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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.

Nissan recalling 909k vehicles globally over accelerator issue

Nissan is issuing a massive recall that will see the Japanese automaker repair 908,900 vehicles worldwide, with nearly 100,000 of the affected models in the United States. While an official recall notice from Nissan or the National Highway Traffic Safety Administration is not yet available, Reuters has been able to confirm the recall with Nissan.
Nissan's recall is kind of the opposite of the Toyota unintended acceleration, in that it covers a lack of acceleration. According to the report, a sensor in the gas pedal can develop faults, leading to a sluggish acceleration or an outright stall regardless of how much throttle the driver dials in. The huge recall covers mostly Japanese domestic models like the Serena, X-Trail, Lafesta and Fuga, which make up for 764,800 of the 908,900 faulty vehicles. However, 98,300 Infiniti M sedans are being recalled in the US, although it's unclear at this time which model years and trims are affected. The remaining vehicles are found in Europe and Oceania, according to Nissan spokesman Chris Keefe.
No injuries or accidents have been reported due to the faults. The 90-minute repair will see techs replace the accelerator pedal and tweak the engine control programs. We'll update this story as soon as Nissan or NHTSA makes an official statement.

Renault to Nissan: Stop trying to contact our board members

TOKYO/PARIS — Renault told alliance partner Nissan to stop contacting the French company's directors ahead of a Thursday board meeting as the Japanese automaker tried to share evidence of wrongdoing by its ousted chairman, Carlos Ghosn, two sources said. Ever since Ghosn's Nov. 19 arrest in Japan, Renault and the French government, the automaker's biggest shareholder, have demanded to see the findings of a Nissan internal investigation that include allegations of financial misconduct by the 64-year-old executive. Ghosn was charged on Monday in Japan for failing to declare deferred income he had agreed to receive for the five years ending March 2015. While Nissan fired him as chairman days after his arrest, he remains chairman and CEO of its French partner. Renault's board meets on Dec. 13, and the findings of Nissan's investigation will be shared at the meeting where Ghosn's future could be also debated, one of the sources with knowledge of the matter said. The French firm told Nissan not to contact its directors ahead of the meeting, because such contact was outside the agreed channels for communication of the sensitive findings, the source said. Nissan offered last week to brief Renault's board about findings on what it considers proof of wrongdoing by Ghosn, said a second source who has knowledge of the matter but declined to be identified as it was confidential. But Renault advised Nissan to brief its lawyers instead, which led to a meeting between the Japanese firm's officials and Renault's legal teams early this week in Paris, the person said. The Japanese automaker later invited Thierry Bollore, who was named Renault's deputy CEO with the same powers as Ghosn a day after his arrest, as well as board members, to examine the contents of the findings, said the source. Bollore, though, told Nissan on Tuesday to "refrain from contacting the board," the source said. The exchange between Renault and Nissan is another example of the testy relationship between the two automakers, despite assurances by executives on both sides to preserve the alliance. The alliance, of which Ghosn has been the driving force, is widely seen as vital for the members' long-term survival. Board members invited to see the evidence included Martin Vial, who heads the French state shareholdings agency, interim Chairman Philippe Lagayette and independent director Patrick Thomas, the second source said. A Renault spokesperson declined to comment.