The engine block is known to be the largest piece of metal in a car and also one of the most important parts of the engine in which all other components are located such as cylinders and pistons. It is mounted there and it also contains small holes that serve as a passage to circulate the coolant around the engine to regulate/control the engine temperature. The engine block is where combustion energy is then transferred to mechanical energy through the rotation of the crankshafts which then cause the pistons to rotate up and down that drive the propeller/transmission system that moves the car. In previous engine block designs, most were made from iron, but nowadays engine blocks are made from lightweight aluminum alloy materials to reduce the weight of the car, which contributes to good performance (found mainly in sports cars). Cars equipped with aluminum engine blocks consume less fuel while producing fewer emissions than those equipped with iron engine blocks. But generally speaking, most cars use iron engine blocks because they are cheap....