ARP 135-3710 Engine Cylinder Head Bolt Set 8740 Chrome Moly 12-Point

The ARP 135-3710 is a high-performance cylinder head bolt kit engineered for demanding applications where reliability and precision are critical. Manufactured from premium 8740 chrome moly steel, these bolts are heat-treated to 180,000 psi tensile strength—15% stronger than Grade 8 fasteners—ensuring exceptional clamping force and durability under extreme conditions.

Key Features:

• Premium 8740 chrome moly steel construction with 180,000 psi tensile strength
• 12-point head design for improved grip and reduced risk of fastener rounding
• Wide-area flanged head eliminates need for valve train removal during head retorquing
• Thread rolled after heat treatment for superior fatigue resistance
• Centerless ground for exceptional concentricity and precise alignment
• Includes hardened parallel-ground washers for even load distribution and accurate torque readings
• Cold-forged construction ensures molecular integrity throughout the fastener

Engineering Excellence:

ARP employs a vertical rack heat-treatment process that ensures complete and uniform heat penetration throughout each bolt, resulting in consistent mechanical properties. Following heat treatment, each fastener is centerless ground through multiple precision cuts to achieve near-perfect concentricity. This meticulous manufacturing process ensures that cylinder heads and gaskets align effortlessly during installation, eliminating the fitment issues common with lesser-quality fasteners.

Application:

This High Performance Series bolt kit is ideal for street performance and mild competition engines where superior strength and reliability are required. The reduced wrenching hex allows for easier installation and service without removing valve train components, making this kit particularly suitable for engines that require periodic maintenance or retorquing procedures.

Each kit includes all necessary bolts and hardened washers required for installation. For optimal results, fasteners should be retorqued after initial engine break-in to compensate for head gasket compression.