The proportion of air to fuel, by mass, present in an internal combustion engine’s mixture is a critical parameter. This metric dictates the efficiency and emissions characteristics of the engine’s operation. For example, a gasoline engine might aim for a specific ratio to ensure complete combustion, minimizing unburned hydrocarbons and carbon monoxide.
Maintaining this precise balance is vital for optimal engine performance, fuel economy, and exhaust emissions control. A deviation from the ideal value can result in reduced power output, increased fuel consumption, and elevated levels of pollutants. Historically, mechanical carburetors controlled this mixture; modern systems utilize sophisticated electronic controls to achieve more precise and dynamic regulation.