Interesting engine

[Agent]

http://gas2.org/2008/06/26/low-cost-...-fuel-economy/

[kalniel]

That looks horrendously large.

[Agent]

Claims 50% smaller?

[Salazaar]

Looks like a brilliant idea. He's going to be a very rich man if he licenses it out properly.

[dave87]

I suppose its only an advancement of the Boxer type engine which BMW, Subaru and Porsche have been using, amongst others, for years.

I guess the clever part is because of its layout, it'll be able to provide more torque without the need for higher revs, hence being able to increase fuel efficiency.

[Zak33]

that is INSPIRED!!!!

[dave87]

Zak - from the animated gif (though I don't know whether it will be reflective of the true firing order) it seems they've gone down the route WSB/BSB inline 4s went - ie that of a Big Bang.

It seems 1 of each pair are firing at the same time, perhaps that is where the torque is coming from?

Or am I skipping the need for 2 revolutions for 4 stroke to complete its cycle?

[Lowe]

Would be a sod to work on though. Imagine trying to change the plugs!

[Zak33]

Or am I skipping the need for 2 revolutions for 4 stroke to complete its cycle?

yes, you are.

But the prnciple of the rotating cam with the rollers turning it is inspired.

[filbert]

yes, you are.

But the prnciple of the rotating cam with the rollers turning it is inspired.

If it's 4 stroke any idea how the valve train works? I can't work it out, there seems to be 2 cams at the top but I've no idea how they'd work.
Also it would sit very high in the engine bay with the output shaft so low.

[Rave]

So where is the 50% efficiency increase coming from? Is the combustion process somehow much more efficient? Because I don't believe for a second that a conventional engine loses 50% of its output power to drag on the crank.

By the looks of it, it's a typical science article, written by someone with very little idea of the actual science. Right after they say that it'll halve the fuel consumption of a typical small car, they link to this article:

http://www.revetec.com/news097.htm

....which states that they've actually achieved an efficiency of 38% with the engine, as against a typical efficiency of 32%. They did this by running the engine lean with 98RON fuel (and I'll bet no catalysts). Sorry, but that's just not the massive jump in efficiency the article portrays it to be.

I also have serious doubts of the ability of the engine to rev hard without destroying itself (most probably the roller bearings would go first?).

It is a clever idea, but it's not going to change the world if you ask me.

[badass]

Its only revving lower because the pistons are going up/down 3 times for every crank revolution. So 2000 RPM in this = 6000 Cycles/min for the pistons. In a normal 4 stroke, each crank revolution = 1 piston cycle.
Since the main thing limiting engine speed is the Valvetrain, then the next thing is the piston speed.
Its a good idea, but its not going to be anything special fuel efficiency wise.

[Vimeous]

Fascinating but wouldn't it be a pain to balance?