2014 Nissan Altima 2.5 S 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.

Nissan IDx 'in the plan' for production, needs support from fans [w/poll]

If there's a trend in the auto industry we can firmly get behind, it's the small, light and affordable rear-drive coupe. The positive critical reception to the Scion FR-S and Subaru BRZ twins has encouraged other manufacturers to look at building their own rear drivers, and even a few to show actual concept cars based on the idea. The Chevrolet Code 130R from 2012 and more recently, the Nissan IDx twins that were first shown at the 2013 Tokyo Motor Show both come to mind, as does the brand-new Kia GT4 Stinger Concept.
Nissan trotted out the IDx Nismo and the IDx Freeflow for another showing in Detroit and we'll admit to being totally smitten with both cars. Again. The duo draw inspiration from the iconic Datsun 510, a lightweight, affordable rear-driver that remains a cult favorite decades after production ended.
Now, a report from our friends at AutoWeek reveals that we may, possibly, hopefully see a production IDx, provided fans make a strong enough case for it. "It's in the plan," Nissan product boss Andy Palmer told AW. According to the report, Palmer said the IDx is "into the first sage of the development process. The next stage is project validation and then looking at the business case. It's no one's intent to waste millions of the company's money, so obviously we have a good feeling about this one."

Nissan recalling more than 1M vehicles for airbags that may fail to deploy

Nissan and the National Highway Traffic Safety Administration have issued a recall for 989,701 vehicles in the US due to an issue with their passenger-side airbag systems. Affected Nissan models include the Altima, Leaf, Pathfinder and Sentra from the 2013 and 2014 model years, and 2013 NV200 taxis. Affected Infiniti models include the 2013 JX35 and 2014 Q50 and QX60 utility vehicles.
Reuters is reporting that a total of 1,053,479 vehicles are included in the recall globally, with about 60,000 of the affected vehicles having been sold in Canada.
The fault apparently lies in something called the occupant classification system, which may, in the recalled vehicles, incorrectly classify the passenger seat as empty when it is in fact occupied by an adult. When the system fails to recognize the passenger, the passenger-side airbag may deactivate, and could therefore fail to deploy in the event of a crash.