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GM patent reveals new two-stage turbocharger

Modern turbochargers may be some of the best ever made, but performance is something that engineers are always trying to improve. According to GM Inside News, General Motors (GM) is hoping to alleviate some of the negative aspects of a two-stage turbocharger setup with a newly-patented design. The patent, that was filed on May 19, 2016, reveals a clever bypass system that allows the engine, a four-cylinder unit, to optimize both the low-pressure and high-pressure inlets for its respective functions. According to the filing, a conventional two-stage turbocharger setup is engineered to allow both turbines to operate simultaneously at low and mid engine speeds. At high engine speeds, only the low-pressure turbine works. The setup can't isolate either the low or high pressure side, which can impair low-end performance. GM's new two-stage turbocharger setup looks to eliminate this by linking the high-pressure turbo to the exhaust manifold through the high-pressure inlet duct. The low-pressure turbo is attached to the high-pressure turbo by a low-pressure inlet duct, which is linked to a connecting channel. A single actuator that is housed in the exhaust manifold creates a bypass that can opens the high-pressure inlet or close the connecting channel. Depending on what the engine load and speed is, the ECU guides the actuator—a single rotating spindle with discs corresponding to flanges on the high and low pressure sides—to isolate one of the two turbos. Isolating the turbos allow the respective inlets to be engineered for the best possible fluid dynamic performance. The setup should increase performance and decrease lag. There's no word on what car this setup will make an appearance on, but it will most likely be used in premium vehicles before trickling down to the rest of GM's vehicles. Related Video: News Source: GM Inside News, AutoGuide via GM Authority Cadillac Chevrolet GM Technology Sedan turbo patent engine turbocharging

Weekly Recap: Chevy and Alfa plot comeback strategies

Chevrolet and Alfa Romeo were two of the 20th Century's most iconic automotive brands. Chevy embodied America's post-war power and confidence. Alfa was the definition of the stylish Italian sports car. They reached halcyon heights in the 1950s and '60s, before declining precipitously amid new competition, changing consumer tastes, and uneven corporate management. Both say 2015 is the start of something better, and this week Chevy and Alfa laid out ambitious plans and showcased new cars that they hope will make them more relevant this year, and in the coming years. Each brand sits at its own crossroads, and their paths forward are as different as the Chevy Cruze and the Alfa Romeo Giulia. Chevy is still a sales beast, as evidenced by its volume of 4.8 million vehicles sold around the world last year. Chevy executives are fond of saying one of their cars is sold every seven seconds, which illustrates the strength and reach of a car brand that is the fourth largest in the world. "Make no mistake about it, we are a brand for the people," said General Motors North America president Alan Batey. But he wants consumers to want to buy a Chevy for its design and technology, not simply because it's affordable. That starts with all Chevys now featuring a distinctive a family look, with sporty cues from the Corvette or strong lines that riff on the Silverado pickup. "We want people to fall in lust with our cars," said Mike Pevovar, executive design director for Chevy passenger cars. "That initial emotional attraction has to be right on the exterior, and that's where form comes into play." Chevy is also loading up its cars, like the freshly unveiled 2016 Chevy Cruze, with technology to appeal to a younger crowd that prizes connectivity. The Cruze will offer Apple CarPlay and Android Auto with its MyLink infotainment system, and OnStar with 4G LTE and wifi. Seeking out younger buyers is also sound business practice: Millennials now outnumber Baby Boomers as the largest single age group in the United States. Younger buyers also can improve a brand's image, which is another area where Chevy would like to improve. Chevy ranks 82nd on Interbrand's Best Global Brand's list, behind 11 other automakers. Apple is No. 1. "We need our own variation of the Genius Bar," Batey said. 2016 Alfa Romeo Giulia View 3 Photos Meanwhile, Alfa is in different shape.

Some 2012-13 Chevy Volts may not have enough battery coolant

The 2012 and 2013 model year Chevrolet Volt extended-range plug-in vehicle may have a battery glitch caused by low coolant levels. No recall has been issued and General Motors is taking care of the issue at no cost to drivers. Some of the affected Volts may have lower-than-advisable coolant levels because of some pesky air pockets in the car's cooling circuit. When the coolant levels get too low, the charging system for the battery powering the car's onboard generator (i.e. the Rechargeable Energy Storage System, or the RESS) may be shut down, turning one's Volt into a run-of-the-mill gas-powered car, and a pricey one at that. The Car Connection says GM is advising owners of the '12 and '13 Volts to contact their local Chevy dealer for a free fix. GM representatives didn't immediately respond to a request for comment from AutoblogGreen for more details. We believe this is a separate issue than the one that brought 8,000 Volts back to the dealers for a battery coolant fix, what GM called a "voluntary customer satisfaction effort," a few years ago. General Motors sold 23,094 Chevy Volts last year after selling 23,461 Volts in 2012, so that fix-it list may get fairly lengthy. Check out a GM-Volt.com user thread related to this issue here. *UPDATE: Chevrolet spokesman Randy Fox confirmed in an e-mail to AutoblogGreen that the company issued a service bulletin to dealers that they may need to top off coolant levels on certain Volts because of the issue, and that the vehicle will "return to normal charging operation" once that's done.