After several years of testing and development, the Cosworth 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 reliability, power, and performance. Starting with a brand new Subaru EJ257 semi closed deck block, they meticulously hone each bore to guarantee perfect piston to cylinder wall clearance. The block is then assembled with Cosworth Forged Pistons, Forged H Beam connecting rods, their high performance rod and main bearings, and either a new STI Forged crankshaft or Cosworth Billet Unit. For maximum performance, an optional steel billet crank is available.

Once the cylinder block assembly is completed, they install a pair of CNC machine port-bored Big Valve Cylinder heads with Cosworth's proven S2 camshafts complete with valve lash set to their specifications. The cylinder heads are secured with Cosworth's high performance 11mm steel studs, and are sealed with multi-layer steel Cosworth head gaskets. Finally, they install 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.

Please make sure to select whether you want the 2004 - 2006 Style STi heads or the 2007 Style with the Air Injection Ports under the drop down "size" menu.

If you have any questions regarding one of these setups, please don't hesitate to give us a call at 800-830-6675!

Quantity:   Size 2004 - 2006 Style Heads 2007 Style Heads  

Quantity:   Size 2004 - 2006 Style Heads 2007 Style Heads  

Quantity:   Size 2004 - 2006 Style Heads 2007 Style Heads  

Quantity:   Size 2004 - 2006 Style Heads 2007 Style Heads  

Quantity:   Size 2004 - 2006 Style Heads 2007 Style Heads  

Quantity:   Size High Compression (9:2:1) Low Compression (8:2:1)  

Quantity:   Size High Compression (9:2:1) Low Compression (8:2:1)  

Quantity:   Size High Compression (9:2:1) Low Compression (8:2:1)