ARP 260-4701 Head Studs for Subaru Impreza EJ20 & EJ25 DOHC WRX/STi

• Brand: ARP
• Part Number: ARP-260-4701
• Country of Manufacture: United States

ARP Pro Series head studs are engineered for high-performance Subaru EJ20 and EJ25 DOHC WRX/STi engines. Manufactured from premium grade 8740 alloy and proprietary ARP2000 alloy, these studs are rated well above standard “aircraft” quality steels. Each stud is individually placed in specialized racks and heat-treated to 190,000 psi (8740) or 220,000 psi (ARP2000), ensuring thorough heat penetration and superior strength compared to lesser alternatives.

Exacting manufacturing tolerances allow gaskets and cylinder heads to align perfectly, facilitating easier assembly and maintenance—especially important for engines requiring frequent service. Studs also provide more consistent and accurate torque loading, as the fastener is only stretched along the vertical axis during installation, unlike bolts which are twisted under torque.

ARP controls the entire manufacturing process in-house, ensuring the highest level of quality for fasteners used in everything from OEM replacements to professional motorsports applications.