Mazda's 2.5L turbocharged inline four-cylinder engine won a Ward's Auto 10 Best Engines award in 2017 for the CX-9. The engine is now also used in the 2018 Mazda 6. The engine produces 227 horsepower on regular gas, and 310 lb-ft of torque. It has a unique approach for downsized turbo engines, which generally result in good fuel economy at low loads, but fail to provide efficiency when the driver demands more power.
Several of the clever technologies within this engine include a 4-3-1 exhaust that maximizes exhaust scavenging for turbocharged engines, while also providing two separate airflow paths to keep the turbo spooled at both low and high RPM. The engine also has cooled EGR to increase the load at which a stoichiometric air fuel ratio can be used. Check out the video for full details about how this engine provides loads of torque, but still offers good fuel economy.