Chevrolet : 350 5.7 Silverado 1500 Swb on 2040-cars

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GM is the latest automaker accused of diesel emissions cheating

Volkswagen and Ram need to make room on the diesel-emissions bench for General Motors. America's largest automaker was accused in a lawsuit on Thursday of rigging hundreds of thousands of diesel trucks with at least three so-called defeat devices to ensure that the trucks would meet federal and state emission standards, even if they generated more pollution in real-world driving. According to the complaint, on-road emissions testing conducted for the plaintiffs found that Duramax-equipped trucks produced NOx pollutants, comprised of nitrogen and oxygen atoms, two to five times higher than legally permitted, and "many times" higher than their gasoline counterparts. The proposed class-action lawsuit was filed in federal court in Detroit on behalf of people who own or lease more than 705,000 Chevrolet Silverado and GMC Sierra pickup trucks fitted with "Duramax" engines from 2011 to 2016 model years. The lawsuit seeks remedies including possible refunds or restitution for lost vehicle value, plus punitive damages. It adds to legal problems for Detroit-based GM, which has already paid about $2.5 billion in penalties and settlements over faulty ignition switches linked to 124 deaths. GM joins at least five automakers whose diesel emissions have been scrutinized by regulators or consumers. They include VW, which has admitted to cheating; Mercedes-Benz parent Daimler; Fiat Chrysler Automobiles, Peugeot and Renault. GM spokesman Dan Flores called the claims "baseless," and said the trucks comply with US Environmental Protection Agency emissions standards and California's own tough standards. Shares of GM were down 69 cents, or 2.1 percent, at $32.50 in afternoon trading, after earlier falling to $31.93. The GM lawsuit was filed by several law firms, including Hagens Berman Sobol Shapiro, which helped reach multibillion-dollar settlements with VW on behalf of drivers and dealers. The case is Fenner et al v General Motors LLC et al, US District Court, Eastern District of Michigan, No. 17-11661. The named plaintiffs are Andrei Fenner of Mountain View, California and Joshua Herman of Sulphur, Louisiana. They said they would not have bought their respective 2011 Sierra and 2016 Silverado trucks, or would have paid less for them, had they known about the alleged rigging. Joseph Spak, an RBC Capital Markets analyst, in a research report said "negative publicity" from the lawsuit could drive buyers to trucks from Ford or even Fiat Chrysler's Ram.

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 applies for LT5, LTX trademarks... are new small block variants coming?

Recently discovered General Motors trademark applications for LT4, LT5, LT88 and LTX have observers wondering what kind of high-performance offerings could be on their way. A new LT4 would mark a return of the engine designation first used on the Corvette Grand Sport, SLP Pontiac Firehawk and SLP Chevrolet Camaro SS from 1996 and 1997. Supposition at Corvette Forum - which provided advance intel on the C7 like these leaked images - believes a new LT4 could go into the high-performance trim of the next-gen, 2015 Camaro that would be more powerful than the 580-horsepower Camaro ZL1.
Seeing an LT5 again would also be déjà vu - in its former life it was a 5.7-liter V8 for the C4 Corvette ZR-1 from 1990-1994 designed by Lotus, producing from 370 hp to 405 hp. A mix of rumor and hope is that the new LT5 will be a supercharged evolution of the 6.2-liter LT1 (pictured) placed in the new C7 Corvette, and that it will go into the C7 version of the ZR1 pumping out something like 700 hp.
The LTX trademark is, as with that last letter, a complete mystery. If the "X" isn't a generic way to denote the whole LT family, it's wondered if it LTX could refer to a crate motor offering like the LSX.