Camshafts are great because they’re simple and mechanical and well-proven after many, many, many, many, many, many years of engine production. But there’s a better, newer way that runs an engine without them, and here’s how it works.

This is how a camless engine works, something we’ve seen over the past four years from Swedish supercar builders Koenigsegg and the imaginatively-named FreeValve.

Put simply, instead of a metal camshaft physically pressing a valve down and open, an actuator forces the valve open with air pressure. Check out Engineering Explained’s simplified diagram to get a sense of what that looks like:

We explained a lot of this ourselves when we visited Koenigsegg back in 2014, and saw how much more efficient an engine can be operating on a much more digital/binary scale than a physical one. A valve in an engine using a camshaft gradually opens and then gradually closes, thanks to the physical design of a camshaft. A valve in a camless engine can open just about all the way instantly, and close just a well. You can change how this all looks at any RPM, you can easily cut off any cylinders individually, and you get a lot more freedom to run an engine how it would like to be run.

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At the moment the system is very new, and likely quite expensive, but hopefully its cost and complexity will go down as the tech matures.