waderoush writes: "Opposed-piston engines (with two pistons in the same cylinder) have been around since the 1920s, but have been used mainly in submarines and airplanes. Now several startups are working to make these high-efficiency engines practical for cars, trucks, and light vehicles — but they're under no illusions that Detroit will adopt the idea. Silicon Valley startup Pinnacle Engines, which is backed by the world's largest venture fund, is looking to a scooter manufacturer in India as its first partner. 'This ought to be music to Detroit’s ears, but to them I’m just some whacko in California,' says Monty Cleeves, Pinnacle's founder and CTO. 'This is Silicon Valley, and what does Silicon Valley know about making engines? Folks in Asia have almost zero ‘not-invented-here’ issues, whereas it’s pretty prevalent all over the U.S.'"