[Nathan Zachary]

Looks interesting, but I'm sure it has it's development curses. Durability is probably it's curse. Those lobes probably don't stand up to the high loads over the test of time. It probably has an upper limit as far as real drive shaft speed goes as well, about 2000 rpm, which is why they emphasize it's torque. At 2000 rpm the piston "pairs" have to fire 12,000 times with a tri lobed "cam". To build a valve train tough enough to maintain those operating speeds and be durable would be very expensive. It probably would make a better 2 stroke than a 4 stroke.
At any rate, the amount of hardening on high load surfaces, expensive metallurgy on a valve train, probably make it very expensive.
It would be interesting to see and hear one running though.

[Yardstick]

Good point. Each piston stroke only turns the crankshaft 1/3 of a revolution, so it'd take three times as many strokes to produce a given rpm. It's like it has a built in gear reduction. But couldn't you get around this by gearing it back up through the transmission?

[elbucko]

At any rate, the amount of hardening on high load surfaces, expensive metallurgy on a valve train, probably make it very expensive.

I agree. It seems to be a reinvention of the wheel.

It would be interesting to see and hear one running though.

Yes it would.

[Jack of all Trades]

You probably just hit a couple of nails squarely on the head. I work with very high pressure fuel pumps that look stikingly similar to this concept. Most of the working internals are superfinished tool steels or ceramic. Big bucks.

As RPM increases, the demands on the injectors, valvetrain and ignition system will increase at 3X the rate of a standard engine. Keeping everything moving, timed and controlled at high RPM is probably going top be difficult (read: expensive).