This one is Mazda’s halo SPCCI (spark-controlled compression ignition) petrol engine that launched with the 3 back in 2019 ... and the unit can swap between spark ignition and compression ...

The 2.5-liter inline-4 that replaced the 2.3 is also a very good engine, and Eric says the only time he gets a request for those motors is when someone wants to swap one into a Mazda Miata.