Fully digital valve trains... 12 stroking anyone?!?

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Here's a nifty little article on the development of a fully digital valve train using digitally driven camshafts and desmodromic cams.

Digital Valve Trains

They have bulit and dyno'd several working models and claim they're targeting the existing market to add their technology to help optimize engine cycles.

Shifting from 4-stroke to 2-stroke for short bursts of acceleration and cyclider deactivation across all cylinders intermittently to help prevent oil accumulation amongst other benefits are being claimed here. 12 stroking?!?
 
Toyota is getting a lot of efficiency improvements by implementation of significant cam timing changes, coupled with a basic good engine design. 42% thermal efficiency, and over a very wide range too. The 2.5 in the new Camry is a great example. 40 real world MPG in a full sized, non hybrid car.

With that in mind, there is little improvement left. Thermal efficiency can reach about 50% in larger engines and/or ultra high tech engines (such as F1 stuff) , and the absolute theoretical thermal cycle engine Carnot limit is an unachievable 60%.

So, electric valves, with all their promise, will not be a game changer. Engine efficiency is well understood and near ideal performance is already possible.

Note: I have a background in camshaft dyno testing (in a past life) . Clearly, cam profiles change engine output markedly. But displacement is always a limiting factor. 100% volumetric efficiency is a practical maximum at any RPM. Put another way, a 1.2L, 3 cylinder engine cannot produce the low end torque of a conventional, well tuned, 2.5L engine, despite every trick in the book.

What that 1.2L engine can do is match the 2.5's peak output, this is done via extra RPM.

It's no surprise Ford uses turbochargers and small engines with high compression. An easy way to reduce frictional losses.
 
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I think it would be great for aftermarket tuning and computers. Have an ecm that you can select hwy driving , and shorten the cam duration and lift. For performance more duration. Even overlap. All without major mechanical changes.
 
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A Scandinavian company has been running engines with electronic valve actuation for several years now. Wish I could remember their name. They also produce a very fast sports car. Ed
 
Originally Posted By: Eddie
A Scandinavian company has been running engines with electronic valve actuation for several years now. Wish I could remember their name. They also produce a very fast sports car. Ed
Koenigsegg
 
Originally Posted By: Imp4
Here's a nifty little article on the development of a fully digital valve train using digitally driven camshafts and desmodromic cams.
Digital Valve Trains
They have bulit and dyno'd several working models and claim they're targeting the existing market to add their technology to help optimize engine cycles.
Shifting from 4-stroke to 2-stroke for short bursts of acceleration and cyclider deactivation across all cylinders intermittently to help prevent oil accumulation amongst other benefits are being claimed here. 12 stroking?!?


Really interesting, but I wonder what it will do to the cost of repairs!
 
Mobil 1, because of 0s and 1s in binary.
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The negative aspect is that the "heads" look to be very tall.
I doubt you could put heads like this on a LT4 and put the engine under the bonnet in a C7.
 
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