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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

Sabine Schmitz to compete in WTCC race at Nurburgring, hopes for rain

The World Touring Car Championship is set to return to the Nurburgring this year after a 30-year absence. Who better, then, to lead the pack than Sabine Schmitz? One of the most skilled drivers around the Norschleife, 45-year-old Schmitz has been known to compete in the VLN series and in the 24-hour race at the Nurburgring (which she's won twice), and regularly drives tourists on hot laps around the Green Hell. Nobody can drive the circuit better than Schmitz when the rain starts to fall, and fall it often does in the German spring, but she'll have a new challenge on her hands when she makes her WTCC debut in a Chevy Cruze for the Munnich Motorsport team for the German round next month. It'll be interesting to see how Sabine does in the race, given that she has no experience with the vehicle she'll be driving, but has immense knowledge of the notoriously difficult track. She'll have the chance to acclimate a little during the WTCC test session at the 'Ring later this month, and hopes to compete in one of the two races – in Morocco or Hungary – before tackling her home track in unfamiliar machinery. News Source: WTCC via YouTube, BridgeToGantry.comImage Credit: Newspress Celebrities Hirings/Firings/Layoffs Motorsports Chevrolet wtcc

2020 Chevy Silverado HD vs. 2019 Ram, Ford heavy duty trucks: How they compare on paper

Last year was all about the latest in light-duty full-size pickup trucks, so this year, Ram, Ford and Chevy are launching the heavy-duty variants. The first out of the gate is the redesigned 2019 Ram 2500 and 3500 HD, and Ram dropped all the pertinent specs with the reveal. Chevy followed with the new Silverado HD in Chicago, and Ford revealed updates to the Super Duty at the same show. Ford hasn't released details on output, payload capacity, towing capacity or pricing for the updated Super Duty. As such, we'll be comparing the current Super Duty with the all-new Silverado HD and Ram HD. Both Chevy and Ram have revealed full specs for each of their respective trucks, leaving out only pricing, which we've estimated based on the outgoing models. You can see the raw details in the chart below, followed by extra information and analysis. Some things to keep in mind: These specifications cover all versions of the Ram HD, Silverado HD and Super Duty, such as 2500 and 3500 models, and all the way up to F-450. Specifications can vary widely based on engine, drivetrain, cab and bed configurations, so be sure to take a close look at the specific model you're interested in when you get particularly serious about buying. And of course, be sure to check out our car comparison tool if you'd like to look at other trucks on the market. Engines and drivetrains All three of these trucks offer gasoline and diesel engines, but only the Ram has two versions of the diesel. Starting with gas engines, Ram's 6.4-liter V8 has the power advantage with 25 more horsepower than the next-most-potent Super Duty, but the new Silverado HD's 6.6-liter V8 takes the torque crown at 464 pound-feet, nearly 35 more than the other two gas engines. The Ram is also the only one to pair an eight-speed automatic with the gas engine, whereas the Ford and Chevy make do with a six-speed. With diesel engines, horsepower is a weak point for the Ram. The Ram's entry-level turbo 6.7-liter inline-six is the weakest, as the only one with under 900 pound-feet of torque and under 400 horsepower. Even the high-output version only makes 400 horsepower, while the Chevy makes 445 and the Ford 450. But the tables turn with torque, as the Ram makes a best-in-class 1,000 pound-feet followed by the Ford's 935 and the Chevy's 910. Both the Ram and the current Super Duty diesels each get a six-speed automatic, but the new Silverado HD's diesel gets a 10-speed unit.