- customers in europe can now order the mazda 3 with mazda's skyactiv-x gas-powered spark-controlled compression ignition engine.
- the engine uses gasoline, but can switch between normal spark ignition and a novel form of compression ignition like as a diesel engine for greater efficiency.
- in addition to the impressive fuel consumption figures, mazda also released horsepower and torque specs for the euro-spec 3's skyactiv-x engine.
mazda is officially putting its advanced skyactiv-x gasoline engine on sale—at least in europe. the engine is coming to the u.s. market later. the automaker has also made available the first official specifications and fuel-economy data for the new engine, though they're only applicable to europe for now. until this point, we've had only estimates for the x's horsepower and torque from when we drove a mazda 3 with a prototype version of the engine, along with vague hints of big-time efficiency.
power and mpg numbers
so, here are the details: in 2.0-liter form, the europe-market skyactiv-x engine produces 178 horsepower at 6000 rpm and 165 pound-feet of torque at 3000 rpm. those figures are slightly lower than those of the u.s-market mazda 3's 2.5-liter four-cylinder, which makes 186 horsepower (also at 6000 rpm) and 186 lb-ft of torque (at a higher 4000 rpm). the sky-x engine has an incredibly high 16.3:1 compression ratio, though actual cylinder pressure varies.
most impressively, the mazda 3 equipped with the skyactiv-x 2.0-liter engine gets 50 mpg according to the optimistic nedc european combined test cycle. on that governing body's highway cycle, which benefits the compression-ignition setup even more, the thriftiest skyactiv-x-equipped mazda 3 scores 60 mpg. again, take these figures with a grain of salt—the epa test cycles will no doubt generate lower figures, but they're still expected to tower above the current mazda 3's highest epa estimates of 30 mpg combined and 36 mpg highway. plus, the euro x is backed up by a 24-volt mild-hybrid system that allows for extended engine-off periods when stopped in traffic or at stoplights.
at least overseas, skyactiv-x will require fuel equivalent to american mid-grade octane, though we've been told the engine can run on regular. it also can be paired with either the mazda 3's sedan or hatchback body styles, front- or all-wheel drive, and six-speed manual or automatic transmissions. that's a lot of choice, though we suspect the lineup will be narrower for american consumers when skyactiv-x makes it stateside later this year. for now, the order books are open for europeans, who can expect deliveries to begin this fall.
what is skyactiv-x?
several large automakers, including hyundai and daimler, have been on a quest for years to crack the compression-ignition gasoline engine code. they've all struggled to make the concept work over the wide range of engine speeds and with the responsiveness automotive applications require without violent engine knock and other issues.
mazda's solution is spark-controlled compression ignition, or spcci. for a full explainer on how this works, see our technical breakdown here. in brief, it allows for an ultra-lean air/fuel mixture, as in a diesel, the key to those big-time miles-per-gallon numbers. mazda's breakthrough on the technology was its decision to forgo full-time compression-ignition (the source of many a headache for mazda's competitors looking to develop the technology) operation. instead, for startup, hard acceleration, and high engine speeds, where scompression ignition of gasoline has proven difficult to manage, the skyactiv-x engine runs like a normal, spark-ignition engine.
for steady-state cruising, light acceleration, and moderate engine speeds (what we would consider light loads), the mazda engine switches to compression ignition. unlike its competitors, which have tried to run gasoline engines like diesels—without a throttle and using fuel injections in response to load requests—mazda never shuts off its spark plugs. instead, it uses them and a novel fuel-injection protocol to control engine loads. essentially, the plugs ignite a tiny, secondary droplet of fuel, and that combustion event in turn raises cylinder pressure enough to combust the larger, primary air/fuel mixture and initiate the power stroke.
cool stuff, right? you might need to wait for it, though. when reached for comment, mazda refused to offer a concrete timeline for the skyactiv-x engine reaching american consumers. previously, we'd been told the engine could come here as early as this year, likely as an option above the mazda 3's 2.5-liter four-cylinder gas engine.