2002 Nissan Xterra Xe - 2wd - Cloth - Automatic - Cd Player - A/c ( Hc977x ) 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.

Williams developing hybrid system for next Nissan GT-R?

Back in June, Nissan announced a new partnership with Williams that would see the Formula One team's applied sciences division help develop a new line of Nismo performance models. It's not the only agreement Renault-Nissan has signed with an F1 team: Infiniti is the title sponsor for Red Bull and Renault powers four teams on the grid. It's also just the latest client Williams has signed a deal with to apply the lessons it has gleaned on the F1 circuit to other racing and sportscars. But now we've got some more info on how Williams and Nismo intend to collaborate on the next-generation GT-R.
According to Australia's Carsales, Williams Advanced Engineering is developing the hybrid powertrain that will boost the next iteration of the supercar-slayer known as Godzilla. Which may seem strange considering that the Renault-Nissan Alliance has plenty of experience with electric propulsion on its own, but then Williams has proven itself something of a leader in the field of performance hybrid powertrains: it supplies them to Porsche and Audi for their Le Mans racecars, and to Jaguar for the C-X75 concept.
Whether Williams and Nismo will settle on a flywheel-based energy recovery system or a more conventional battery-powered system remains to be seen, but brakeforce regeneration likely won't be the only element that Williams will develop for the next GT-R. Expect its expertise in aerodynamics and composites to come to bear as well, which can only mean good things for the replacement for a sportscar that's already one of the most capable on the road.

Auditor had questioned Nissan on payments in Ghosn scandal, source says

TOKYO — Nissan's auditor had repeatedly questioned transactions at the heart of allegations of financial misconduct by former chief Carlos Ghosn, but Nissan said they were proper, a person with direct knowledge of the matter said on Wednesday. Ernst & Young ShinNihon LLC questioned Nissan's management several times, chiefly around 2013, about purchases of overseas luxury homes for Ghosn's personal use and of stock-appreciation rights that were conferred on him. But the Japanese automaker said the transactions and financial reporting were appropriate, the source told Reuters on condition of anonymity. The revelation shows Nissan and its auditor were discussing the transactions, in apparent contrast with Nissan's contention that the alleged misreporting of benefits for Ghosn was masterminded by Ghosn and a key lieutenant. A spokesman for EY ShinNihon, the Japanese affiliate of global accounting firm Ernst & Young, said he could not comment on specific cases. A Nissan spokesman declined to comment. Ghosn was arrested on Nov. 19 as he arrived in Japan. Prosecutors accuse him of falsifying Nissan's annual reports to understate by about half his total compensation of some 10 billion yen ($90 million) over several years. The high-profile former executive has denied the allegations, according to Japanese media. Ghosn remains in custody and is unable to speak publicly. He is represented by former prosecutor Motonari Otsuru, according to Japanese media. Otsuru's law firm declined to comment on Wednesday, and Otsuru has not responded to requests for comment. Nissan has largely pinned the blame on Ghosn and Greg Kelly, a former representative director who was arrested along with Ghosn on the same allegations. "As a result of the investigation, we are certain these two are the masterminds," CEO Hiroto Saikawa told a news conference on Nov. 19, referring to Ghosn and Kelly. He declined to say whether others at Nissan were involved in the alleged wrongdoing. An internal investigation is ongoing, and Nissan says it is cooperating with prosecutors. Nissan and Mitsubishi Motors have removed Ghosn as chairman in the wake of his arrest. The French member of the three-firm alliance, Renault, retains him as chairman and CEO.