Atkinson-Cycle 2.0-Liter 4-Cylinder Engine

What’s the Benefit?

Honda engineers update an established engine design with leading-edge technology to create an extremely fuel-efficient powerplant.

The Feature:

The Civic engine makes for excellent efficiency as well as responsive power output.

• Developed many decades ago, the original Atkinson-cycle engine improved fuel efficiency by reducing the volume of air and fuel introduced on the intake stroke and compressed on the compression stroke.  
• This smaller intake charge would then burn more efficiently during ignition, while still providing adequate torque on the power stroke.  
• For the Civic, Honda engineers used the flexibility of Variable Timing Control (VTC) on both camshafts to simulate the original Atkinson-cycle principles, with operating efficiency that goes far beyond a traditional internal-combustion engine.  
• Specifically, VTC delays the closing of the intake valves until much later than usual on the compression stroke.  
• The resulting smaller volume of air/fuel mixture then burns more completely and efficiently during the power stroke.  
• When needed, valve timing can be adjusted more like a conventional engine’s for greater power output. 
• Bottom line, the 2.0-liter Atkinson-cycle 4-cylinder engine is like having two engines in one.