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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

Ram 1500 bests new F-150 in MT pickup shootout

Ford's 2015 Ford F-150 is a technological tour-de-force, what with its aluminum-intensive construction and its powerful and efficient new 2.7-liter EcoBoost engine option. But now that it's hit the market, it's time to get down to brass tacks and find out how just the latest F-150 actually stands up to its rivals in the hyper-competitive fullsize segment. Motor Trend is among the first to round up the Ford (in Lariat 2.7-liter 4X4 guise here) and put it up against the Ram 1500 Outdoorsman EcoDiesel 4x4 and 5.3-liter-equipped Silverado 1500 LTZ Z71 to find out how Dearborn's new-think truck measures up. The test put the trio through over 1,000 miles of tough driving in California and Arizona in a variety of conditions from just cruising around unladen to hauling a trailer. MT found all three trucks to be competent, but the most praise got heaped on the Ram and the Ford, with the Chevrolet falling a step behind its competitors in many tests. Among the Ford's most-liked features was its 2.7-liter, twin-turbo V6 that helped make the F-150 easily the quickest of the group, with some editors saying the engine felt about the same whether driving around with cargo in the bed or not. There was some minor turbo lag during acceleration while trailering, but that issue affected the Ram, too. The Ram's powertrain was lauded, as well. The EcoDiesel was torquey around town, and the 1500's combination of an eight-speed automatic and air suspension was judged to be the best of the lot. It was the most difficult to get into the bed, though. The Ram also won the fuel economy award by netting 20-miles-per-gallon city and 28-mpg highway in the test to beat its Environmental Protection Agency ratings of 19/27. The Ford's EcoBoost managed 17/22, one mpg off each from the EPA numbers, and using a lot of throttle really depleted its efficiency. As MT notes, however, it would take time for the diesel's mileage savings to pay off at the pump for these two trucks. In the end, the Ram just barely eked out the win, with the title partially earned because of "the Ford's unknown maintenance and aluminum repair costs," according to MT. Go check out the full comparison to read all of the details, then let us know what you think in Comments.

IIHS Crash-tests Expose American Muscle Cars' Weaknesses | Autoblog Minute

Turns out American muscle cars aren?t that strong according to IIHS crash tests. The Insurance Institute for Highway Safety put three iconic American sports cars through a range of performance crash tests. Chevrolet Dodge Ford Autoblog Minute Videos Original Video crash test camaro challenger