2015 Nissan Gt-r Premium 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 hopes to inject some spice into Rogue with 'Open The Briefcase'

Nissan is in the midst of rolling out the redesigned 2014 Rogue and has launched an interesting social media game called Open The Briefcase. The video that launches this game depicts a simple ride-share gone very wrong, with a man getting embroiled in a high-speed chase in a bid to escape with a strange briefcase. Eventually, it all goes haywire, and the man and his driver are captured. The only question seems to be, what's in the briefcase?
The contest, which asks participants to select one of three briefcases by cracking a code, is set to reward three individuals with a new Rogue. New attempts can be made each day, and participants can get additional chances to open a briefcase by sharing the video. The contest kicked off on January 3 and will run until February 14. Hop over to the contest page on Facebook to take part, or just watch the video below and enjoy a bit of entertainment.

2013 Nissan GT-R and 2013 Alpina B6 mix it up on track and street

Here we have Autocar making an unforeseen comparison: the Nissan GT-R against the Alpina B6 at Brands Hatch and on public roads. Steve Sutcliffe clobbers the circuit in the 3,828-pound, all-wheel-drive sports car, then sees how well the 4,114-pound, rear-wheel drive grand tourer does against it.
Sutcliffe says there are quite a few similarities between the two cars, but that's really only on the spec sheet. The Nissan's got two turbos attached to its 3.8-liter V6, 542 horsepower and 465 pound-feet of torque. The Alpina's got two turbos attached to its 4.4-liter V8, 532 hp and 528 lb-ft. But one's brief is to be a monster on the track, the other on the boulevard, and if there's anything the video demonstrates, it's each car's focus.