The ignition coil steps up the 12 volts available from the battery or alternator to a voltage of 30,000 or more volts at the spark plug. Converting a lower voltage input into a higher voltage output makes the ignition coil a step-up transformer.

The crankshaft converts the reciprocating motion of the piston into the rotational motion that's used to power the vehicle and its components.

The stoichiometric ratio defines the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air. For gasoline fuel, the stoichiometric ratio is about 14.7:1 or for every one gram of fuel, 14.7 grams of air are required. Too much air results in a lean air-fuel mixture that burns more slowly and hotter while too much fuel results in a rich mixture that burns quicker and cooler.

A head gasket is a gasket that sits between the engine block and cylinder heads to seal the cylinders to ensure maximum compression and avoid leakage of coolant or engine oil into the cylinders.

The muffler follows the catalytic converter and absorbs sound to help quiet load exhaust. It is followed by the exhaust pipe which is the final exit point for exhaust gas from the vehicle.