Mazda Compression-Ignition Gasoline Engine Coming in 2018

Mazda Motor Corp. will introduce a compression-ignition gasoline engine at the end of next year that promises 30% better fuel economy than a conventional powerplant, The Nikkei says, without citing sources.

Media reports in mid-2015 said the engine would debut in a 2018 model, two years ahead of its original development schedule. Those reports said the engine would equal the efficiency of hybrid systems, but presumably at lower cost.

The concept is known as homogeneous charge compression ignition (HCCI). It functions like a diesel to ignite its air-fuel mixture through pressure rather than a spark plug. The technique, which can be applied to diesel and gasoline engines, causes ignition earlier in the compression cycle. This produces more uniform and lower-temperature combustion, resulting in greater thermal efficiency, less noise and lower emissions.

Developers, including Mazda, have experimented with HCCI for years. In 2011 the company described the technology as having a “high potential to become the ultimate form of internal combustion.” But achieving smooth operation over various engine loads has been a big challenge.

Mazda describes its solution as a second-generation engine for its family of Skyactiv technologies. The company plans to debut the technology in its next-generation Mazda3 small sport sedan, known in Japan as the Axela, when the car debuts at the end of 2018. The system will gradually be expanded to unspecified other models, according to The Nikkei.