Talk about a gee-whiz motor, TARDEC is showing off its Opposed Piston Opposed Cylinder Engine (OPOC) here at the 2008 SAE World Congress and we were impressed enough to take a couple of minutes to find out more. The engine is the result of a DARPA initiative to shrink the overall powertrain package in ground vehicle military applications. The horizontally opposed, twin bore four piston engine is an evolution of the shared bored opposed crank concept developed by the Nazis and swiped by the Russians for tank applications. This particular unit, while far from production ready, is capable of 320 HP, redlines around 3800 RPM. and tips the scales at only 380 lbs.


Everything here is pretty trick, the connecting rods are all titanium, there are two high pressure injectors per cylinder, and the system operates with a combined supercharger and turbocharger. Next time a Subie guy yammers on about how great their boxer motor is, talk to them about this baby.