11 G25x-awd-22k-1owner-heated Seats-back-up Cam-leather-fog Lamps 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.

2013 Infiniti IPL G Convertible

Infiniti rolled out the IPL version of its G37 Convertible at the Los Angeles Auto Show more than a year ago. The Infiniti Performance Line treatment logically mirrors that of the IPL G Coupe, meaning it receives both cosmetic and mechanical tweaks designed to raise the pulse of driving enthusiasts. Aside from the overstated aerodynamic styling components and huge exhaust tips, the cabin features special leather upholstery, aluminum trim and IPL badging to distinguish it from lesser siblings. Under the hood, the 3.7-liter V6 (VQ37VHR) has been recalibrated to deliver 343 horsepower - 18 more than the standard coupe - and 273 pound-feet of torque. The suspension has been upgraded with firmer spring and stabilizer bar rates, multi-piston sport brakes are fitted and 19-inch graphite-finish wheels wrapped with summer rubber are bolted on. There are only two exterior color choices (Moonlight White and Malbec Black) and two upholstery choices (Stone and IPL-exclusive Monaco Red). Everything sounds marvelous until someone reveals its as-tested $62,415 window sticker.
DRIVING NOTES
The three-section steel roof raises and lowers in a leisurely manner - give it about 30 seconds each way. While it is marvel to watch, the operation seems clunky, not fluid. Buttoned up, with all four windows closed, the cabin is comfortable. Wind noise is minimal and the front buckets coddle passengers in all the right places. While tight, those of smaller stature will find the two rear seats tolerable for short journeys (my kids never complained). Outward visibility is also very good for a convertible - no impeding B-pillar.

Infiniti QX70 drops V8 for 2015, holds line on pricing

QX70 was the only application for the 5.0L, making it a tough sell in the boardroom.
It was always easy to chuckle a bit at Infiniti's branding of its FX crossover as a "bionic cheetah" - until you drove the thing. It was something of a revelation when it came on the market in late 2002 - certainly visually, but also in terms of performance, particularly in V8 guise. The Porsche Cayenne burst on the scene at the same time, and between the two of them, they vividly illustrated that the idea of a performance utility vehicle wasn't the oxymoron it first appeared to be.