2011 Nissan Sentra 2.0 Sr on 2040-cars

Auto blog

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 Canada offers box-fresh racecar for $19,998 [w/video]

Nissan is seriously emphasizing its commitment to motorsports with projects like next year's GT-R LM endurance racer at Le Mans and the company's participation with GT Academy. At least in Canada, the automaker is adding another opportunity to get people onto the track with the new Nissan Micra Cup one-make race series. Sure, the Micra might not as quick as a GT-R, but this series offers Canadians a chance to start racing for a reasonable price. Nissan claims the events have "the lowest running cost of any Canadian series," and we can't think of a cheaper turnkey new racecar in all of North America.
The cars are all based on the not-for-US Micra 1.6 S M/T model with a 1.6-litre four-cylinder engine making 109 horsepower and 107 pound-feet of torque and a five-speed manual gearbox. The only real performance upgrades are a Nismo suspension kit, new exhaust, improved brake pads and sticky Pirelli tires. For added safety, the interior is entirely stripped out and is replaced with a full roll cage with a driver protection net, FIA-approved racing seat with five-point harness, fire extinguisher and front and rear tow hooks. The whole, race-ready package will set competitors back $19,998 Canadian dollars before taxes.
The inaugural Micra Cup series begins in May 2015, and the first season is exclusively taking place in Quebec, with the promise of moving to other provinces if it's a success. Each event includes a half hour of practice, a half hour of qualifying and a pair of half-hour races. Nissan is estimating impressive fields of over 25 cars of competitors.

Nissan Altima and Sentra to get Murano-inspired design redo

The Nissan Altima and Sentra sedans are both very competent, economical, comfortable and well-equipped ways of getting from A to B. They're also both decidedly boring to look at, which is not a good trait in their increasingly style-driven segments.
To rectify this, Nissan is planning design overhauls for its mainstream, with the Sentra adopting the sportier, Euro-style looks of the Pulsar, according to The Car Connection. While that (sadly) won't mean the five-door Pulsar will come to the US market, fitting the European stylings to the Sentra should go a long way towards broadening the car's appeal.
That parcel of information comes from Nissan design boss Shiro Nakamura, who spoke to The Car Connection at last week's Paris Motor Show.