According to Nikkei, a new SkyActiv family of engines is set to debut under the hood of the next-gen Mazda3 sometime in 2018 before making its way into other vehicles. In simple terms, an engine that uses HCCI burns the air/fuel mix using pressure instead of with spark plugs, just like a diesel. At 14:1, Mazda's gasoline engines already have some of the highest compression ratios out there, but a move to HCCI means cranking up the compression to 18:1.
While the tech sounds relatively straightforward, using HCCI means dealing with a number of side issues. It's one of those "on paper" ideas that compounds problems when put into practice. Heat, revs, and fuel must all be carefully managed as gasoline doesn't burn the same way as diesel. Mazda is mum on details, but the automaker seems confident that the issues have been sorted. If the new engines do indeed make it to market with HCCI, Mazda will have out-engineered GM, Daimler, and Hyundai, all of which have tried and failed to develop HCCI engines in a cost-effective package.
With the market moving towards electrification, it's interesting to see Mazda still focusing so heavily on traditional internal combustion gasoline engines. It's an indication of where they see the market heading for the next few years. Although the automaker has been hesitant to move forward with hybrid and electric powertrains, Nikkei also reports that Mazda will begin mass production of EVs in 2019.