ARP 271-4701 Pro Series Cylinder Head Stud Kit Undercut - 12-Point ARP2000

The ARP 271-4701 is a premium Pro Series head stud kit designed for high-performance and racing engines that demand the ultimate in reliability and clamping force. Manufactured from ARP2000 material rated at 200,000 psi tensile strength, these studs feature undercut shanks and 12-point nuts for maximum durability and ease of installation.

Key Features:

• ARP2000 material with 200,000 psi tensile strength for exceptional reliability
• Undercut stud design equalizes stretch and provides more consistent clamping force
• 12-point nuts for improved grip and reduced risk of rounding
• Cold-forged construction ensures molecular integrity
• Heat-treated prior to thread rolling for superior fatigue strength
• Thread rolled after heat-treat for 10x better fatigue life compared to pre-heat-treat threading
• Centerless ground for exceptional straightness and concentricity
• Includes hardened parallel-ground washers for even load distribution

Benefits of Head Studs vs. Bolts:

Head studs provide superior clamping accuracy compared to bolts because they stretch only along the vertical axis during torquing, while bolts experience both torsional and tensile loads simultaneously. This results in more accurate and consistent torque readings. The undercut design on shorter studs helps equalize stretch across all fasteners, compensating for head gasket compression and reducing the risk of blown gaskets. Studs also simplify engine assembly by allowing cylinder heads and gaskets to align properly and glide into position.

Installation Notes:

Studs should be installed finger-tight in a relaxed mode—never cranked down with a jammed nut. After initial torquing, always re-torque studs after the engine has been run to compensate for head gasket compression. The 12-point design and wide flange eliminate the need for valve train removal when re-torquing cylinder heads.

ARP Pro Series fasteners are manufactured to zero-defect, zero-failure quality standards, making them the choice of professional engine builders across all forms of motorsports.