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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.

Recharge Wrap-up: Range-extended EV taxis in London, 2016 Chevy Volt interior two years old

The first Metrocab range-extended EV taxis are operating on the streets of London. The cabs use a 12.2-kWh battery and two 50-kW motors, as well as a 1.0-liter gasoline range extender. Fuel economy is 98 MPGe on the ECE101 cycle, and total driving range is over 348 miles before needing to charge or refuel. Cabbies can expect to save GBP20 to GBP40 (about $30 to $60) per day on average. "The cash savings on fuel are significant, the ride and comfort outstanding, and my first customers are thrilled with the new cab," says the first operator of the new EV taxi, Preston Morris. "With its air suspension providing unrivaled comfort, panoramic glass roof for views of the city and silent powertrain, what's not to like?" Read more in the press release below. Chevrolet has had the interior design of the 2016 Volt finished for two years already, according to GM interior designer John McDougall. Beginning around 2010, GM received sketches from designers worldwide before narrowing it down to a handful of designs. Then the top three choices were molded from clay. The chosen theme was then refined for up to 18 months. "Every little thing you can imagine goes into that," says McDougall. "The glare angle from the windows, the placement of the controls, the placement of the seat. You have to create something that's beautiful and functional." Read more at GM Authority and at Inside EVs. More details have emerged about the Second Life Batteries Alliance. Vattenfall has announced a research project in partnership with BMW and Bosch to use retired EV batteries for stationary, grid-connected energy storage in Hamburg, Germany. Over 100 lithium-ion batteries from BMW i3 and ActiveE vehicles will make up a two-mWh storage unit for grid balancing, enough to power 30 four-person households for a week. The system is "compact enough to fit in a small building," says Bosch. Such storage systems are especially fit for storing and moving alternative forms of energy, which often fluctuate in supply more than electricity from a traditional power plant. Vattenhall will operate the storage unit for 10 years, with Bosch managing the batteries, during which time the three partners hope to learn more about battery applications and their performance over time. Read more at Green Car Congress, or in the press release below.

GM to idle car production at five factories as Americans continue CUV love affair

In case you needed another reminder that Americans have fallen out of love with sedans, General Motors today announced plans to idle five factories in January in a bid to cut its inventory to 70 days. Detroit-Hamtramck Assembly ( Buick LaCrosse, Cadillac CT6, Chevrolet Volt and Impala) and Fairfax Assembly in Kansas ( Chevy Malibu) will stop production for three weeks. Lansing Grand River ( Cadillac ATS and CTS, and Chevy Camaro) is going down for two weeks, while Lordstown, OH ( Chevy Cruze) and Bowling Green, KY ( Chevy Corvette) will go idle for a week each, Automotive News reports. GM's shutdown reflects a broader problem with the company's supply – at 847,000 vehicles, the company's supply increased unsteadily from a low of 629,000 units in January of 2016. That's more than a 25 percent increase in the past year. Citing information from Autodata, The Detroit News reports that at the end of November, GM had a 168-day supply of LaCrosses, 177 days' worth of Camaro, 170 days of Corvette, 121 days for Cruze, 119 days for ATS, 132 days for CTS, and 110 days of CT6. Meanwhile, inventory of the company's more popular vehicles is actually below the professionally accepted 60- to 70-day supply, The News reports. The Trax, Colorado pickup, and GM's full-size SUVs are sitting below 50 days and experiencing year-over-year sales increases. GM needs a rethink of its inventory levels, which is something that's apparently coming. "We're going to be responsible in managing our inventory levels," GM spokesman Jim Cain told The News. Another unnamed spokesman told Automotive News the company's day-to-day supplies would "fluctuate before moderating at year-end." But at least one analyst thinks this won't be the last time Detroit needs to stop production to level things out. "Incentives are elevated, residuals are declining, and rates are rising," Brian Johnson, an analyst with Barclays, told The News. "And while GM in particular may benefit in the months ahead from new product launches, it's important to recognize that GM's inventory is elevated at the moment, and it wouldn't surprise us if they need to announce another production cut – which could pressure the stock." Related Video: News Source: The Detroit News, Automotive News - sub. req.Image Credit: Paul Sancya / AP Plants/Manufacturing Buick Cadillac Chevrolet GM GMC Crossover SUV Sedan bowling green cadillac xt6 fairfax