Interesting motor concept, mainly for range extenders on a ev
INNengine's half-liter opposed-piston engine makes 120 horsepower in an ultra-compact, super-efficient package.
www.thedrive.com
~There's no cylinder head in this motor. Also no crankshaft, no camshaft, and no valves. That's why it's no surprise that this engine tips the scales at just 85 pounds. Somehow, it still produces 120 horsepower with just half a liter of displacement, thanks to what the company calls a single-stroke combustion cycle.