1972 Chevrolet Malibu Sport Coupe on 2040-cars

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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

This map reveals the cleanest vehicles based on location

Naysayers love to point out how dirty the electricity grid mix is when it comes to charging electric vehicles. Curmudgeons are eager to jump into any conversation about EVs to enlighten the lucky listeners about how plug-in cars contribute to pollution, sometimes even throwing in a dash of climate-change denial for good measure. (Thanks, buddy. Pray, tell me more about the plight of oppressed SUV owners.) Unless someone buys an EV just because they think they're cool (which, yeah, they often are), they probably have at least a passable understanding of their environmental pros and cons. As many EV owners are already aware, location has a lot to do with any particular plug-in car's carbon footprint. Still, there's always more to know, and knowledge is not a bad thing, especially if one uses it to do the right thing. That's why this handy-dandy map from Carnegie Mellon University is so interesting. CMU researchers have compiled information about the lifecycle greenhouse gas emissions of various EVs based on where they're charged, as compared to gasoline-powered vehicles. The researchers looked at the Nissan Leaf, Chevrolet Volt, and Prius Plug-In Hybrid versus the gasoline-dependent Toyota Prius hybrid and the stop-start-equipped Mazda3 with i-ELOOP and compared grams of CO2 emitted per mile. CMU takes into account the grid mix, ambient temperature, and driving patterns. CMU takes into account the grid mix based on county, as well as ambient temperature and driving patterns in terms of miles traveled on the highway or in the city. For instance, if you drive a Nissan Leaf in urban areas of California, Texas, or Florida, your carbon footprint is lower than it would be if you were driving a standard Toyota Prius. However, if you charge your Leaf in the Midwest or the South, for the most part, you've got a larger carbon footprint than the Prius. If you live in the rural Midwest, you'd probably even be better off driving a Mazda3. Throughout the country, the Chevrolet Volt has a larger carbon footprint than the Toyota Prius, but a smaller one than the Mazda3 in a lot of urban counties in the US. The Prius and Prius Plug-In are relatively equal across the US. Having trouble keeping it straight? That's not surprising. The comparisons between plug-in and gasoline vehicles are much more nuanced than the loudest voices usually let on.

Cadillac CT6 production ceases January 2020 as part of D-Ham layoffs

General Motors filed paperwork under the Worker Adjustment and Retraining Notification Act with Michigan's Department of Labor and Economic Opportunity this week, detailing events to come at the automaker's Detroit-Hamtramck Assembly Plant. Starting February 28, 814 salaried and hourly workers at D-Ham, as its called, will be laid off. The 753 workers represented by the UAW will begin receiving offers in January to relocate to facilities in Michigan and Ohio, or buyout offers. As the 4-million-square-foot plant winds down through April 3 to a skeleton crew, the Cadillac CT6 ceases production in January 2020, and the last Chevrolet Impala comes off the line on February 28. The loss of the CT6 represents the end of Cadillac's latest brief, and highly regarded, adventure into flagship sedans. It might also mean the end of the 4.2-liter Blackwing twin-turbo V8 engine, at least for the moment. Both casualties are calamities. The death of the Impala closes the door on a nameplate in production for 52 years since 1957, having started off as a top-tier trim for the 1958 Bel Air known as the Bel Air Impala, once advertised with the line, "Lets you know you're the boss." As part of the new four-year labor agreement with the UAW, GM is keeping D-Ham open to build a new line of battery-electric vehicles, ultimately investing $3 billion and tripling employment to 2,225 workers when fully operational. The agreement described the coming EV as a "van" that would commence production in late 2021, but various reports say what's actually coming is a range of premium EVs in pickup and SUV bodystyles under the program codename BT1. The easy predictions put an electric GMC Sierra and Cadillac Escalade among the EV fold, but not until 2023, according to auto industry forecaster LMC Automotive. Before that, LMC claims an electric van will debut in late 2021, along with a battery-powered rebirth of the Hummer brand in pickup and SUV forms, also in late 2021.