2008 Chevrolet Trailblazer on 2040-cars

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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.

Buick Velite is a not-so-Volt-like plug-in hybrid concept for China

Is the Buick Velite a Volt by any other name? That's a question worth asking after General Motors said that the Buick Velite concept vehicle will make its global debut at the Guangzhou Auto Show later this month. GM says the car "will provide a template for upcoming models being launched under the Buick Blue new energy vehicle strategy." Whether that means the Velite is a variant of the second-generation of the Chevrolet Volt extended-range plug-in is open to interpretation. Some automotive publications, including Autoweek, are saying that's the case, but GM China doesn't mention the Volt in its press release, only saying that the car is a "high-performance" plug-in hybrid vehicle. As we know, GM doesn't use the "PHEV" descriptor for the Volt, which makes us thing the Velite's powertrain is more like the Cadillac CT6 PHEV. Either way, the concept was developed by the Pan Asia Technical Automotive Center (PATAC), which is a joint venture between GM and Shanghai-based SAIC. As far as the name, GM has been shopping the Velite moniker around for a while now. The automaker first used Buick Velite for the convertible concept vehicle it showed off at the 2004 New York Auto Show. More recently, GM in 2014 filed to use the name for the US variant of its Opel Cascada four-seat convertible model, which debuted in 2013. As for the second-generation version of the Volt, that model appears to be gaining favor in the US. Domestic sales of the Volt through October have surged 64 percent from a year earlier to more than 18,500 units. The new version boosted its all-electric range by 40 percent to 53 miles while increasing its power output by 20 percent. Related Video: News Source: General Motors via Autoweek, Automotive News-sub.req. Green Buick Chevrolet Electric Hybrid PHEV buick velite

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.