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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.

GM natural gas-powered vans recalled due to possible leak

General Motors is recalling almost 3,200 of its compressed-natural-gas powered utility vans because of possible leaks. GM and the National Highway Traffic Safety Administration (NHTSA) released a notice last week saying that 3,196 Chevrolet Express and GMC Savana CNG vans are on recall, though no accidents have been reported due to the possible issue. The recall is specifically for vans for model years ranging from 2011 to 2014. The recall stems from a potential leak from the compressed natural gas high-pressure regulator, and such a leak could cause a fire or explosion. GM will replace the vehicles' high-pressure regulator in order to fix the problem, will do it free of charge and is instructing owners to contact Chevrolet or GMC customer service to arrange for the parts replacement. Utility vehicle makers like General Motors have pushed for fleet sales of CNG-powered vans and trucks for the past few years and have touted them for their cheaper refueling costs relative to standard gasoline, not to mention the fact that natural gas can be readily sourced from throughout North America (thanks, fracking). According to CNGPrices.com, compressed natural gas sells for about $2.22 a gallon, on average, while the AAA is pegging the average price of gas at $3.34 a gallon. NHTSA has posted information on the recall here. Featured Gallery News Source: NHTSA via Reuters Green Chevrolet GM GMC Natural Gas Vehicles CNG gmc savana

Next-gen Chevy Volt gets Corvette looks, adjustable regen levels

The hood may say "full speed ahead." The regenerative braking system says "slow down a bit." One person's automotive improvements is another's identity crisis, all in a day's work analyzing the new Chevrolet Volt. The next-generation version of General Motors' first extended-range plug in will include design touches taken from to the new Chevrolet Corvette, GM's iconic sports car. Hexagonal taillights and a "taut" hood will be part of the new package, Automotive News says, citing General Motors design chief Ed Wilbur. But does that mean the Volt is shedding any of its green-car cred? Not at all, if one considers that the Volt will also let the driver adjust the degree of regenerative braking using steering-wheel paddles to dial up and recapture as much energy as possible and engage in "one-pedal" driving or turn it down for easier coasting. Check out the 55-second video below featuring GM executives Mark Reuss and Andrew Farah trying out the Volt's new regenerative-braking system that was first used on the Cadillac ELR. GM will have more details for us when it unveils the 2016 Chevy Volt at the North American Auto Show in Detroit next month. The new version is said to have a larger battery, a longer all-electric driving range and more power, but Chevy's been fairly mum on those sorts of performance details so far. Green Chevrolet Electric volt cadillac elr corvette regenerative braking