eliminating the frustration of misalignment common with inferior fasteners. Each kit includes hardened washers that are parallel-ground to provide consistent torque readings and uniform clamping force across all fasteners.

Application Note:

Head bolts are ideal for applications where engine bay clearance is limited or where cylinder head removal with the engine installed is necessary. For optimal results, always follow ARP's torque specifications and re-torque fasteners after initial engine run-in to compensate for head gasket compression.

Trusted by professional engine builders across all forms of motorsport, ARP fasteners represent the gold standard in engine assembly hardware. Each component is manufactured to ARP's zero-defect, zero-failure quality standard, ensuring your engine build starts with the most reliable foundation possible.