Freevalve engine

Very impressive.

A very old (and obvious) idea, probably going back to the 19th century. It certainly has benefits but is not the right thing for an aero engine. A geared camshaft with lobes and rockers is about the most reliable setup there is.

It’s hard to get reliable enough for even a car. No vendor has decided to do it so far. The problems must be huge because if you look at how complex modern engines are with variable valve timing via multiple camshaft lobes, it would be such an obvious solution.

Christian is a very forward thinking and impressive man. He built that company from absolutely nothing, starting literally in an old barn. I have huge respect for him and what he’s accomplished. That said, his personal car is a Tesla Model S… He says that electric is absolutely the future, except, funnily, for supercars. His theory is that supercars are like Swiss watches and will remain mechanical. That’s what will set them apart and provide the craftsmanship in a world where everyone else has the same batteries and same electric motors in their car. It’s an interesting theory, but I’m not sure he’s entirely correct. He’s already made a hybrid supercar that doesn’t have a gearbox. It basically starts and lives constantly in 6th gear, but has a torquey electric motor connected to the engine to help it accelerate through the lower regions. Works very well.

In any case, his approach to engineering is always interesting and many of their inventions will probably trickle down like in the example above.

Just watched the video. Yes – having electrically operated valves is really obvious. I recall having a conversation in 1973 with a design engineer at a firm I worked at during college/univ holidays, asking whether anyone had tried to electrically actuate the valves. I suggested converting a Yamaha 4-stroke motorbike engine… he just laughed and said “you will smash it up” No doubt he was right. Especially if the compression is high enough to require a “negative clearance” between a valve which is open at the wrong time and the piston… I think that’s true for most car engines; not sure if it is true for the old Lycos etc.

achimha wrote:

It’s hard to get reliable enough for even a car

That may be true right now, but it’s not hard to see that changing. Modern electrically operated fuel injectors, for example, are incredibly reliable over millions over cycles and that was probably unimaginable a few decades ago. I don’t see anything in pneumatic valvetrain that makes it inherently destined to forever be unreliable.

And an appropriate failsafe design would only lead to loss of one cylinder not an engine stoppage.

PS. You say “even a car” as if they are less reliable than our aero engines???

ortac wrote:

You say “even a car” as if they are less reliable than our aero engines

“Even in a car where a failure will not cost lives” is what I meant…

Surely the big engine makers have been playing with this for decades and are on top of it. Still good to see a creative boutique shop like Koenigsegg make a public move.

It must be really hard because if you look how the camshafts on a latest generation VW engine work with variable valve timing and variable valve lift, it’s clear that independently actuated valves would be 100x simpler and cheaper but apparently not possible today.

Fascinating video!

I wonder if there is any data out there on the reliability of mechanical parts versus electronics. Having been in electronics since the 1970s it would not surprise me if metal bits are about 1000x more reliable.

pneumatically operated.

I wonder what those solenoids are doing?