Hey motor heads: (valve) cam-less engines ...

[izzy]

Cool:

[video]http://www.youtube.com/watch?v=Bch5B23_pu0[/video]

[TyroneBiggums]

That's pretty cool, but to me it seems like a solution to a problem that doesn't really exist.

[izzy]

lol

[TyroneBiggums]

???

[izzy]

lol

lol

innovation, how the good fuck does it work?

[TyroneBiggums]

Not sure. I'm all for innovation when it actually improves existing technology. Innovation just for the sake of innovation doesn't make sense, especially when it complicates a process that already works. F1 and Moto GP engines, some of the most sophisticated in the world, work great with DOHC configurations.

From a practical sense, this system would potentially add unneeded bulk and weight. If they want to run it on air, they'd have to add an air pump, air lines, fittings on the top of the cylinder heads, etc. Not to mention you'd need some way to regulate air pressure, add a computer or some such to directly control air movement, blah blah ad infinitum.

You get the idea.

If they can circumvent all of these factors, then great, put it on my car. I just don't see it being practical for most cars however.

[marshallnoise]

http://scarbsf1.com/valves.html

This isn't new technology, but it would be a first if they were used in an actual production vehicle. I disagree that pneumatic valves are solving a problem that doesn't need fixing. There are a ton of reasons to bring this tech into standard production vehicles. But cost is the main reason why it hasn't been done.

EDIT: I suppose that system isn't a pneumatic valve system so I take back my comment above.

[TurboPablo]

Can't watch right now.

Electronic valvetrain? Servo controlled?


Been happening on boats for a long time. Camshafts aren't going away anytime soon though. GM is continually wringing more power and efficiency out of the LS lineup. The Coyote motor from Ford is killing it too.

[marshallnoise]

Can't watch right now.

Electronic valvetrain? Servo controlled?


Been happening on boats for a long time. Camshafts aren't going away anytime soon though. GM is continually wringing more power and efficiency out of the LS lineup. The Coyote motor from Ford is killing it too.

Pneumatic in the sense that there is constant pressure on the valve to be closed via oil pressure, then compressed air opens the valve pushing past the oil pressure. Presumably you can use both to change the profile ie, slow open, fast close or maybe create a hitch in the valve timing if that proves beneficiary.

[TyroneBiggums]

Can't watch right now.

Electronic valvetrain? Servo controlled?


Been happening on boats for a long time. Camshafts aren't going away anytime soon though. GM is continually wringing more power and efficiency out of the LS lineup. The Coyote motor from Ford is killing it too.

Pneumatic in the sense that there is constant pressure on the valve to be closed via oil pressure, then compressed air opens the valve pushing past the oil pressure. Presumably you can use both to change the profile ie, slow open, fast close or maybe create a hitch in the valve timing if that proves beneficiary.

In the video he said it would be held closed by an air or metal spring, not oil pressure. It would require way too much oil pressure to hold the valves close and return them to the closed position to be able to run the engine well. You'd have to run a separate oil system to achieve this I would guess.

Again, it's a cool idea, but air-actuated valves just don't seem beneficial. Typically an engine is designed to run harmoniously with itself, not like the sum of 8 individual cylinders put together.

[TurboPablo]

Can't watch right now.

Electronic valvetrain? Servo controlled?


Been happening on boats for a long time. Camshafts aren't going away anytime soon though. GM is continually wringing more power and efficiency out of the LS lineup. The Coyote motor from Ford is killing it too.

Pneumatic in the sense that there is constant pressure on the valve to be closed via oil pressure, then compressed air opens the valve pushing past the oil pressure. Presumably you can use both to change the profile ie, slow open, fast close or maybe create a hitch in the valve timing if that proves beneficiary.

In the video he said it would be held closed by an air or metal spring, not oil pressure. It would require way too much oil pressure to hold the valves close and return them to the closed position to be able to run the engine well. You'd have to run a separate oil system to achieve this I would guess.

Again, it's a cool idea, but air-actuated valves just don't seem beneficial. Typically an engine is designed to run harmoniously with itself, not like the sum of 8 individual cylinders put together.

I imagine the biggest benefit will be the ability to perfectly tune individual cylinders to compensate for differences in machinig tolerances. Still seems cost prohibitive at this point.

Also, Pneumatic-Hydraulic controls seems peculiar. You can't compress a liquid but you can a gas. So the ECU has to be fast to calculate the lift and duration ratios.

Oh, still haven't watch. I'm sick and forgot.