Roger Clark Motorsport RCM157 14mm/12mm cylinder head stud kit Subaru Impreza, Forester, Legacy EJ20, EJ22, EJ25 DOHC

For: Subaru Impreza, Forester, Legacy with EJ20, EJ22, EJ25 DOHC engines (SOHC have different lenght of studs)

Designed for the ultimate in engine performance and reliability and derived from the rigors of the World Rally Championship, RCM’s 14mm/12mm Head Stud Kit has consistently proven itself as a must have component of any EJ20/22/25 engine build where 450bhp+ power output is expected. It is essential engines modified to this level have the most reliable system for clamping the cylinder heads onto the block assembly to avoid the heads lifting under load at high levels of boost pressure. The RCM 14/12mm Head Stud kit provides this peace of mind and cuts out the expense of cylinder head modification when compared to the WRC 14/14mm head stud kit.

Now used in many of the fastest and most powerful Impreza's across the globe the RCM 14/12mm Head Stud Kit is quite simply the foundation on which many of our high bhp engine conversions are built around. Replacing the conventional 11mm Subaru cylinder head bolts with a series of 14/12mm precisely manufactured super high tensile, aircraft grade S99 steel stud and nut system offers many advantages when building your engine. With a tensile strength much higher than that of the OE bolts and the increased stability provided by the RCM studs larger diameter when further combined with the more uniform clamping force provided by the stud and nut arrangement it is clear why so many successful engines run these kits!

All kits are supplied with RCM's own assembly lube, which utilizes Graphite DJ technology, ensuring you are able to install to the correct torque figures accurately.

Key features:

• Huge increase in tensile strength and yield when compared with the OE head bolts.
• Massively increased clamping load for big bhp applications.
• Eliminates cylinder head lift at high levels of boost.
• Supplied with high tensile nuts, assembly lube and installation guide.
• As used in RCM Gobstopper I + II Time Attack race cars.
• Made in the UK from high tensile aircraft grade S99 steel to WRC spec.
• Precision rolled threads for maximum strength.

Technical specification: 

• Cylinder head studs manufactured using "Aircraft Grade S99 High Tensile Steel".
• Precision rolled threads.
• Cylinder head stud thread pitch (Block End): M14X2.
• Cylinder head stud thread pitch (Cylinder Head end): M12X1.25.
• Cylinder head stud length: 197mm.
• Supplied in the kit are:
• x12 RCM 14/12mm head studs.
• x12 high tensile nuts.
• 1x Sachet of assembly lube and fitting guide for a comprehensive install.
• To allow the fitment of the RCM 14/12mm Head stud kit your engine block must be re engineered to accept the larger studs used in this kit. RCM can carry this work out for you at  additional cost (see part number RCM237 or contact us for more details).
• No modification is required to the cylinder heads and the increased stud thickness will pass through the existing cylinder head bolts without fault.