Mazda’s Lean Burn Motor Could Extend ICE Age

Mazda will stage the European debut next month of the first of its models boasting a gasoline engine to boost ICE technology’s climate control credentials.
While acknowledging that EVs are making inroads into future powertrain strategies, the carmaker is confident that ICE solutions have still a long road to travel before obsolescence. The latest combustion technology is featured in Mazda’s SkyActiv engine technology featuring in the new Mazda 3 hatchback it will be showcasing at the Geneva Motor Show.
This car will be powered by a gasoline motor with the carmaker’s Spark Plug Controlled Compression Ignition (SPCCI) claiming the high-revving performance of a gasoline with the low rev torque of a diesel. Yet, the main driver of the technology is to achieve fuel mixture two-to-three times leaner than today’s engines and, thereby, radically reduce climate changing emissions.
Mazda has released little more about the new car but in its published details of the SPCCI system it has been proven on a 2.0-liter gasoline engine. The technology manages to combine both spark plug and compression ignition in a bid to maintain very lean ratios of fuel in the combustion chamber.
SPCCI operates with compression ratios up to 16:1, still below the level required for compression ignition. At the right time, a small injection of atomized fuel directly around the spark plug builds a richer core. When ignited, this core creates a pressure wave spreading through the chamber, increasing compression and temperature to the point where the main body of fuel can combust by itself.
In this way the engine runs leaner through low rev ranges and uses less fuel producing fewer emissions. Conventional combustion is used only at high engine loads and during very cold starts. Mazda claims the engine can run more than 80% of time in a very efficient mode improving fuel economy by up to 30%. The engine also has Mazda’s intelligent new M Hybrid system, improving fuel economy and emissions.
The carmaker will also unveil a new compact SUV and Mazda’s MX-5 30th Anniversary Edition will also make its European debut celebrating three decades since its world premiere at the 1989 Chicago Motor Show. Also appearing at the show is the all-new Mazda3 hatchback and saloon, the first of the new generation of Mazda cars. This is the first production car to feature Mazda’s innovative SPCCI technology, which delivers superior initial response, powerful, linear torque and free-revving performance.
— Paul Myles is a seasoned automotive journalist based in London. Follow him on Twitter @Paulmyles_