2012 Nissan Armada 2wd 4dr Platinum on 2040-cars

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Infiniti's new VC-T changes the rules of small turbocharged engines

The upcoming Infiniti QX50 crossover does not get our pulse racing, no matter how shapely the QX Sport Inspiration concept that previews it may be. No midsize SUV does, to be fair. But it has something special under the hood – the world's first production variable-compression-ratio engine. That means the QX50's 2.0-liter turbo four, which makes 268 horsepower and 288 pound-feet of torque, will have up to 27 percent better fuel economy. Here's how it works. The trend of moving to smaller, turbocharged engines carries with it one big falsehood. Under low load when the turbo isn't needed, these engines are less efficient than an equivalent engine without a turbo because of the low compression ratio the turbo requires. That is, if you never need the extra power, you're wasting fuel. Turbocharged (and supercharged) engines use a lower compression ratio to prevent detonation. When you force extra air in a cylinder and mix it with fuel, it's more likely to prematurely go boom. Lowering the compression ratio prevents this problem, but it's less efficient. Infiniti's VC-T promises the best of both worlds, with a compression ratio that ranges from 8.0:1 for high-power turbo needs to a 14.0:1 ratio for fuel-sipping efficiency. At its heart the VC-T engine is a simple idea, but it's complicated to explain. Consider yourself warned. The photo below from Infiniti serves as a good visual overview. For the truly nerdy, this patent application covers the mechanical concept. Instead of having the pistons connected to the crankshaft, Infiniti's engine has a pivot arm with a connection on each end. One end connects to the piston, the other connects to a second lower shaft, which is controlled by an actuator arm. At any given time the engine's pistons move up and down according to the lobes on the crankshaft. But the actuator arm can change the angle of the pivot arm up and down. That is, the pistons still move in the same motion with the same stroke, but phase the entire stroke up or down. Move the pivot up and there's less room at the top, which means a higher compression ratio. Move the pivot down and the compression ratio goes down, too. As an added bonus, the lower shaft eliminates the need for counter-rotating balance shafts. Infiniti says this system works constantly and can vary the compression ratio to any number between 8:1 and 14:1. It also uses electronic variable valve timing on the intake valves to switch into Atkinson-cycle combustion for greater efficiency.

A realistic approach to fixing Mitsubishi

There are going to be a lot of words written about what Nissan needs to do with Mitsubishi in the coming months and years in the interest of turning the brand around. After Nissan's purchase of a controlling stake in the diamond star brand, there's been more interest in Mitsubishi thanks to the potential of platform sharing and plenty of cash from Nissan-Renault to get the juices flowing again. But, while some have been doing their best to advocate for the return of the 3000GT, Evolution, and even the Starion - Many of these posts forget the reality of the market we live in today. As much as we like to look back fondly at the sports coupes of the '90s, a byproduct of the insane cash flows all the Japanese manufacturers had at the time, the reality of today puts a much greater emphasis on what is most-boring; Crossover SUVs, alongside mid-size and compact sedans. We do need to ask a fundamental question, how much Mitsubishi is enough to be able to continue to call the cars Mitsubishis? Aside from slight product revisions and reconfigurations, Mitsubishi (at least in North America) has been largely dependent on the same GS platform and 4B1 engines that date back to their long-time partnership with Chrysler (and Hyundai) in the mid '00s. Admittedly, the chassis and engines have served the company well, underpinning a wide variety of vehicles sold around the world, and seeing quite a few revisions to at least attempt to keep products competitive. But, the GS chassis is old, heavy, and severely out of date - and when matched to the underpowered 4B1 series engines - make for largely uncompetitive offerings in the market. While something like the Outlander Sport is indeed interesting compared to a Honda CR-V, it is by no means the smart choice in the segment. So, going forward, unless Mitsubishi has had a skunkworks of sorts developing their chassis and engine replacements over the past few years, what exactly are they planning to do for their bread-and-butter models? I think the straightforward answer is without a doubt the Nissan North America parts bin. With so many of their models selling well, and for the most part, are reasonably well-reviewed, it would be quite simple to adapt the chassis and powertrain to Mitsubishi's liking to create a high-volume alternative to what is currently available now.

Ford GT Mk II at Goodwood, Bentley EXP 100 GT concept EV and driving the Hyundai Veloster N | Autoblog Podcast #588

In this week's Autoblog Podcast, Editor-in-Chief Greg Migliore is joined by Consumer Editor Jeremy Korzeniewski and Associate Editor Joel Stocksdale. To kick things off, they talk about driving the Porsche Cayenne S, Hyundai Veloster N and Nissan Armada. Then they recap the Goodwood Festival of Speed, including the Ford GT Mk II that debuted there. Next up is news: the Bentley EXP 100 GT electric concept car, Ford canceling diesel for the Transit Connect and Elon Musk dismissing talk of a refresh for the Model S and Model X. Finally, they take to Reddit to help pick between a 2016 Audi S3 and a 2017 Alfa Romeo Giulia. Autoblog Podcast #588 Get The Podcast iTunes – Subscribe to the Autoblog Podcast in iTunes RSS – Add the Autoblog Podcast feed to your RSS aggregator MP3 – Download the MP3 directly Rundown Cars we're driving: 2019 Porsche Cayenne S 2020 Hyundai Veloster N 2019 Nissan Armada Ford GT Mk II debuts at Goodwood, and other impressions from the event Bentley unveils EXP 100 GT electric concept car Ford cancels diesel engine for Transit Connect Tesla Model S and X wonÂ’t get a refresh Spend My Money: Audi or Alfa? Feedback Email – Podcast@Autoblog.com Review the show on iTunes Related Video: