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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: Houston's bus revival, autonomous trucks on the Autobahn

A documentary shows how Houston, Texas significantly improved its outdated bus system. Called High Frequency: Why Houston is Back on the Bus, the short film describes how the city reimagined its bus system to become more efficient, more useful and more popular. Despite some opposition, the change has proven to be effective, with bus ridership up eight percent in three months, and light rail ridership up due to complementary bus routes. See the video above, and read more at CityLab. Automakers sent autonomous semi trucks on the German Autobahn as part of the European Truck Platooning Challenge of 2016. Mercedes-Benz, Volvo and Scania, among other groups, sent platoons of trucks between Stuttgart, Germany, and Rotterdam, Holland. In Mercedes's platoon of three trucks, the lead truck was fitted with lasers and other sensors to guide the convoy down the road. The two following trucks relied on vehicle-to-vehicle communication to trail 50 feet behind the lead, making room for cars to come between them and closing the gaps when able. The close following distance provides fuel economy gains of up to 10 percent in the rearward trucks on account of the reduction in drag. Read more at Hybrid Cars. Renault has reduced NOx emissions in its Euro 6b diesel vehicles in real world driving conditions. By improving its exhaust gas recirculation systems and NOx traps, nitrogen oxide emissions are cut in half on average, under certain driving conditions. The improvements will be included in vehicles leaving the factory beginning in July of 2016. Beginning in October, owners of Renault Euro 6b diesels can have the modifications added to their cars for free. Read more from Renault. Tata Technologies is creating an innovation lab in California to partner with EV technology companies. Having a tech center in California allows Tata to work on technologies that will largely be deployed in the company's main market of Asia. "Today, we are partnering with companies and startups who have aspirations to sell in China, but a lot of what they do is in California," says Samir Yajnik of Tata Technologies. Read more from The Economic Times. BMW's i Ventures is investing in mobility-as-a-service software provider RideCell. RideCell provides technology for services such as carsharing, ridesharing and other transit services. "The convergence of transportation trends in cities is of key importance to BMW," says Ulrich Quay, head of BMW i Ventures.

Recharge Wrap-up: VW Golf TDI wins green car award, DC buses might go electric

The 2015 Volkswagen Golf TDI has won the award for 2014 Northwest Green Car or the Year. The distinction comes from the Northwest Automotive Press Association during its Drive Revolution event in Portland. Co-chairman of the event, Jeff Zurschmeide, says, "Volkswagen has led the diesel passenger car market for years, and the Golf TDI proves that they're likely to stay on top for a while." The 2015 Golf TDI has 10 more horsepower than the outgoing model, while improving fuel economy thanks to a new engine. It also has a base price $3,000 lower than the 2014 Golf TDI. Read more in the press release below. The BMW i8 gets its laser high-beam headlights from lighting company Osram. The laser lights use half the energy of their LED counterparts, according to BMW, which is important when one is trying to get every last bit of range out of the car's battery. The laser high beams can also reach about twice as far as LED lighting. Because of their brightness, they won't be available on cars sold in the US. In laser-equipped i8s, the laser high beams will not work below 60 kilometers per hour, nor when other lights are detected in front of the vehicle. Head to Automotive News Europe to read more. Renault has delivered a fleet of 30 Kangoo ZEs to Uruguay's government-owned power company, UTE. The electric fleet will allow the company to reduce its CO2 emissions by 36 metric tons, says Renault. 84 percent of Uruguay's electricity comes from renewable sources, with a goal of 90 percent on the horizon. Uruguay aims to get a third of its electricity from wind farms by 2016, meaning these Kangoo ZEs will be powered in no small part by renewable energy. For Renault, "This order is a further sign of the interest in the region for electric vehicles," according to Denis Barbier, Renault's senior vice president, citing previous deliveries in Brazil, Mexico, Argentina and Colombia. Read more in the press release at Renault's website. Washington DC's "Circulator" bus routes may go electric. Some of the diesel buses, which were first put to work in 2003, are nearing the end of their life cycle, and DC sees an opportunity to make the switch to something a little greener. "Electric has not been a viable option in previous procurements, but now it is," says Will Handsfield, Georgetown Business Improvement District's transportation director. Handsfield is concerned about air quality, and says he also appreciates the long-term stability of electric rates compared to diesel.