ARP Head Stud Kit for Subaru Impreza WRX STi 2.0L EJ20 2.5L EJ25 2.5L EJ257 CA625+

ARP’s Custom Age 625 Plus material is newly formulated super-alloy demonstrates superior fatigue cycle life, tensile strength and toughness – with complete resistance to atmospheric corrosion and oxidation.
ARP is the first to develop manufacturing and testing processes for fasteners with Custom Age 625+.
Best of all, it is less expensive and expected to soon replace MP-35 as the material of choice in the high strength, super-alloy field. Typical tensile strength is 280,000 psi.

Includes:
Custom Age 625+ studs
Parallel Ground Washers
8740 Chrome Moly Steel 12 pt Nuts
1/2 oz. Arp Ultra-Torque Assembly Lube