There are many theories on how the air fuel ratio effects the amount of power and torque an engine will make. One of the most common beliefs is that in order to achieve maximum power we need to tune the engine dangerously lean. In this demonstration we will use the torque optimisation function on our Mainline engine dyno to demonstrate the actual measurable effect of the air fuel ratio on engine torque. For this demonstration we will use our Toyota 1ZZFE engine equipped with a Link Fury ECU.