The Best Way To Compare Engine Efficiency - BSFC

Brake Specific Fuel Consumption (BSFC) is a great way to compare the efficiency of engines. It's often referred to in units of g/kWh, (for example: 200 g/kWh) and represents the amount of fuel flowing into the engine versus how much power the engine actually makes. BSFC is directly correlated to the efficiency of an engine. The lower the BSFC, the more efficient an engine is.

In this video we'll define brake specific fuel consumption, show how it correlates with efficiency, look at a BSFC map, compare BSFC with RPM, air-fuel ratio, and engine size, and talk about ways of optimizing BSFC. We'll also look at how you can analyze the BSFC of your car engine if you have an MPG readout. This is helpful in determining what the best gear to be in for maximum efficiency.