2024 Sentra S 4 Doors Only 71 Miles Brand New 1 Owner 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.

Even Ferrari swept up in latest Takata recall expansion

The scope of Takata's deadly airbag problems continues to widen. Eight manufacturers announced recalls Friday that affect more than 12 million vehicles, according to documents filed with federal regulators. The automakers include Honda, which is recalling 4.5 million units, Fiat Chrysler with 4.3 million, Toyota with 1.65 million, and Subaru, which is recalling almost 400,000. Some of these cars include the Saab 9-2x and Pontiac Vibe that Toyota and Subaru made for General Motors. Mazda will recall 730,000 vehicles and Nissan has 400,000 affected units. The smallest numbers were posted by Mitsubishi, with 38,000 Lancers manufactured from 2006 to 2007, and as a noteworthy high-end manufacturer, Ferrari is calling back 2,800 vehicles. These are all US-market cars. Beyond America, the Japanese Transport Ministry has announced seven million additional vehicles will be recalled, which means 19.6 million vehicles across the globe are affected by recalls announced. The defects have been traced to an insufficiently manufactured airbag inflator, which lacks a drying agent that would prevent the inflators from deteriorating over time. Thirteen deaths have been linked to the faulty airbags, which have become unstable and are prone to exploding and showering vehicle occupants with lethal amounts of metal shrapnel. A private equity firm, KKR & Co., has been named in a possible buyout of the struggling Takata. Related Video: News Source: ReutersImage Credit: Shutterstock Government/Legal Recalls Ferrari Honda Mazda Automakers Mitsubishi Nissan Pontiac Subaru Toyota Saab Safety

Nissan GT-R drag races Swiss fighter jet

Proving that speed is fun in any language, Nissan's German arm recently pitted a GT-R up against an ex-Swiss Air Force fighter jet, called the Hawker Hunter. Now the idea of a car-versus-plane drag race is nothing new, but this is the first time we can recall a GT-R being involved.
While this Nissan video is almost a month old, we're pretty sure you won't be disappointed by the action, which shows the two high-speed machines racing along the two-kilometer runway. We don't want to ruin the suspense, so scroll down for the latest matchup of sports car versus fighter jet.