2.5 Sedan Bargain Corner Low Miles 4 Dr Cvt Gasoline 2.5l 4 Cyl Dark Slate 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 Leaf EVs slip through French village to make a quiet point

Bjork's 1995 freak-out hit It's Oh So Quiet may have reflected the singer's oddball Icelandic sensibilities, but Nissan is making the concept of relative silence a French thing. The Japanese automaker recently promoted its all-electric Leaf by staging a mini-rally through what it called "one of the quietest villages in Europe." And with the exception of a couple damaged trash bins and a destroyed rear-view mirror from an old-school archway, the race kept the drivers wide awake but everyone in the Southern French village in Provence Alpes Cote d'Azur sleeping. Nissan sent four vehicles on a five-kilometer jaunt through the village in the wee morning hours. Screeching tires and a couple booms notwithstanding, the company said everyone in town stayed snoozing. There was a broader purpose to this exercise, of course, which Nissan blatantly admits was a stunt. Nissan was helping celebrate 19th Annual International Noise Awareness Day (INAD), which took place on Wednesday and highlighted the emotional and health issues as well as high blood pressure and insomnia caused by excessive exposure to noise. Check out Nissan's press release below, where you'll also find the video. This content is hosted by a third party. To view it, please update your privacy preferences. Manage Settings. NISSAN LEAF CELEBRATES INTERNATIONAL NOISE AWARENESS DAY WITH A NIGHTTIME "SILENT RIDE" ROLLE, Switzerland – To mark the 19th annual International Noise Awareness Day (INAD), Nissan has taken to the streets of one of Europe's quietest villages during the middle of the night with a silent "ride" of its 100 percent electric Nissan LEAF. The activity, complete with a start and finish line in Provence Alpes Cote d'Azur, was designed to demonstrate the noise reduction levels of the Zero Emissions car compared to traditional combustion engines. The World Health Organization (WHO) states at least 13.5 percent of Europeans are exposed to road traffic noise at levels exceeding 55 dB, which is considered detrimental to human health*. The medical effects of noise levels include insomnia (50dB), obesity (50dB), psychic disorders (60dB) and reduction in life expectancy (50dB)*. As a result, Nissan has filmed a 'silent ride' to help support INAD in raising awareness about noise pollution levels across Europe.

Autoblog Podcast #380

Episode #380 of the Autoblog podcast is here, and this week, Dan Roth, Chris Paukert and Seyth Miersma talk about the Fiat-Chrysler five-year plan, the seeming demise of the Nissan Cube, and proposed legislation to require speed limiters with a 68-mph maximum on America's tractor trailers. We start with what's in the garage and finish up with some of your questions, and for those of you who hung with us live on our UStream channel, thanks for taking the time. Check out the new rundown below with times for topics, and you can follow along down below with our Q&A. Thanks for listening! Autoblog Podcast #380: Topics: Fiat-Chrysler five-year plan Nissan Cube on the way out? Big rig speed limiters coming? In the Autoblog Garage: 2015 Mercedes-Benz S63 AMG 2014 Chevrolet Sonic RS Sedan 2014 Honda Odyssey Touring Elite Hosts: Dan Roth, Chris Paukert, Seyth Miersma Runtime: 01:44:17 Rundown: Intro and Garage - 00:00 Fiat Chrysler Plan - 29:40 Nissan Cube - 01:07:33 Semi Speed Limiters - 01:17:33 Q&A - 01:27:35 Get the podcast: [UStream] Listen live on Mondays at 10 PM Eastern at UStream [iTunes] Subscribe to the Autoblog Podcast in iTunes [RSS] Add the Autoblog Podcast feed to your RSS aggregator [MP3] Download the MP3 directly Feedback: Email: Podcast at Autoblog dot com Review the show in iTunes Auto News Earnings/Financials Plants/Manufacturing Podcasts Rumormill Chevrolet Chrysler Dodge Fiat Jeep Nissan nissan cube speed limiters