Delphi’s Dynamic Skip Fire, or Dynamic Fuel Management in General Motors lingo, will make its production debut in the 2019 Chevrolet Silverado and 2019 GMC Sierra. The system can cut up to seven cylinders in real time to provide a healthy boost to fuel economy in the bot trucks’ V8 engines.
How does this intricate system work? Engineering Explained tackled the technology in a recent video to, well, explain how it works.
The system works by closing off the intake and exhaust valves, and each individual cylinder sports a locking pin. The pin acts as a hinge to control Dynamic Fuel Management.
In regular operation, the engine’s camshaft rotates and presses down on a deactivation arm that opens up the intake and exhaust valve. All the while, oil pressure keeps the aforementioned locking pin in place.
Now, when it’s time to deactivate one or more cylinders, the system determines which aren’t needed and which must be fired to maintain engine balance and the power. Once determined, and this is happening on the fly, oil pressure will press the locking pin back and it will no longer hold the deactivation arm. Thus, as the camshaft rotates, the valve isn’t activated and the cylinder won’t fire. It’s all much clearer in the video graphics.
The system won’t make smaller engines as efficient as larger engines, however. In GM’s 5.3-liter and 6.2-liter V8 engines, drivers may see fuel economy gains from 5 to 20 percent from the previous trucks equipped with the engines. And that doesn’t account for any weight loss or aerodynamic improvements in the 2019 Silverado and Sierra.