ARP 144-4002 Pro Series Cylinder Head Stud Kit Chrome Moly - 8740

The ARP 144-4002 is a professional-grade cylinder head stud kit engineered for high-performance and racing applications. Built from premium 8740 chrome moly steel, these studs are heat-treated to 200,000 psi tensile strength, offering superior clamping force and reliability under extreme combustion pressures.

Key Features:

• Premium 8740 chrome moly alloy rated at 200,000 psi tensile strength
• Vertical rack heat-treatment process ensures complete and uniform heat penetration
• Centerless ground after heat-treat for precise concentricity and perfect alignment
• Thread rolled after heat-treatment for approximately 10 times better fatigue strength
• Hex head design for straightforward installation and removal
• Undercut short studs equalize stretch for consistent clamping force
• Includes hardened parallel-ground washers for even load distribution
• Each stud individually marked with ARP stamp for quality assurance

Why Choose Studs Over Bolts:

Head studs provide superior accuracy and consistency compared to bolts because they stretch only along the vertical axis when torqued. Unlike bolts, which experience both torsional and tensile forces simultaneously, studs install finger-tight and are loaded purely in tension when the nut is torqued. This results in more uniform clamping pressure across the head gasket surface and easier engine assembly, particularly important for racing engines requiring frequent servicing.

Installation Notes:

Install studs finger-tight in a relaxed mode—never force them in with a jammed nut. The undercut design on shorter studs compensates for head gasket compression and helps prevent blown gaskets. Always re-torque after initial engine run-in to account for gasket compression.

ARP Pro Series head studs are the choice of professional engine builders across all forms of motorsports, delivering zero-defect reliability when maximum clamping force is critical.