While other manufacturers are downsizing engines and sticking turbos anywhere they’ll fit, Mazda has attempted to maintain a home for naturally aspirated motors — engines it believes should be sized appropriately for their intended application. On paper, this appears to be giving the competition an edge. Yet Mazda remains committed to offering the right tool for the job, introducing naturally aspirated Skyactiv engines with unusually high compression ratios. The latest, Skyactiv-X, combines spark-controlled gasoline combustion and compression-ignition diesel tech with a 24-volt mild-hybrid system.

The system delivers 178 horsepower and 164 lb-ft of torque in 2.0-liter guise, plus MPG improvements of up to 20 percent vs the old Skyactiv-G. But there’s a problem. With Mazda attempting to go upmarket, an economy-focused powertrain has to deliver in whatever region it’s sold, and introductory Skyactiv-X units are now viewed as too small for the United States. The result? The technology’s delayed arrival in North America, despite its deployment via the new 2.0 liter found in the 2020 Mazda 3 and CX-30 sold in Japan and Europe.  (Read More…)