The ND's 2.0 Skyactiv-G, engine code PE-VPS, is a high-compression, naturally aspirated, direct-injected four. Understanding it starts with the compression ratio: around 13:1, unusually high for a pump-gas engine.
Mazda makes that work with careful combustion-chamber design, a long 4-2-1 exhaust to reduce residual gas and knock, and precise direct fuel injection
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