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Infiniti spruces up the Q50 for 2018

Though overshadowed by the literally larger QX80 Monograph SUV concept, Infiniti's revised 2018 Q50 still made an appearance at the stand in New York. It joins a long list of cars including the Acura TLX, Hyundai Sonata, Mitsubishi Outlander Sport, VW Golf, and Toyota Sienna and Yaris that all went under the knife for the show. The Infiniti Q50's update may be one of the most mild, though, as it only consisted of cosmetic changes. Up front, the grille has been enlarged and given more prominent swoops at each corner. On the S version, sharp creases appear on either side of the primary grille and descend down to the lower, center grille. The outboard grilles of the front bumper have changed shape, too, and they now feature contrasting black plastic trim. The standard Q50 has a new bumper, as well, and though less aggressive than the S version, it still looks sporty with a more pronounced chin spoiler. Both iterations of the 2018 Q50 share the same tail end. The main change is in the rear bumper. A center diffuser has now appeared at the base. The contour of the diffuser is echoed by two creases in the bumper at progressively higher points. On the S model, the panel between the diffuser and the first crease is painted black, and the diffuser is painted in the body color. The standard model's entire bumper is painted in body color, and the diffuser looks to be a more muted black or gray. Inside, even fewer changes have been made. A new steering wheel with reshaped thumb grips is now included. Infiniti also added new stitching to the instrument panel cover and leather shift knob. You'll be able to examine all of these changes up close at an Infiniti dealer this summer when the cars arrive. Related Video: This content is hosted by a third party. To view it, please update your privacy preferences. Manage Settings.

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 Q50S getting G37's hydraulic steering for 2016

Sometimes, new technology doesn't make things better. Take the march of power steering technology as an example. Electrically assisted systems are in vogue at the moment for their ability to increase fuel efficiency, but tuning them to offer good feedback remains something of a dark art. Some automakers get it, but most don't. The previous hydraulically assisted setups just seem to be inherently more communicative when driven with enthusiasm. And it looks like Infiniti might be learning this lesson the hard way.
In talking with Keith St. Clair, the luxury brand's head of product planning, Car and Driver has learned that the Q50S is probably going to ditch its standard electrically assisted steering in favor of a hydraulic system derived from the old G37, a model soon to be renamed the Q40. The system should make the sedan more engaging behind the wheel, but it still won't help those who tick the option box for Infiniti's controversial Direct Adaptive Steering drive-by-wire system.
According to St. Clair, Infiniti's engineers have heard the complaints of critics and previous G37 owners about the Q50S model's electric steering system, and wanted to see what they could do. They didn't have to go far to figure it out - all it required was taking the steering rack off of a G37 and putting it onto the Q50S. After a little tweaking, "the car is a blast to drive," St. Clair reports. Now, the company is said to be fast-tracking the switch, and it could be ready for the 2016 model year.