Cosworth CS600X Long Block Assembly 81mm Stroke w/ Big Valve Cylinder heads and KK3766 Camshafts- 81mm Billet Crankshaft Subaru WRX STI EJ25 US & Euro spec 07

After several years of testing and development, the Cosworth CS600 series High Performance Subaru EJ25 long block has arrived. The CS600 series is designed for extreme track day use and the demanding performance enthusiast. Each assembly is precision built by one of Cosworths skilled craftsmen using the finest components from our parts catalog to ensure maximum reliable power and performance. Starting with a new Subaru EJ257 semi closed deck block, we meticulously hone each bore to guarantee perfect piston to cylinder wall clearance. The block is then assembled with our Forged Pistons, motorsport grade Forged H Beam connecting rods along with our high performance rod and main bearings and a new STI Forged crankshaft. For maximum performance, an optional steel billet crank is available (CS600X). Once the cylinder block assembly is completed, we install a pair of our CNC machine port-bored Big Valve Cylinder heads with our proven S2 camshafts complete with valve lash set to our specifications. The cylinder heads are secured with our high performance 11mm steel studs and sealed with multi layer steel head gaskets. Finally, we install one of our blue-printed, high pressure oil pumps for maximum lubrication. This proven engine combination has been used by top teams to win events in both North America and Europe and is available now for general sale.

- New Subaru EJ25 STI Engine case
- Cosworth 81mm Billet Crankshaft
- Cosworth Forged H-beam Connecting Rods
- Cosworth Forged Pistons 99.5mm (8.2:1)
- Cosworth motorsport Tri-metal bearings Balanced to within .5 gram
- Complete blue-print assembly Enlarged Intake and Exhaust ports.
- Large diameter stainless steel intake valves.
- Large diameter Inconel exhaust valves.
- Hi Rev, Dual valve springs
- Titanium Retainers
- Hardened Steel spring platforms
- Multi angle valve job
- CNC Machined port finish
- Knife edge port divider
- Valve lash set
- Cosworth high pressure oil
- Cam covers
- Cosworth serial number

About Manufacturer: Cosworth
Over the years we have developed in-depth knowledge of engines, engine components and engine management systems. This has been successfully used to supply engines to some of the most successful Formula One teams and vehicle manufacturers. Our unprecedented success in the performance market has fueled customer demand from diverse market sectors. In addition to the traditional markets, Cosworth is engaged in designing and developing, engines and components for marine, locomotive and aerospace applications.

A rigorous and comprehensive product quality assurance policy is implemented across our business. Quality engineering is embedded in processes, procedures and team ethic; we operate under recognised quality management systems.