Water injection definition
In an attempt to improve performance and allow the use of lower octane gasoline , water injection was developed. The cooling of the water vapor charge suppresses detonation . A small amount of water or alcohol-water fluid is injected into the fuel-air mixture as it enters into the carburetor . Theoretically, as the water evaporates it should cool the incoming charge which then becomes denser, leading to higher volumetric efficiency . This in turn should lead to improvements in performance and economy and allow the use of lower octane fuel because cooling of the charge suppresses detonation .