Stage X 14/12mm Cylinder Head Stud Kit

The Stage X 14mm/12mm Head Stud Kit is designed for maximum engine performance and reliability, and suits any EJ20/22/25 build where 450+ bhp is expected.

Engines modified to this level need the most reliable system for clamping the cylinder heads to the block, so the heads do not lift under load at high boost pressure. Compared with the 14/14mm head stud kit, the 14/12mm kit also avoids the cost of cylinder head modification.

Replacing the standard 11mm Subaru head bolts with 14/12mm precision-manufactured, super high-tensile, aircraft-grade S99 steel studs and nuts offers many advantages when building an engine.

It gives a tensile strength much higher than the OE bolts, more stability from the larger stud diameter and a more uniform clamping force from the stud and nut arrangement.

Supplied with graphite-based assembly lube, so the correct torque figures can be reached accurately.