2006 Chevy Silverado Crew Cab 4x4 4.8l V8 Auto 4wd Low Mileage on 2040-cars

Auto blog

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 admits goal of 500,000 EVs by 2017 won't be met

After a little over four years of Chevy Volt sales, General Motors has a better handle on how many people it expects will buy cars with plugs. And it's less than the company thought back in 2012, when then-senior vice president of global product development, Mary Barra, said that GM expected to sell 500,000 "vehicles with electrification" by 2017. In a sustainability report released this week, GM says that half-million vehicle target will not be met but that it still, "believes the future is electric." In the report, GM says that, "For our commitment to electrification, our forecasted outlook currently projects us, along with the broader automotive industry, falling short of expectations for 2017. ... We continue to aspire to our stated goal." GM's electric lineup includes the Volt, the recently popular Spark EV, the slow-selling Cadillac ELR and upcoming Malibu Hybrid, CT6 plug-in hybrid and eAssist technology in the Buick LaCrosse and Regal. GM says it has 180,834 electrified vehicles on the road in the US today. In 2013, it had 153,034; 95,578 in 2012, and 39,843 in 2011. The company's next big plug-in vehicle will be the second-gen Chevy Volt, which is coming to market later this year, followed by the 200-mile Bolt EV coming, we think, in 2017. GM Employees on Mission to Transform Transportation Sustainability report outlines vehicle and manufacturing progress; sets new targets 2015-05-07 DETROIT – General Motors' just-released sustainability report chronicles efforts by the company's 216,000 employees to live out GM's newly defined purpose and values by earning customer loyalty, applying meaningful technology advances and improving the communities where it does business. These actions – led by CEO Mary Barra – further drive sustainability into the company's culture through building safer and smarter vehicles with less environmental impact. "GM will take a leading role in the auto industry's transformation as it undergoes an unprecedented period of change," said Bob Ferguson, senior vice president, GM Global Public Policy. "From GM's labs to its assembly lines, our people are driving the world to a better place through improved mobility." The company believes the future is electric, with billions of investment to support an all-in-house approach to the development and manufacturing of electrified vehicles. It now counts 180,834 on the road in the U.S – up from 153,034 in 2013.

Is the skill of rev matching being lost to computers?

If the ability to drive a vehicle equipped with a manual gearbox is becoming a lost art, then the skill of being able to match revs on downshifts is the stuff they would teach at the automotive equivalent of the Shaolin Temple. The usefulness of rev matching in street driving is limited most of the time – aside from sounding cool and impressing your friends. But out on a race track or the occasional fast, windy road, its benefits are abundantly clear. While in motion, the engine speed and wheel speed of a vehicle with a manual transmission are kept in sync when the clutch is engaged (i.e. when the clutch pedal is not being pressed down). However, when changing gear, that mechanical link is severed briefly, and the synchronization between the motor and wheels is broken. When upshifting during acceleration, this isn't much of an issue, as there's typically not a huge disparity between engine speed and wheel speed as a car accelerates. Rev-matching downshifts is the stuff they would teach at the automotive equivalent of the Shaolin Temple. But when slowing down and downshifting – as you might do when approaching a corner at a high rate of speed – that gap of time caused by the disengagement of the clutch from the engine causes the revs to drop. Without bringing up the revs somehow to help the engine speed match the wheel speed in the gear you're about to use, you'll typically get a sudden jolt when re-engaging the clutch as physics brings everything back into sync. That jolt can be a big problem when you're moving along swiftly, causing instability or even a loss of traction, particularly in rear-wheel-drive cars. So the point of rev matching is to blip the throttle simultaneously as you downshift gears in order to bring the engine speed to a closer match with the wheel speed before you re-engage the clutch in that lower gear, in turn providing a much smoother downshift. When braking is thrown in, you get heel-toe downshifting, which involves some dexterity to use all three pedals at the same time with just two feet – clutch in, slow the car while revving, clutch out. However, even if you're aware of heel-toe technique and the basic elements of how to perform a rev match, perfecting it to the point of making it useful can be difficult.