Nissan: 350z 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.

Do you guys like trucks?

Do you guys like trucks? If the answer is yes, boy do we have the show for you! The 2018 North American International Auto Show is lousy with 'em. Yeah, we saw the new Ram 1500, Chevy Silverado and Ford Ranger, but that's just scratching the surface. There are big trucks, little trucks, clean trucks, dirty trucks, old trucks, new trucks, red trucks, blue trucks. It's like a Dr. Seuss book. Anyway, we made a little video for you truck nuts (see what I did there?). Check it out above, and if you're looking for more serious coverage of the Detroit Auto Show, we've got it, along with a ton of images and other videos from the show floor. Enjoy! Related Video: Humor Detroit Auto Show Chevrolet Ford GMC Honda Lincoln Nissan RAM Toyota Truck Videos Original Video 2018 detroit auto show

2013 Nissan Pathfinder: July-September 2013

This Nissan is the most in-demand long-term vehicle we've ever had.
They may not readily fall into the sweet spot of driving enthusiasts, but our year-long test of this Nissan is proving to be an object lesson in why crossovers are so popular - especially large ones like our three-row Pathfinder. In fact, it's been so busy that it's hardly been at a standstill long enough to pen an update, which is why this one is late. Simply put, this Nissan is the most in-demand long-term vehicle we've ever had, racking up more miles and more long-distance trips than any LT vehicle in the Autoblog stable.