2004 Nissan Titan Le King Cab 4x4 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.

So, how do you actually pronounce that automaker's name?

You probably have that friend who always says Porsche wrong, or maybe it's someone who keeps reminding you it's actually two syllables. Whichever side of the pronunciation debate you fall on, you'll find someone to root for in the video above. And before you ask, this was all the video team's idea. So don't get mad at me for being the voice of reason. BMW Chevrolet Hyundai Nissan Rolls-Royce Videos Original Video nissan qashqai

Nissan, Mahindra may bond over EVs

Like Lloyd in Dumb & Dumber rejoicing that he's got a "one out of a million" chance with Mary Swanson, electric-vehicle advocates in India can do the same. That's because both local automaker Mahindra and Japan-based Nissan say they would consider working together to promote EVs in that country. Executives with Nissan and Mahindra, which makes the Reva e2o EV, independently told Autocar Professional that they would consider collaborating with the other company in order to speed up plug-in vehicle adoption in India. Nissan, which already works with companies such as Honda, Mitsubishi and Toyota to various degrees, said this collaboration would most likely revolve around electric-vehicle charging infrastructure advancements, a move that obviously helps all plug-in vehicles. Of course, nothing official has been announced. Last March, the Mahindra Reva e2o, which costs the equivalent of about $11,000, went on sale in India, with the company estimating at the time that it could manufacture 30,000 of the electric vehicles each year. In February, Mahindra debuted two electric cars at the New Delhi Auto Show, including the Mahindra Reva Halo EV concept sports car and the Mahindra Racing Formula E electric race car. The following month, India's Financial Express reported that Mahindra was targeting Sri Lanka and Norway for e2o sales. That car has a 62-mile single-charge range and a top speed of about 60 miles per hour. Featured Gallery Mahindra Reva E2O News Source: Autocar Professional via Cartrade.comImage Credit: Copyright 2014 Gisli Gislason Green Nissan Electric mahindra collaboration