2009 Nissan Altima S Coupe 2-door 2.5l on 2040-cars

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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.

Mitsubishi, Nissan will build mini EV together

That minicar project that erstwhile competitors Nissan and Mitsubishi launched about four years ago is about to go a little more maxi. NMKV Co., the joint venture established in June 2011 by the two Japanese automakers to make minicars, is going to get more resources specifically to ease a move into the electric-vehicle sector. Specifically, Nissan, which makes the all-electric Leaf, is going to have a bigger role in the testing, design, and development of the partnership's mini EVs. A memorandum of understand between Nissan and Mitsubishi, maker of the i-MiEV, is in the works. So far, the joint-venture has sold about 500,000 gas-powered three-cylinder compact vehicles under the two automotive brands, so it must be doing something right. The first Nissan Dayz and the Mitsubishi eK Wagon models started production in 2013. Sales of the Nissan Dayz Roox and Mitsubishi eK Space, which went the higher-roof route, began early last year. Nissan and Mitsubishi started making noise about this last summer, when word came out that the little EV may be priced at less than $15,000 in Japan, quite a bit cheaper than either the Leaf or the i-MiEV over there. As with the current models, the future minicar variants will be produced at Mitsubishi's Mizushima factory in Japan. So far, the partnership would only say that details about NMKV's next-generation mini EV will be released "at a later time," so specifics like range and other performance measures will have to wait. Until then, you can take a look at NMKV's press release below. Nissan, Mitsubishi Motors and NMKV reach agreement on planning and development of next-generation minicars Nissan Motor Co., Ltd., Mitsubishi Motors Corporation, and their joint venture NMKV Co., Ltd. today reached an agreement to continue their joint project regarding development of the next generation of current minicar models. The three companies will soon sign a memorandum of understanding. The companies aim to develop more competitive products by optimizing resource allocation and their respective roles and responsibilities. Nissan will be more deeply involved in development operations, such as design development and testing. In addition to its product planning and project development roles, NMKV will strengthen its management capabilities by adding a new department to enhance collaboration with engineering and manufacturing functions. Vehicle production is planned to continue at Mitsubishi's Mizushima Plant.

Next Nissan GT-R to take cues from GT-R LM Nismo Le Mans entry

For those wondering why Nissan named its coming Le Mans Prototype the GT-R LM Nismo, colliding the two worlds of sports car and prototype racing, an article in Autocar might have the answer. The deeper union is explained by saying that the next-generation GT-R will use "hybrid technology that will closely align it" with the GT-R LM Nismo.
The point could be further driven home by the fact that the GT-R LM Nismo will begin its FIA endurance racing campaign next year, and the next GT-R is due to debut next year as a 2016 model. The expectation is that it will use a hybrid system possibly dubbed R-Hybrid and perhaps developed by Williams. Just like performance car makers Ferrari and Audi, Nissan wants its racing efforts to pay off with road car technology, company vice president Andy Palmer saying they "want to link technological linkages between future evolutions of the GT-R and evolutions of what we do in LMP1, and the two do go in both directions."
The bigger question is, with the GT-R getting hybrid assistance, will it also get the weight gain that usually comes with it? Enthusiasts would love to see the trend reversed, especially on a car that's already no lightweight.