Subaru Head Stud Kit - EJ DOHC Series

The Subaru Head Stud Kit – EJ DOHC Series is a critical fastener upgrade for Subaru enthusiasts pursuing reliable high-performance engine builds. Designed by ARP, a leader in precision fastening technology, this kit replaces factory head bolts with superior studs engineered to withstand elevated boost levels, high horsepower applications, and extreme combustion pressures. Whether you're building a turbocharged performance engine or restoring a classic EJ-platform Subaru, head studs eliminate the risk of fastener failure that can lead to catastrophic engine damage or gasket blow-out.

ARP head studs deliver superior clamping force consistency compared to traditional bolts because studs are not torqued through the fastener itself—they are pre-tensioned under the nut, resulting in more accurate preload and reduced relaxation over engine cycles. The EJ DOHC series kit is precision-manufactured to OEM specifications for the Subaru EJ dual-overhead-cam engine family, ensuring proper fit and alignment during installation. ARP's proprietary heat-treating and surface finishing processes enhance fatigue resistance and corrosion protection, making these studs suitable for street, track, and forced-induction applications where reliability cannot be compromised.

This head stud kit benefits engine builders, performance tuners, and Subaru owners planning significant power modifications or restoration work on EJ DOHC platforms including WRX, STI, Forester XT, and Legacy GT models. Professional installation is recommended to ensure correct torque sequence and preload specifications, which are critical to cylinder head sealing and engine longevity. The kit's compact 4.35 x 2.3 x 8.8-inch package ships ready for immediate installation, making it an essential component for any serious Subaru engine build targeting reliability above factory specifications.