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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.

2019 Infiniti QX60 and QX80 introduced with new Limited trim level

The 2019 Infiniti QX60 crossover and 2019 Infiniti QX80 full-size SUV debuted here at the New York Auto Show with new, more luxurious Limited trim levels. They include special wheels and even more luxurious interior touches. On the dark-grilled QX60 Limited, the custom wheels are 20 inches, and on the bigger QX80 they are 22. The half-leather seats on the QX60 are quilted, and the aniline color extends to the armrest and door cards as well. On the QX80, the "Limited" lettering stands out everywhere, from the center console to the seats, which are two-tone, leather and Alcantara. The QX80's dashboard wood trim is matte silver ash, and little trimline-specific details can be seen everywhere. The QX60's engine remains the standard specification 295-horsepower 3.5-liter V6, and the QX80's powerplant is the 5.6-liter V8 with 400 horsepower. Pricing hasn't yet been announced, but the QX60 Limited will be available this summer, and the QX80 Limited can be bought from summer onward. Related Video:

Infiniti releases first image of premium compact Q30 Concept

Behold, the Q30 Concept. Slated for a worldwide debut in Germany next month at the Frankfurt Motor Show, this concept previews a new entry-level premium compact that Infiniti hopes will attract younger buyers to the brand, as well as give it a competitor in a burgeoning new class that's quickly filling up with options.
What will set the Q30 apart? Aside from a bold and aggressive design that picks up where the new Q50 and many concepts have left off, Infiniti says the shape combines elements from three bodystyles, all of which appeal to the sort of buyer it's hoping snare. Can you guess which three? No peeking at the press release down below. Give yourself ten arbitrary points if your answer was coupe, crossover and hatchback.
Infiniti promises a ride height that will be high enough to earn crossover credentials, and we're guessing it's got an actual hatch back there, which leaves the coupe. Where's the coupe in the Q30's design? The influence of a two-door is a little more difficult to see with the naked eye, but what the Q30 shares with some four-door coupes on the market is a roofline that peaks and begins to slope back down before the B-pillar and rear set of doors.