Mazda Skyactiv 2 engines will save your fuel dollars

Mazda is already confounding convention with its Skyactiv technology, with the high-compression and naturally-aspirated (in petrol guise) engines contrasting with an almost industry-wide reduced-capacity, forced induction policy for cutting fuel consumption and emissions.

Despite Skyactiv’s demonstrated gains, a new report out of Europe suggests that the next generation of Skyactiv engines will improve efficiency by a further 30 per cent.

Automotive News reports that Mazda will introduce Skyactiv 2 engines in around 2020, and the new engines will focus on improved internal combustion.

"If we want to dramatically improve fuel economy from here, the only route is through lean burning,” Mazda’s powertrain boss Mitsuo Hitomi says.  
A key motivator for Skyactiv 2 is to meet new 95g/km European carbon dioxide emissions standards set for 2020, and 65g/km in 2025.

Mazda aims to achieve these improvements by raising the compression ratio of the petrol engines from an already industry best 14:1 to 18:1, and therefore producing the same combustion temperature (power) with a leaner fuel mix (less fuel). 

Such a combustion ratio will require significantly stronger engine construction and more precise ignition and fuel and air metering to deal with the more volatile combustion conditions.

This will be taken care of by homogeneous charge compression ignition (HCCI), which compresses the fuel and air to such a point that it self-ignites without needing spark – similar to the way a diesel engine works. HCCI also promises more complete fuel burn and lower nitrogen oxide (NOx) emissions.

Such efficiency gains could also help Mazda avoid investing in expensive CVT, dual-clutch, or transmissions with greater than six ratios like many rivals.

Skyactiv 2’s development is set to parallel Mazda’s work with stop/start systems and brake energy regeneration systems, along with its licencing of Toyota hybrid drivetrain systems as found in the new Mazda 3.

Beyond Skyactiv 2, the report suggests that Skyactiv 3 will focus on thermal efficiency to improve fuel consumption and emissions even further, and work toward a corporate goal to match pure-electric vehicles for well-to-wheel net carbon dioxide impact.

This reporter is on Twitter: @Mal_Flynn