2007 Chevrolet Silverado 1500 4x4 Z71 Ltz on 2040-cars

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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 ending stop-sale order on heavy-duty trucks

General Motors responded to an inquiry from Autoblog regarding a stop-sale order on its full-size heavy-duty pickup trucks. Here's GM's official statement. GM is committed to building the highest quality products possible. We paused delivery on a small number of HD pickups with the 6.6 liter Duramax engine last week to finalize an investigation into a potential quality issue. The investigation has been completed and the stop sale will be lifted for the small number of vehicles at dealerships.Customers can be assured GM’s heavy duty pickups are covered by a 5 year/100,000 mile powertrain warranty. The original article continues below. General Motors has reportedly sent its Chevrolet and GMC dealers a stop-sale order that applies to some examples of the 2022 Silverado HD, the 2022 Silverado MD, and the 2022 Sierra HD. The units affected by the stop-sale order may develop an engine-related problem. Citing anonymous sources, website GM Authority wrote that the Duramax 6.6-liter turbodiesel V8 in the affected trucks can hydrolock, which means liquid could enter the cylinders and cause a substantial amount of damage. The report does not specify where the liquid would come from; hydrolocking can happen by driving through a deep puddle of water, for example, but a large amount of coolant can cause it as well. The publication adds that the stop-sale order was assigned internal reference number N222362910. It also notes that the trucks included in it can't be sold, delivered to buyers, traded with another dealer, sent to auction, or even used for demonstration purposes until further notice. Earlier in April 2022, GM Authority reported that General Motors planned to buy back an unspecified number of Silverado HD and Sierra HD trucks due to quality-related issues with the 6.6-liter V8. Details about the problems experienced by customers haven't been released; all we know is that each truck will be replaced, though the replacement may not have the same equipment due to the ongoing chip shortage. Related video:

2016 Camaro gets most revealing tease yet

Chevrolet started its long teaser campaign for the 2016 Camaro by just revealing the exhaust manifold and front frame, but as time has passed the company has slowly unveiled more. In the latest glimpse ahead of the pony car's May 16 debut, we're actually getting to see the model's profile completely undisguised. As suggested by the recent tease of the rear and hood, the 2016 Camaro wears a sharper, more angular design than the current model. This is especially the case when you look at the taut lines making up the rear. Chevy claims that the new shape underwent 350 hours of wind tunnel tests to be able to generate left lift, improve cooling and reduce wind noise in the cabin. A smooth underbody pan is among the aerodynamic tweaks, and it runs from underneath the front grille to the center of the Camaro. Chevy asserts that all of the changes at the front help reduce lift by 30 percent. Related VIdeo: 2016 Camaro is all about the Aero Total aerodynamic lift improved by 30 percent for improved stability 2015-05-11 DETROIT – After 350 hours of wind tunnel testing – often 24 hours a day – the new Camaro will slip more easily through the wind, and drivers of the Camaro SS will experience a marked improvement in reduced aerodynamic lift. These changes illustrate the lengths the aerodynamics team went to for improved performance, stability, cooling and lower wind noise intrusion "The importance of aerodynamics increases exponentially as we increase vehicle performance," said Kirk Bennion, Exterior Design manager. "As engine output increases, we need more engine cooling. As acceleration and top speeds climb, we need to reduce lift for better high-speed stability. However, we cannot make any changes at the expense of increasing drag, which can hurt fuel economy. "To balance these different aerodynamic targets, we tested literally hundreds of changes on the new Camaro, millimeters at a time." For example, the initial design called for the lower grille bars to be set at a 20-degree angle to the horizon. However, after meticulous testing, the team improved engine-cooling airflow by 1 percent by shifting the angle to 13 degrees – a change that achieved the airflow target while maintaining the original grille design. And rather than a traditional front air dam to reduce aerodynamic lift, the team developed a flush belly pan that stretches from the front grille to the center of the vehicle.