摘要 |
An engine includes a rotatable crankshaft. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft. An expansion piston is slidably received within an expansion cylinder and operatively connected to the crankshaft. A crossover passage interconnects the compression and expansion cylinders. The crossover passage includes a crossover expansion (XovrE) valve disposed therein. In an Engine Firing (EF) mode of the engine, the engine has a residual expansion ratio at XovrE valve closing of 10.0 to 1 or greater, and more preferably 15.7 to 1 or greater. |