Mazda’s Skyactiv-Z Will Be ‘The Ideal Internal Combustion Engine’

These days, we rarely get to talk about a newly developed engine. Automakers prefer to hype up their future EVs, while internal combustion engines become little more than a footnote in press releases. Although that’s increasingly the norm, some companies are bucking the trend. Mazda defied the downsizing agenda with its gas and diesel inline-sixes, and now it’s working on what it claims will be the “ideal internal combustion engine.”

Originally announced last November, Skyactiv-Z is making the headlines once again. The first production model to utilize the all-new engine will be the next-generation CX-5. Mazda’s revamped SUV will arrive in late 2027 with an inline-four 2.5-liter gasoline engine and a hybrid setup developed in-house. The four-pot is being developed to meet future Euro 7 regulations in Europe and LEV IV and Tier 4 emissions standards in North America.

Mazda claims the new powertrain delivers an “even higher thermal efficiency and an overwhelmingly wider range ” than existing Skyactiv-G and Skyactiv-X engines. Lessons learned while perfecting the combustion process will be applied to the larger six-cylinder engines. Interestingly, the Japanese automaker also plans to use the newly gained know-how to improve rotary engines. A little over a year ago, the rotary engineering team was reinstated.

Although Skyactiv-X hasn’t been the roaring success Mazda had hoped, the plan is to “efficiently expand the area of SPCCI combustion.” The acronym stands for Spark Controlled Compression Ignition and “allows the engine to switch seamlessly between conventional spark ignition and compression ignition combustion by using a spark to trigger both types of combustion in different ways,” according to Mazda UK’s PR department. The intent is to deliver diesel-like fuel economy and initial power delivery with the high rpm and cleaner exhaust emissions associated with gas engines.

With Skyactiv-Z and new heat shielding technology, Mazda pledges to “reach the ultimate combustion threshold.” Lambda (“λ” in the Greek alphabet) represents the air-fuel equivalence ratio. Lambda (λ) is the air-fuel equivalence ratio. When λ equals 1.0, the air and fuel mixture is perfectly balanced during combustion. This optimal ratio maximizes efficiency and minimizes emissions by ensuring complete fuel combustion, therefore reducing harmful pollutants.

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Mazda

Mazda’s total engine variants will decrease by more than 50 percent following the arrival of Skyactiv-Z. Although the engine will run much cleaner, it won’t come at the expense of power. Tweaking existing engines to meet new regulations would’ve lowered output by as much as 30 percent, but Skyactiv-Z will comply with the stricter standards without losing power.

What about the rotary engine? It will be further developed as a range-extender, as seen in the MX-30 e-Skyactiv R-EV. While the crossover uses an 830-cc rotary engine as a generator, a more potent two-rotor setup is in the works for a US-bound vehicle. The beefier hardware has already been previewed in the gorgeous Iconic SP concept, which we’re still hoping will eventually see production day.