In order for a car
to accelerate, air must enter the combustion chambers
to mix with the fuel. In internal combustion engines
, air initially enters the engine
through an apparatus known as a throttle body
. When you mash the accelerator pedal
, the throttle cable pulls on the throttle position spring, causing the throttle pivot to turn. This rotates the throttle plate so that it is "wide-open", allowing unrestricted
airflow into the intake manifold
So, whenever you hear a racer say, "Yeah, he began to gain on me, so I went WOT and smoked his ass," you know exactly what they mean.
See throttle body for more details on how it functions.
The question arises, then, if going WOT often can have a negative impact on the life of your automobile. The answer is an unequivocal yes.
Aside from starting up your car, the greatest damage to it occurs when you accelerate. If a car spent 3,000 miles nonstop at 3,000 RPM doing 65 miles per hour, you wouldn't have too many problems. But when you are idling at a street light and accelerate, your transmission has slight stress put on it, oil pressure jumps, and all the parts in the engine begin working furiously.
Engines are designed to handle this sort of stress, but it becomes a whole other level when you go WOT and accelerate to the limit. Approaching your engine's redline, much more stress is put on the valvetrain, and the transmission's shifts come at a quicker pace.
In a nutshell, WOT should be reserved for circumstances where maximum acceleration is absolutely necessary, and when it is not, should be avoided to extend the life of your car.