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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 wants an American driver for its Le Mans team

"We'll use every driver development tool we have to take them to the next level, but they will also have to step up." - Darren Cox
Nissan is aiming to put an American behind the wheel of one of its LMP1 racecars in 2016 as part of plans to grow its motorsports program in the United States.

Nissan bringing 2014 Versa Note to Detroit

Nissan today confirmed that it will be showing the 2014 Versa Note - not Versa, not Note, but Versa Note - at next week's 2013 Detroit Auto Show. And while we can't see a whole lot from this one teaser image, we're willing to bet that the car looks a lot like this.
All Nissan will tell us at this time is that the Versa Note will have "segment-exclusive technology, outstanding fuel economy, smart packaging and class-leading cargo space." Sounds... class-competitive.
Given how turned-off we are by the second-generation Versa sedan, it'll be interesting to see just what's in store for this Notably more functional version of the affordable compact. Stay tuned for the full details live from Cobo Hall in just a few days, and scroll down to read Nissan's brief press blast.