And that's just one route. Another is the EcoMotors International (EM) opoc engine, aka open piston, opposed cylinder. Here's how it works. Instead of an I or a V pattern, EM's opoc is laid out ...

While most engines made in the last 100 years have adhered to the standard single-piston per-cylinder design, the TS3, also known as the "Commer Knocker," is an exception. The opposed-piston ...