This prototype may look like a darkened Mazda3, but it's all new beneath the skin.
In addition to rocking an all-new, seventh-generation platform, the hatchback also features the new Skyactiv-X powerplant prototype.
The engine is unique in that it burns gasoline, but makes use of high-compression for combustion like a diesel.
Mazda's engine does use a precisely timed spark to aid in controlling the combustion.
To aid in creating the very lean conditions that the engine needs to operate efficiently, Mazda has equipped Skyactiv-X with a small supercharger.
Even the exhaust gas recirculation emissions system is temperature controlled.
An extremely high-pressure direct fuel injection system and in-cylinder pressure sensors are used to fine-tune the combustion cycle in realtime.
The prototypes feature very basic interiors with some areas covered by simple plastic shrouds.
Each example featured a small display on the dashboard that indicated what combustion the engine was operating in while we drove.
Illuminating different icons indicated whether the engine was using spark combustion, spark controlled compression ignition or running in a lean-burn mode.
In addition to leaning about the Mazda3's future, I was also able to visit with its great-great-great-grandpappy, the 1978 Mazda GLC.