Opposed cylinder designs place cylinders flat in two rows 180° opposite each other with a single crankshaft running between them.

A v-arrangement has two rows of cylinders in a V-shaped block with a crankshaft at the bottom of the V. Any even number of cylinders is possible in this configuration from the V-2 that's commonly used in motorcycles up to V-12 or bigger for large trucks. The V design produces a shorter engine than an in-line cylinder configuration and allows for better air-fuel distribution.

The intake manifold distributes outside air to the intake ports on the cylinder heads. The intake air filter removes any airborne contaminants before the air enters the engine.

Modern car engines are cooled by liquid which circulates through the engine block and cylinder heads absorbing excess heat. This liquid is made up of half water and half antifreeze (commonly, ethylene glycol) which both keeps the water from freezing at low temperatures and raises its boiling point making heat transfer more efficient.

The catalytic converter converts pollutants in exhaust gas into less pollutant substances like carbon dioxide and water.