Designed for the ultimate in engine performance and reliability and derived from the rigors of the World Rally Championship, RCM 14mm/14mm Head Stud Kit has consistently proven itself as amust havecomponentof any EJ20/22/25 engine build where 500bhp+ 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 14/14mm Head Stud kit provides this peace of mind!
Now used in many of the fastest and most powerful Imprezas across the globe the RCM 14/14mm Head Stud Kit is quite simply the foundation on which all our high bhp engine conversions (including Gobstopper and Gobstopper 2) race engines are built around. Replacing the conventional 11mm Subaru cylinder head bolts with a series of 14mm 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 championship winning 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.
- Cylinder head studs manufactured using "Aircraft Grade S99 High Tensile Steel" to WRC specification.
- Precision rolled threads.
- Cylinder head stud thread pitch (Block End): M14X2.
- Cylinder head stud thread pitch (Cylinder Head end): M14X1.5.
- Cylinder head stud length: 197mm.
Inluded in this Kit
- 12 x RCM 14mm head studs.
- 12 x high tensile nuts.
- 1 x Sachet of assembly lube and fitting guide for a comprehensive install.
To allow fitting of the RCM 14/14mm 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).
Due to the increased diameter of the cylinder head stud machining is required to the cylinder heads. The original head bolt passages must be drilled out to a larger diameter in order for the 14mm stud to pass through.
Non RCM manufactured head gaskets used alongside this kit will require slight modification using our tapered reamer tool (See part number RCM910).
4x RCM658 modified head location dowels are required when using this kit (Sold separately).
WARNING: Operating, servicing and maintaining a passenger vehicle or off-road vehicle can expose you to chemicals including engine exhaust, carbon monoxide, phthalates, and lead, which are known to the State of California to cause cancer and birth defects or other reproductive harm. To minimize exposure, avoid breathing exhaust, do not idle the engine except as necessary, service your vehicle in a well-ventilated area and wear gloves or wash your hands frequently when servicing your vehicle. For more information go to https://www.P65Warnings.ca.gov/passenger-vehicle.