We love horsepower. We love torque. We also need to embrace fuel economy, and that's a tricky line to toe for producers of automobiles with large engines that make loud noises for enthusiastic customers.

We currently live in an era of tremendous horsepower availability, yet our vehicles have also never been more fuel efficient. There are a whole lot of engineering tricks at play to make this possible, and Jason Fenske from Engineering Explained is here to dive into one of them.

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It's called the charge motion control valve, and it lives in the heart of the Ford Mustang GT's 5.0-liter V-8. More specifically, it sits across the intake ports of all eight cylinders in the manifold. Its task is improving fuel economy and lowering emissions, and it's quite good at achieving its goals.

As air comes in through the intake, it's directed into the intake manifold. From there, it is ported out to the eight cylinders. Before it gets there, however, it runs through the charge motion control valve. It's as if you have another set of throttle controls inside your intake manifold, and this allows greater restriction of airflow into the engine.

At low speeds, the charge motion control valve reduces airflow to save fuel. Stomp on the throttle pedal and the valve opens up to let the air flow more freely, creating more power and more fun.

Not a bad little device, really.


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