The engine block is cast iron, with high
mechanical strength.The crankshaft is supported by means of
five main bearings (1).The cylinders are formed directly in the
engine block, and are graded into three sizes plus one oversize.The engine block also houses the two counter-rotating
shafts, which are supported by a central bush and a ball bearing
at the front and rear.There are special channels in the engine
block walls which allow the flow of coolant and lubricating oil.At the bottom of each cylinder, there is
a jet (2) from which oil is sprayed onto the piston crown.