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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.

Infiniti bringing Q50 Eau Rouge to Geneva, now with engine [w/video]

During last month's Detroit Auto Show, Infiniti rolled out the lustrous Q50 Moulin Eau Rouge concept - a preview of what could be a solid performance offering from Nissan's luxury arm. Problem is, the car shown in Detroit was all show and no go - literally.
Infiniti was keen to talk about how the Eau Rouge would feature "a big personality, V-cylinder engine with forced induction" with "over 500 horsepower and 600 pound-feet of torque," but the showcar had no such powerplant underhood. In fact, it didn't have any powerplant under the hood at all. That'll change next month, however, as Infiniti has now confirmed that it will bring the Q50 Eau Rouge to the Geneva Motor Show in March, complete with the promised "big personality" engine.
"Our engineers have perfectly captured the tone of Infiniti's take on premium performance, and a car that is as impressive as the Q50 Eau Rouge sounds is surely a car to challenge performance cars in the premium sector," said Infiniti's President, Johan de Nysschen. Regarding that sound: he ain't foolin' - the automaker has released a teaser video that gives us our first listen at what the Q50 Eau Rouge will sound like once its powerplant is nestled underhood. Scroll down to give it a watch - err, listen - and have a look beyond that for the company's official press blast.

Infiniti QX30 Concept teased ahead of Geneva reveal

Nearly a year and a half after Infiniti unveiled the first Q30 Concept at the 2013 Frankfurt Motor Show, the company is preparing to unveil a high-riding version of the concept, wearing the QX30 moniker, ahead of next month's Geneva Motor Show. While we've yet to receive any details on what to expect of the new QX30 Concept, Infiniti has issued a single teaser image of the car's shapely backside, revealing a pair of trapezoidal exhausts that have been integrated into the rear bumper. That bumper sits particularly high to accommodate what looks to be a small hatch with a prominent space between the slim ribbons of the LED taillights. Similarities to the Q30 hatch, meanwhile, are obvious. The taillights are similarly shaped, as is the tailgate and the integration of the dual exhausts (although they are shaped differently on the QX30). Of course, as soon as Infiniti bothers to release the full and complete details for its upcoming concept, we'll be sure to relay those on to you. Until then, have a peek at both the Q30 and the QX30 and let us know what you think in Comments. Infiniti gears up for premiere of QX30 Concept in Geneva Hong Kong – Infiniti will take the covers off the QX30 Concept at the Geneva International Motor Show next month. The QX30 Concept is the Infiniti design vision which will inspire a new premium compact crossover targeted at a new generation of premium customers. Set to be revealed at Infiniti's press conference, scheduled for 14:30 on 3 March in Geneva, the QX30 Concept aims to reignite the premium compact segment with a distinctive approach to design that looks beyond the practicality and conformity expected of the segment. The potential customers for such a concept are searching for a product to suit their 'urban week and get-away weekend' lifestyle and the QX30's compact footprint matches that. Combining the sleek lines of a coupe with the rugged looks and commanding seating position of a crossover, the QX30 Concept foreshadows an urban explorer which is equally at home in the city as it is on the open road.