The air-fuel ratio has a significant impact on the brake horsepower (BHP) of an engine. BHP is the power produced by the engine at the crankshaft, and it is measured in horsepower (hp). The ideal air-fuel ratio for maximum BHP is typically between 12.5:1 and 13.5:1. This ratio provides the optimum balance of air and fuel to produce the most power. When the air-fuel ratio is too rich (too much fuel), the engine will produce less power because the excess fuel will not burn completely. When the air-fuel ratio is too lean (too much air), the engine will also produce less power because there will not be enough fuel to burn.
SFC:
The air-fuel ratio also affects the specific fuel consumption (SFC) of an engine. SFC is the amount of fuel consumed by the engine per unit of power produced, and it is measured in grams of fuel per kilowatt-hour (g/kWh). The ideal air-fuel ratio for minimum SFC is typically between 14.7:1 and 15.2:1. This ratio provides the optimum balance of air and fuel to produce the most power while using the least amount of fuel. When the air-fuel ratio is too rich, the engine will use more fuel because the excess fuel will not burn completely. When the air-fuel ratio is too lean, the engine will also use more fuel because there will not be enough fuel to burn.
In summary, the ideal air-fuel ratio for maximum BHP is typically between 12.5:1 and 13.5:1, while the ideal air-fuel ratio for minimum SFC is typically between 14.7:1 and 15.2:1.
