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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.

Survey says $25k barrier is a problem for EVs

The majority of consumers are more or less priced out of the market.
Electric cars are gaining popularity with the general public, but are they still too expensive? According to a survey 1,084 consumers by Navigant Research, a consulting firm located in Boulder, CO, 71 percent want their next car to cost under $25,000, while 41 percent won't go a cent above $20K. Looks like people are even thriftier than we'd originally thought.

Nissan edges out Tesla for most ZEV credits sold in California

When it comes to California zero-emissions vehicle (ZEV) credits last year, Nissan was selling and Mercedes-Benz was buying. The California Air Resources Board (CARB) put out its ZEV-credits numbers for the year that ended September 30, which is why we now know that Nissan, maker of the battery-electric Leaf, transferred 663.6 ZEV credits out of its account last year. That just edged out the 650.195 credits that Tesla sold. Chrysler's Fiat affiliate was a distant third, but its limited-production Fiat 500E was still able to generate some ZEV credits and then transfer out 235.2 of them. We don't know how much the buyers paid for these credits, since those details are kept private. It's an ever-changing rulebook over at CARB, anyway. On the flip side, Mercedes-Benz had to buy 663.6 ZEV credits in order to comply with clean vehicle-sales mandates in the most populous US state, indicative of the German automaker's gas-guzzling tendencies. Honda has cars that get better fuel economy than your average Benz, but its plug-in vehicles represent just a fraction of total sales and so it had to shell out for 542.5 ZEV credits. Chrysler-Fiat basically tread water, since the 237.8 ZEV credits it required for compliance canceled out gains on the other side of the ledger. Those Dodge Ram pickup trucks don't exactly help matters. Last year, Tesla sold the most ZEV credits while GM purchased the most. Overall, Californians bought about 3.5 million vehicles for the year that ended September 30, including 38,000 battery-electric vehicles, 30,000 plug-in hybrids and 570,000 conventional hybrids. The longstanding ZEV program means that California now has more than 100,000 ZEVs on its roads. Read this for more details on ZEV credit transfers in California. Featured Gallery 2013 Nissan Leaf View 55 Photos News Source: California Air Resources Board via Green Car Congress Government/Legal Green Mercedes-Benz Nissan Tesla Electric California zev credits