The engine block used in the WRC Focus was manufactured using CGI, compacted graphite iron, instead of standard grey iron to provide a stronger lighter engine block. There are several noticeable differences in the block when compared to a stock Zetec or even the Cosworth CGI engine block.

The most noticeable difference is the extended cylinder liners requiring the use of a special aluminum alloy block adapter to provide sealing to the cylinder head.





Additional changes were made to the YC block such as the lack of an oil filter mounting boss. This was done as the engine was not intended to use a conventional wet sump oiling system. The engine was designed with a special front cover seal the front of the block.





A tear drop shaped water inlet requiring a special water pump housing.





The removal of common mounting bosses used for the AC brackets and other accessories.





The gear box mounting points were also changed. The removal of the lower right mounting arm presents its own challenges. It would also be good to note that the rear main seal retainer bolts are 6mm instead of the standard 8mm. These can be drilled out and an 8mm Heil-coil installed to accept a standard rear main seal retainer.