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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

Mark Reuss: GM can't afford product 'misses,' has 'thought about' CT6 V-Series

Mark Reuss is a busy man. He oversees General Motors' global product portfolio, an all-encompassing task for a company that sold more than 9.9 million cars and trucks last year. When GM launches a well-received product, like the road-going rocket ship that is the Chevrolet Corvette Z06 – he gets credit. When the company stumbles with the slow-selling Chevy Malibu or grapples with fallout from the decade-old Saturn Ion and its flawed ignition switch, he gets blamed. GM owners, the press and sometimes the federal government, demand answers. Bob Lutz famously held the job before Reuss. So did Mary Barra, who's now GM's chief executive. There's a New GM, but the lineage is connected to a long history. When he's not thinking product, Reuss, an executive vice president, also runs the purchasing and supply chain for the company, which is still one of the largest industrial empires in the world. We caught up with Reuss on the floor of the New York Auto Show, where GM had just rolled out two crucial new products: the 2016 Cadillac CT6 and the 2016 Chevrolet Malibu. Speaking with a small group of reporters, Reuss delved into a variety of subjects, including the new Malibu, Cadillac's future (he thinks the ATS-V is going to "flame the M3 and M4"), and other topics. On fixing the Malibu: "We can't miss. We can't have those kinds of misses [like the previous generation] on our cars and crossovers and trucks. We can't do that. If we do that, we give a reason for someone to go buy something else. It's that simple. "On a car like the Malibu we have a chance to really fix all of that, which we have, and then lead. Then you've got a real opportunity there. So that's what we've really been focused on here – to fix those things." He later added: "We need that car here to transform Chevrolet desperately because it's the heart of the market. And when you think of Chevrolet, people will come back and think about what we did with the [new] Malibu and the Cruze... It's hugely important to us." On Cadillac: "If we go out and try and out-German the Germans, it's probably not going to work. We've got an opportunity here generationally where there's a lot of people younger than me that have parents that drove BMWs and Mercedes, and I think there's an opportunity there for those people to drive something different than what their parents did, and I think that's always been an opportunity in the auto industry if you look at the history of it.

Chevy Spark EV could be coming to Midwest later this year

Ohio is not known as a hotbed of EV sales – if anything, the state is a bit anti-EV, thanks to a legislative fight against Tesla's direct sales model – but it might be on Chevrolet's short list to expand the market for the Spark EV in the near future. The latest official GM press release on the battery-powered Spark still says the car is "available exclusively in California and Oregon," but Hybrid Cars found four Ohio dealerships that list a Spark EV on their websites, with hints the the car will be coming to the Midwest state by the end of the summer. See, for example, here, here, here and here. But that's probably not going to happen, according to Randy Fox, GM communication's manager for passenger cars. Fox told AutoblogGreen that, "At this point in time, we don't have any official plans to expand the Spark EV beyond California and Oregon." The reason is that California and Oregon have the infrastructure to support EVs, Fox said, and GM wants to be able to support its EV customers. "We are continuing to look at other options," he said. "The selling point for electric cars today is not advertising, it's eyeballs, it's peer exposure" – John O'Dell John O'Dell, a senior editor at Edmunds.com, told AutoblogGreen that, "It makes sense for [GM] to expand sales and it makes sense to do it in a quiet manner, to get these vehicles on the road. The selling point for electric cars today is not advertising, it's eyeballs, it's peer exposure. If someone in my neighborhood has one and he likes it, then maybe I can trust him. So it's important to get these vehicles on the road." Chevy sold 182 Spark EVs last month, a significant increase over the 98 sold in April. That's still small potatoes compared to the 3,000+ Nissan Leaf EVs sold last month, but making the electric Spark available in Ohio, say, or GM's home state of Michigan could boost those numbers. AutoblogGreen called a few dealerships in Michigan to see what they had heard. One salesman said he didn't think GM had started production yet but the inventory manager for another dealership said the Spark EV is scheduled to arrive in the Midwest in "roughly the fourth quarter." What would GM's incentive be to offer the car in markets outside of California where it can gain ZEV credits with each sale?