Cosworth Long Block Big Valve Cylinder Heads KK3920 Camshafts STD Crankshaft 9.2:1 CR Subaru EJ25 2.5L 04-06
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 Cosworth's skilled craftsmen using the finest components from their 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 Cosworth’s Forged Pistons, motor sport grade Forged H Beam connecting rods along with 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, they install a pair of CNC machine port-bored Big Valve Cylinder heads with their proven S2 camshafts complete with valve lash set to our specifications. The cylinder heads are secured with high performance 11mm steel studs and sealed with multi layer steel head gaskets. Finally, Cosworth installs one of their 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 caseCosworth 79mm or 81mm Billet CrankshaftCosworth Forged H-beam Connecting RodsCosworth Forged Pistons and ringsCosworth motorsport Tri-metal bearingsBalanced to within .5 gramComplete blue-print assemblyEnlarged Intake and Exhaust portsLarge diameter stainless steel intake valvesLarge diameter Inconel exhaust valvesHi Rev Dual valve springsTitanium RetainersHardened Steel spring platformsMulti angle valve jobCNC Machined port finishKnife edge port dividerCosworth S2 High lift camshafts - KK3766Valve lash setCosworth high pressure oil pumpCam coversCosworth serial number
About Manufacturer: Cosworth
Over the last 50 years Cosworth have developed an in-depth knowledge of engines, electronics and a range of high performance technologies. This has been used to supply some of the most successful motor sport teams and vehicle manufacturers in history.
Our unprecedented success has fueled customer demand globally from diverse market sectors designing and developing technologies and components for aerospace, automotive, defense and sport applications.