Sorry if this is a repost. I found this on Miata.net....it's an Australian company that designed and patented this new engine. Pretty cool design. It can produce 12-cylinder power with only 4 cylinders. Wonder if this will ever show up in cars we can buy.

http://www.revetec.com/website/index.html

How it works:

 

Also the Orbital engine was developed in Australia (Ralp Sarich).

Plus the best engine management computers and gearboxes come from Australia.

 

nice job. :thumbup

Only problem I see is that in addition to the bearing wear of crank engines, you'd have the additional friction wear on the spinning center eccentric (I think that's what you'd call it), and while there are undoubtedly advantages to be had, the drawbacks would be heavy, as well. Imagine using this in a F1 V8 It would be cool to fly around in an Indian sports car in the country using this kind of engine - sounds good in their vids (check the "Latest Update")

 

Interesting... seems to lose revs really quickly though... I think this would make more sense in a diesel application but nonetheless I'd love to see it in a production car.

 

The rotary meets pistons...

 

^^^
I would have to agree

 

Interesting design, I like it.

But Station, if you're trying to say that a 2 liter 4 cylinder of this type would have as much power as a 6 liter 12 cylinder of the normal type, that's not correct.

But if the design proves to be workable, what they're saying is that it'll provide better use of those 2 liters by applying max torque to the crank almost immediately after combustion. In a regular engine, the conrod applies max torque 60 degrees after TDC.

What I think is one of the coolest aspects of this engine is the fact that there are no cylinder wall forces from a conrod pushing a piston sideways. So given a proper valvetrain, high piston speeds should be possible, resulting in a combination of a long stroke high-torque configuration along with high rpms.

 

I read this in their FAQ:

A: A CCE engine can have from one to as many as eight cylinders. Each cylinder can fire 3 to 9+ times per rev. Three times is typically used in automotive. A four cylinder, four-stroke, trilobate cam produces six power strokes per rev. (12 cylinder four stroke equiv)

Maybe I misunderstood. Doesn't this mean it would produce the same power as a V12?

I agree...the benefit of no loads on the cylinder walls are huge. High rpm should be easy for this motor (at least the bottom end). I wonder how they grind cams though. Piston acceleration/deceleration would be so different from a conventional engine that cams with a normal profile don't work. The camlobes would have to be radically different to allow slower opening of the valves, thus avoiding piston contact. Would that reduce the engine's ability to breathe at high revs?

Also, how fast would the cams be spinning? If the engine redlined at a normal car's 6K (crankshaft), the pistons would be bouncing up and down three times per rev (18K ) and the cams would be half that speed at 9K, right?

Well, the bottom end looks like it could easily handle the revs, but I don't think the valvetrain would work that well at 9K. The F20C is rpm-limited by the top end, and at 9K the cams are spinning at "only" 4500. I think this will be a low-rpm motor. I love the design, though. It should have been done years ago.

 

What I am missing is exactly how it fires 3-9 times per rev.

The piston rises, the chamber fires, the piston goes down. Is that article saying it fires 3-9 times at the maximum length of the stroke? If so, what does this do for MPG?

It looks like this design, for now, would only work somewhat easily in boxer form. I wonder what an engine like this would sound like.

 

The shape of the crankshaft's lobes determine how many times each cylinder fires per crankshaft revolution. Details are on their site.

They also have video clips of it running on their website, if you want to hear it. Check it out!