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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

2019 GMC Sierra revealed with CarbonPro bed and new diesel engine

It's only March, and it's already been one hell of a year for trucks. January's Detroit Auto Show saw the reveals of the 2019 Ram 1500, 2019 Ford Ranger and the 2019 Chevy Silverado. The Chicago Auto Show brought new versions of the Toyota Tacoma and Toyota Tundra TRD Pro. Today, we finally got our first look at the Silverado's twin, the 2019 GMC Sierra. The truck features new styling, a new diesel engine and — on the Sierra Denali — a carbon fiber bed. As with every new full-size truck, the Sierra is larger than the outgoing model in almost every dimension, though exact dimensions haven't been revealed. For reference, though, the Chevy Silverado's bed is 7-inches wider than before. The new Sierra grille is more upright than before and features new C-shaped lighting. The Denali gets LED headlights, tail lights and fog lights. Both SLT and Denali trims get unique 22-inch wheels. As we saw in spy photos, the Sierra's interior is mostly just a copy of the Silverado's with some chrome accents sprinkled throughout. If you like the current truck interiors, you'll be pleased with the new model. Those hoping for a wholesale change will be left wanting. The big improvements inside include a full-color heads-up display, trailer hitch assist apps and cameras, and the rear-camera mirror found in models like the Chevy Traverse and Cadillac CT6. Safety and convenience features include a surround-view camera, blind-spot monitoring, pedestrian detection and low-speed automatic braking. Like the Silverado, there's been a significant effort to cut weight in the new Sierra. The 2019 model loses as much as 360 pounds compared to the current truck. It uses aluminum for the doors, hood and tailgate. Steel is still used for the fenders, roof and standard cargo box. The Denali, however, gets the real surprise here. Available only on the top-tier trim, the bed box will be constructed of carbon fiber rather than steel, saving 62 pounds. Carbon fiber only replaces the steel inner panels and floor. GMC says the carbon fiber will also help scratch and corrosion resistance. SLT and Denali models also get a new MultiPro tailgate. This is unique to the Sierra and separate from the Silverado's power assist unit. A new feature that helps one get into and out of the bed using an assist handle. The tailgate step has a maximum weight capacity of 375 pounds. There multiple positions that allow customers to extend the bed, or drop the center vertically to gain easier access to the back.

Autoblog's guilty pleasure cars

Guilty pleasures are part of life – don't even try to pretend like you don't have one (or two, or six). In the non-automotive space, this could come down to that secret playlist in your iPhone of songs you'll only listen to when you're alone; or think of that one TV show you really do love, but won't admit to your friends. I've got plenty, and so do you. Going back to cars, here's a particularly juicy one for me: several years ago, I had a mad crush on the very last iteration of the Cadillac DTS. Oh yes, the front-wheel-drive, Northstar V8-powered sofa-on-wheels that was the last remaining shred of the elderly-swooning days of Cadillac's past. Every time I had the chance to drive one, I was secretly giddy. Don't hate me, okay? These days, the DTS is gone, but I've still got a mess of other cars that hold a special place in my heart. And in the spirit of camaraderie, I've asked my other Autoblog editors to tell me some of their guilty pleasure cars, as well – Seyth Miersma, as you can see above, has a few choice emotions to share about the Mitsubishi Lancer Evolution. Read on to find out what cars make us secretly happy. Mercedes-Benz SL65 AMG This decadent convertible is the epitome of the guilty pleasure. It's big, powerful, fairly heavy and it's richly appointed inside and out. It's a chocolate eclair with the three-pointed star on the hood. Given my druthers, I'd take the SL65 AMG, which delivers 621 horsepower and 738 pound-feet of torque. That output is borderline absurd for this laid-back convertible. I don't care. You don't need dessert. Sometimes you just crave it. The SL line is about the feel you get on the road. The roof is open. The air, sun and engine sounds all embrace you. It's the same dynamic you could have experienced in a Mercedes a century ago, yet the SL gives you the most modern of luxuries. An Airscarf feature that warms my neck and shoulders through a vent embedded in the seat? Yes, please. Sure, it's an old-guy car. Mr. Burns and Lord Grantham are probably too young and hip for an SL65. I don't care. This is my guilty pleasure. Release the hounds. – Greg Migliore Senior Editor Ford Flex I drove my first Flex in 2009 when my mother let me borrow hers for the summer while I was away at college. The incredibly spacious interior made moving twice that summer a breeze, and the 200-mile trips up north were quite comfortable.