2004 Nissan 350z Enthusiast Coupe 2-door 3.5l 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 recalling 2012-14 Frontier pickups over fire risk

Nissan is recalling its Frontier pickup over fire concerns, according to a National Highway Traffic Safety Administration bulletin. A total of 13,535 vehicles are being recalled, all from the 2012 to 2014 model years, built between November 28, 2012 and December 27, 2013.
The NHTSA report states that "in the affected vehicles, a circuit breaker may have been installed incorrectly causing the main wire harness connected to the circuit breaker to face outward, potentially contacting a metal bolt located on the A-pillar." If this happens, it's possible that "the bolt may wear though the wire harness covering, resulting in an electrical short," NHTSA states. In the event of an electric short, a fire may occur.
The official recall will begin in March, where Nissan dealers will inspect the circuit breaker for the correct orientation, and if necessary, repair the vehicles, free of charge. Scroll down for the full NHTSA bulletin.

Nissan working on unspecified improvements to Carwings in Leaf EV

Fly a little higher, Carwings. Nissan has been using the communication system as a way for drivers of the battery-electric Leaf to do things like use a smartphone start the charging process remotely, check the charging status or find nearby charging stations. The service was one of the tools Nissan was offering to newbie drivers of the first US mass-produced electric vehicle to better familiarize themselves with ideas like recharging your car from miles away. Now, three-plus years into the model's lifetime, Nissan is looking to get more out of Carwings, Wards Auto says, citing Nissan North America executive Robyn Williams. Specifically, Nissan is hoping Carwings will eventually be able to communicate information about the battery's health, or lack thereof (i.e. degradation) to the driver. That issue was made clear a couple of years ago when Leaf drivers in hot-weather locales such as Arizona said their batteries were losing capacity at a faster rate than advertised. Nissan North America spokesman Brian Brockman, in an e-mail to AutoblogGreen, would only say that the automaker "is always working to determine ways to offer more value to customers via telematics systems like Carwings," but declined to be more specific about any particular technological advancements. Nissan debuted Carwings in late 2010, and, among other things, the concept was novel because it let Leaf drivers compare driving efficiency with other Leaf drivers (think of it as a real silent hypermiling contest). The feature had been used as a telecommunications system on a number of Nissan models in Japan for years before being introduced on the Leaf.