Compression ratio

The compression ratio is a key specification in internal combustion engines, representing the ratio between the maximum volume of the cylinder (when the piston is at the bottom dead center) and the minimum volume (when the piston is at the top dead center). This measurement indicates how much the air-fuel mixture is compressed during the compression stroke. A higher compression ratio typically leads to better engine efficiency and performance because it increases the pressure and temperature of the mixture before ignition, resulting in faster combustion and more power output. However, there are limits. If the compression ratio is too high, it can cause issues like engine knocking or pre-ignition, which can damage the engine over time. Additionally, modern engines must balance high compression ratios with emissions regulations, as higher compression can also lead to increased pollutants. Engineers carefully design engines to optimize this ratio for both performance and environmental compliance.