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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.

Race recap: 2015 Singapore Grand Prix full of odd sideshows

What greeted the Formula One teams in Singapore? Confusion. The haze was so thick that observers wondered if the race would be held at all. Then practices began, and Mercedes-AMG Petronas driver Nico Rosberg took the first one, but the team fell away after that. Mercedes said it couldn't get the tires turned on, but no one believed the Silver Arrows was in genuine trouble. Then qualifying set the confusion in stone. Ferrari driver Sebastian Vettel laid down the best time in Q3, taking the team's first pole position since Germany in 2012. Daniel Ricciardo got his Infiniti Red Bull Racing into second, about one tenth behind Vettel. (That may make the team feel better after Ricciardo publicly asked for a better engine than the current Renault unit, and team advisor Helmut Marko said the outfit will quit F1 at the end of this year if it can't get a stronger powerplant for 2016.) Kimi Raikkonen put the second Ferrari in third, Daniil Kvyat put the second Red Bull in fourth. And only then came the Meredes'. Lewis Hamilton's best got him fifth, the Brit saying, "We don't really know what we have got wrong. For some reason the tires are not working on the car. We do the warm-up the same as everyone else and then you see someone one second up the road." For added emphasis on the reversal of fortune, his time was 1.6 seconds behind Vettel's. Teammate Rosberg is next to him in sixth, a further half a second back. Williams is still a hurting a bit on slow tracks, so Valtteri Bottas could only get into seventh ahead of Max Verstappen in the Toro Rosso and teammate Felipe Massa in ninth. When the red lights went out, the 2015 Singapore Grand Prix would get both less interesting and more interesting all the way to the final lap. The men up front got good getaways, and the order into Turn 1 was Vettel, Ricciardo, and Raikkonen. The race finished with those three in that order, never having conceded position. Vettel's Ferrari enjoyed the track so much that he laid a second per lap into Ricciardo for the first five, then relaxed. He'd let the gap come down later in the race a couple of times, but any time he wanted to see what his mirrors looked like without anyone in them he'd take off again. Rosberg took fourth position after holding down sixth for the first stint. It looked like he'd have an even worse day - for a Mercedes driver - when he had problems getting his car started and onto the grid before the race.

Analyzing De Nyscchen's 25-year comeback plan for Infiniti

"It took us 25 years to bring Audi back in the US. This kind of thing takes a long time."
When Johan De Nysschen left his post at Audi of America last year to take the seemingly thankless job of leading Infiniti's global operations, it seemed like a familiar scenario. Like Michael Dukakis going from one of two men that could have won the White House to teaching political science at an obscure Florida college.