The heart of the 2011 Mazda MX-5 remains a highly-responsive MZR-series 2.0-liter powerplant making 167-horsepower (158 for automatic transmission-equipped models). The MZR is light and compact, featuring chain-driven double overhead camshafts, a lightweight flywheel, variable intake valve timing, electronically controlled port fuel injection and coil-on-plug ignition. The sophisticated 2.0-liter four-cylinder engine gives strong performance, has