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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

GM executive chief EV engineer says reducing cost of plug-in vehicles is 'huge priority'

As we know, another major automaker investing heavily in electrified vehicles is General Motors, and it's doing things much differently than rivals BMW, Ford or Nissan. The Chevrolet Volt extended-range EV is a modest seller at its $35,000 sticker price but a huge hit with owners. The Chevy Spark BEV, still in limited availability, puts smiley faces on its owners and drivers. The just-introduced Cadillac ELR, a sharp-looking, fun-driving $76,000 luxocoupe take on the Volt's EREV mechanicals, has admittedly low sales expectations. With this interesting trio in showrooms and much more in the works, the third vehicle electrification leader I collared for an interview at Detroit's North American International Auto Show (see #1 and #2) was Pam Fletcher, GM's executive chief engineer, Electrified Vehicles. ABG: Why do your EREVs need four-cylinder power to extend their range when BMW's i3 makes do with an optional 650 cc two-banger? "We designed [the Volt and the ELR] to go anywhere, any time" - Pam Fletcher PF: I get that question all the time: why not something smaller? You don't really need that much. You use the electric to its ability, then you just need to limp. But we designed those cars to go anywhere, any time, and we don't want their performance to be compromised. If you're driving through the mountains, we don't want you to be crawling up grades, or to be limited on any terrain. So it's optimized to be able to travel literally the biggest grades and mountain roads around the globe at posted speeds. Because what if you can't? Another good reason: when the engine is on, you have to run it wide open throttle, max speed, most of the time. And while we can do a lot with acoustics, and the ELR has active noise cancelation, a small-displacement, low cylinder-count engine at high speed, high load all the time isn't something you want to live with. That's how we came up with the balance we did among the key factors of performance, NVH [noise, vibration and harshness] and range. ABG: Where you go from here? Is the range-extender engine due for an update? PF: We know and love the current Volt, and there is still a lot of acclaim about it, so we think it's a good recipe. But we are heavily in the midst of engineering the next-generation car, which I think everyone will love and be excited about.

These are the five most ridiculous attacks on the Chevy Volt [w/videos]

It's been a long, strange trip for the Chevy Volt from the time when the now-odd-looking concept version (above) was introduced at the 2007 Detroit Auto Show to today. And now, General Motors announced that the second-generation Chevy Volt will make an appearance at the 2015 Detroit show in January. This debut represents a victory for GM with what has easily become the most politicized car of the 21st Century. There are plenty of reasons for someone to criticize the Volt, but what's amazing is just how much anti-Volt energy has been spent not on things like the styling or how the EREV setup is not as efficient as a pure-EV powertrain. As we wait for more official information on the new Volt, we thought it would be fun to go back and look at some of the most wildly incorrect reporting and strangest attacks on the Volt from the archives. There is so much good stuff out there, it was hard to pare the list down, but these are our five favorites. Amazingly, they're not all clips from Fox News. Check 'em out below. 5. GM Is Going To Stop Making The Chevy Volt In The US Do you remember when GM was about to move Volt production to China? Well, yeah, this was reported back in early 2012 when a GM executive mentioned that the automaker would get benefits of building the Volt in the places where it sells them. This was spun into a story of GM taking Obama bailout money and then running to China. The Blaze was not happy: "Given the fact that Federal government helped itself to millions and millions of taxpayer dollars under the pretense that it was going to combat high unemployment by creating 'green jobs,' it would seem that moving research and development (and possibly manufacturing) overseas is slightly, well, counterproductive." Well, of course, that never happened. There's no way to say that GM will never build a version of the Volt in China, but the news we hear rumors of these days is that GM is going to move production of more Volt parts (specifically, the motors) to Michigan from overseas. 4. The Chevy Volt Is A Fire Trap There has never been a Volt that just spontaneously lit up while driving down the road. Yes, there were Volts that caught on fire. Yes, that's a scary thing. But there has never been a Volt that just spontaneously lit up while driving down the road. These were crashed test vehicles with destroyed batteries and plugged-in vehicles that were not the cause.