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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's Nismo celebrates 30th year with video retrospective

Nismo, the motorsports and high-performance arm of Nissan, has a lot of racing success to celebrate in its history and possibly even bigger accomplishments to look forward to. The company is commemorating its 30th anniversary with a video looking back at its most important milestones from each year of its past.
Nismo's job first and foremost at its genesis was to excel at motorsports. It wasn't too long after the division was founded in 1984 that the company made its first of many attempts to take an overall victory in the 24 Hours of Le Mans. It never quite succeeded in that goal, but still managed to do well in long-distance competition elsewhere. At the same time, Nismo was racking up wins in touring car races in Japan.
Eventually, the division's engineers started dipping their toes into tuning road cars, in addition to going racing. What began as something sporadic has become a growing part of the Nissan lineup with Nismo-branded models of the 370Z, Juke, Note in Europe and the GT-R.

Renault planning a Tata Nano rival. Again.

Four years ago, Renault confirmed that it would partner with India's Bajaj Auto to develop a rival to the Tata Nano. At the time, as everyone waited for the Tata Nano to arrive, you could have used a Richter scale to measure the tremors the executive suites of any automaker with an interest in the low end of emerging markets. Then the Nano, still the cheapest car in the world, didn't sell so well - at the end of last year its sales were just six percent of its most conservative projections - and everyone seemed content to let Tata spend the money to figure out if there really was a market for the cheapest car in the world.
Renault believes there is, kind of. Automotive News Europe reports that it will partner with Nissan to build two low-priced cars for emerging markets, one for €3,000 ($3,888 U.S.) and another for €5,000 ($6,400 U.S.). The price of the least expensive offering is nearly $1,400 more than a Nano, which costs $2,500, and that can't be considered a small sum in comparison. But one of the hindsight knocks on the Nano has been that even in emerging markets buyers don't want a car whose biggest lure is that it is cheap; they'd rather give their aspirations a bit more of a workout.
Renault's offerings are scheduled to hit the non-Western market in late 2014, which is coincidentally the same year that will see the return of the budget-minded and emerging-market-specific Datsun nameplate. They'll be built in Renault facilities in Chennai, India, with no mention made of Bajaj this time around.