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How come auto manufacturers aren't using camless valvetrains by now?

I'm not educated on every aspect of this technology but I get the general idea; The camshafts are removed from the equation and replaced by electric solenoids. This frees up a sizable amount of hp and allows for complete variable control of the valve timing by the ECU and gets rid of the timing belt in the process. This in turn yields more torque throughout the rev range and increases fuel economy. I saw it once years ago in a magazine. A guy had designed it himself and had a working version on his custom built engine. Seems like combining this technology with direct injection we could really improve on the combustion engine.

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What MConte said. It's still prohibitively expensive for a consumer application at this point.

Someone who follows Formula 1 closer than I do can say this for sure, but I believe all F1 engines now have electrically-actuated valves, primarily because of valve float. I think they got to a point where the engines were spinning so fast that no valve spring could close the valve fast enough.

But I don't think we're far off, honestly. As I was talking about here, Nissan and BMW are already using VVT that's so variable that you're controlling valve timing with your right foot. Throttle bodies are rendered unnecessary, except as a safety measure should the VVT system fail.

Pretty cool technology for sure. I forgot about the throttle body bit.

F1 still uses camshafts, but instead of a metal spring they use pneumatic cylinders.

Good to know.

But I wonder why they don't use desmodromic valves. I would think that would be less complex and/or more reliable.


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It seems to me like a pneumatic cylinder is probably less complex than the desmodromic valves. The desmodromic valves just sound like a huge nightmare.

The pneumatic system is pretty simple and probably weighs less too:

Yeah, and there's also more load on the camshafts with the desmodromic valves too, come to think of it, since they have the responsibility of both opening and closing the valves. That's not an issue with the pneumatic valves.

Nonetheless, Ducati has been racing quite successfully with desmodromic valves, according to that Wikipedia article.

The Ducati deso's require frequent valve adjustments. Like every 15k, or something.
Jamal, what you pictured is a hyd valve spring but still relies on the mechanical cam to open the valve.

Um, did you read my post or the caption in that diagram?

jamal wrote:Um, did you read my post or the caption in that diagram?

Did I miss something? I thought we were discussing electric/hydraulic actuated valves.

Here's a great example of this technology in action. Koenigsegg has been working on it and seems to have it pretty figured out. Capable of 20,000 RPM! I like the way this guy explains it. He says to picture an artist trying to play a piano with a broomstick across all the keys and now with camless technology is he can now play nearly limitless variants of music.

https://www.youtube.com/watch?v=Bch5B23 ... e=youtu.be

With this technology and direct injection I'm sure you could easily run a 600cc 2 cylinder engine in my metro and get 70 mpg making 60+ hp.

That Free valve technology is amazing!!

I just saw that and was gonna post it here. Its awesome to see a working example. And the added benefits that come with it! Like storing compressed air on board and using it to boost intake pressure. This is definitely the future of the internal combustion engine.

It seems as though if a smaller manufacturer can pull this off why hasn't toyota or ford or gm done it? They've put 60,000 km on that retrofitted head with no problems. Increased torque/hp/mpg and a lighter smaller engine seems like a no brainer. Especially when this system can function at 20,000 rpm.