Engines are complicated things. While their general operating principles are widely understood by many, the more intricate aspects that go into making them work at peak efficiency are less well-known. One example is the work carried out by manufacturers, motorsports teams and specialist test houses to determine the exact amount of air needed to boost engine performance.
Effective combustion requires a balance of three elements, namely fuel, air and a source of ignition. For maximum combustion efficiency to be achieved, there needs to be the perfect ratio of between the three, the so-called ‘stoichiometric fuel ratio’.
For vehicle engines, this perfect mix typically requires a ratio of around 14.7 parts of air to 1-part fuel, though this may vary according to the type and composition of the fuel being used. For optimum performance, it is especially important to get the right balance. If there’s too much air, then the engine will run lean, manifesting itself in symptoms such as reduced power for acceleration and back-firing or popping when slowing down.
At the other extreme, if there’s too little air, then the mixture will be fuel-rich, manifesting itself in problems including reduced performance, poor fuel economy and increased carbon emissions.
Read the full article in the January 2020 issue of DPA.