1999 Mazda 626 Lx on 2040-cars

Auto blog

Mazda Skyactiv-X Review | The revolution begins with a squeeze-bang

The matte black Skyactiv-X prototype looks like a rough Mazda3, perhaps reconstructed after a bad wreck by an over-enthusiastic owner of a spot welder and lots of gaffers' tape. Ribbed ducts poke out of the dash sending two breaths of conditioned air to no one in particular. Even its revolutionary engine, the thing we're here to experience, is entombed in a massive, nondescript cover to mask its unseemly noises. It's a wild, strange way to meet a very unconventional vehicle that promises diesel-like fuel economy, a wide torque band, and an exotic method for burning less gas than ever before. It takes a few hours for Mazda's engineers to explain the fundamental principles of operation. For more detail, read our Skyactiv-X Spark Controlled Compression Ignition explainer, but here's a very brief overview. Skyactiv-X marries some traditional gasoline engine characteristics with a novel form of compression ignition called SPCCI. The key for Skyactiv-X is to use very high compression in the cylinder and an extremely lean fuel-air mixture. Squeezed right to the cusp of getting hot enough to blow up all on its own (which is very hard to predict), a squirt of extra gas and a spark interject to cross that compression-ignition threshold in a controlled and predictable manner. See the animation below: That takes a few essential components to get just right. One is a massive amount of computer processing power and some pressure sensors in the individual cylinders, because the ambient conditions change how and when these things happen. Skyactiv-X uses a clutched supercharger to pump in additional air when needed to nail the mixture precisely, and high-pressure injectors to get the low ratios of fuel to disperse properly in the chamber. And since it operates like a conventional gasoline engine sometimes, it uses valve timing to lower the very high compression ratio so it doesn't reach combustion ignition in that mode. In practice, the Skyactiv-X runs in compression ignition mode most of the time. In practical terms, that means it drives like a torquey gasoline Skyactiv engine. The torque curve is broad and flat — diesel-like in that respect. That also means it can get away with using a six-speed transmission and a lower final drive for better response. There's enough grunt and economy together that Mazda can let the engine spin faster — at 60 mph, it's running at roughly 1,000 more RPM than a similar gas engine, with greater efficiency.

Mazda MX-5 Miata goes Head 2 Head with Subaru BRZ

It's a battle that's been in the making for some time now: the Subaru BRZ versus the Mazda MX-5 Miata. And now that the new Miata has arrived – and in Club spec to boot – that's exactly what Motor Trend has lined up for its latest episode of Head 2 Head. Now before you go screaming that one's a coupe and the other a convertible, take a few commonalities into account. Roofs aside, both feature a 2.0-liter four mounted up front, driving the rear wheels through a six-speed manual transmission. Both are made by Japanese automakers and cost around $25-30k, give or take. Both produce around the same amount of torque, and while the Subaru may be more powerful, the Mazda's considerably lighter. To create a more even contest, then, you'd have to line a BRZ up against a Scion FR-S, or the MX-5 against the upcoming Fiat version of the same. Of course, being that close on paper doesn't mean that it's a draw. One has to come out on top. And after taking both along country roads and the Streets of Willow racing circuit, our friends at MT have picked one over the other. You'll want to watch the 22-minute video above (or at least skip ahead to the end) to see which came out on top, but if you're as enthused by a purist driver's car as we are, you'll enjoy every minute of it. News Source: Motor Trend via YouTube Mazda Subaru Convertible Coupe Economy Cars Performance Videos motor trend mazda mx-5 head 2 head

Mazda6 GX Grand-Am racer goes where no diesel sedan has gone before

There has never been a four-door diesel sedan in the Grand-Am series, until now: The blunt, bewinged grille of the Mazda6 GX has blown right through that wall. It's said that racing improves the breed, but usually the breed has gone on sale when the racing begins. One of the unusual aspects of the Mazda6 GX, on the other hand, is that while the diesel won't go on sale to the public until later this year, it will already have tasted racing blood by the end of the day. That kind of reversal is more likely found with super coupes like the Lexus LFA and Honda NSX.
Mazda has taken class wins at Daytona's 24-hour race a whopping 23 times since 1975, most recently in 2010 with the RX-8 in the GT class. This year the Hiroshima company decided to show off its SkyActiv technology, then turned things up to eleven by opting for its SkyActiv-D instead of the more conventional SkyActiv-G gas engine to run in the new GX class. It will be joined by competitors like the Lotus Evora and Porsche Cayman in the class, nevertheless, at 2.4 liters, it's the smallest engine on the grid.
Time has not been a friend, either - Mazda said that the first five SkyActiv-D engines off the production line went to Speed Source in Coral Springs, Florida, the company that preps Mazda's race vehicles. Still, race driver Jonathan Baumarito on the #70 car said that although the engine's been on the dyno since February of last year, it's only been in the car for about a month and there have been only a couple of test days.