Once the favored engine configuration for luxury and high-performance cars, the inline-six suffered a bit when the transverse (east-west) engine configuration became popular during the shift to front-wheel drive cars. The packaging benefits are obvious – no driveshaft or transmission intruding on passenger space or rear differential on cargo volume, plus turning the engine 90 degrees meant the front of the car could be shorter. But the inline-six is slowly, slowly crawling out of near-obsolescence, notably in Volvo, Jaguar-Land Rover, and Mercedes-Benz products. Add Mazda to that mix: An investor report first spotted by Jalopnik and confirmed by Mazda reveals that the company is developing a Skyactiv-X and Skyactiv-D inline-six that will be installed longitudinally (north-south) in a new "Large Architecture" platform.
Before reading any further, let's catch up on the Skyactiv-X and -D technologies. The former basically burns gasoline like diesel, providing some benefits and advantages of both types of combustion - here's an explainer on how that all works. We drove a prototype 2.0-liter Skyactiv-X 4-cylinder engine in a Mazda3 mule, too. And the Skyactiv-D series of engines is a comparatively typical turbodiesel. Mazda has a 2.2-liter turbodiesel inline-4 that has had a long and convoluted development and certification process, but is finally showing up in the 2019 CX-5.
As we noted our piece earlier today about the CX-5 diesel, we've been waiting for Mazda to bring its Skyactiv-D engines to market for years. Tripped up by an emissions certification nightmare that caused delays and resulted in lackluster power and fuel economy numbers, they're late to the party. In the CX-5 diesel, it's also a questionable proposition at almost $4,000 more than the much more powerful CX-5 Turbo. But today, Mazda's U.S. president confirmed to Autoblog that the diesel engine would make its way into the 6.
Like the CX-5, it'll only be offered with all-wheel drive and only on the top Signature trim level. Unlike the CX-5 diesel, which goes on sale in July, we don't know when the Skyactiv-D-powered 6 will go on sale. But it seems like later this year is a good bet. How much longer can Mazda wait, really, once the CX-5 diesel is on sale?
It seems like we've been waiting forever, but the wait is finally over. Mazda has finally launched a diesel version of the CX-5 for the U.S. market, unveiled at the 2019 New York International Auto Show. Specifically, the 2.2-liter Skyactiv-D turbo-diesel engine will be offered in the higher-end CX-5 Signature AWD, part of what Mazda calls its "path to premium," as the company continues to set its sights on some of the more expensive competition.
The Skyactiv-D 2.2 makes use of a sequential twin turbocharger that employs a smaller turbocharger first at low rpm for quick throttle response, after which a valve opens to spool up a larger turbocharger at higher rpm. Mazda says this provides "smooth and linear response from low to high engine speeds, and greatly increases low- and high-end torque." Mazda estimates the output of the engine to be 168 horsepower at 4,000 rpm and 290 pound-feet of torque from a low 2,000 rpm. The engine has a rev limit of 5,500 rpm.