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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 looks to combat high theft rates on SUVs with added tech

The Cadillac Escalade has been at or near the top of most-stolen and insurance-loss lists for more than seven years, until it dropped to number six earlier this year. In 2011 it was fitted with a host of new security features to address its easy-to-override features and that has brought the number of thefts down, but when eight of the ten most stolen rides are large SUVs from General Motors, no one will argue that something else needs to be done.
Thus, GM has fitted this same theft-deterring tech to the 2015 Suburban, Tahoe and Yukon. The Suburban and Tahoe will get the steering lock that the Escalade and Yukon already get, plus bolted-down third-row seats to deter thefts like this, stronger door lock cylinders and shields, and side-cut keys to inhibit picking.
Additional security measures in a Theft Protection Package can be purchased for $395, consisting of sensors on the greenhouse glass and interior, an incline/tilt sensor and added "key control systems" to make it more difficult for the men in black balaclavas to steal what you bought.

Chevy up to old EVs-equal-range-anxiety tricks in new Volt Olympics ad

General Motors is at it again with a new Chevrolet Volt TV commercial. Viewers of the Winter Olymics (at least in some markets) recently saw a TV ad in between the skating and the skiing that made no mention of the environmental benefits or freedom from the power of Big Oil that electric vehicles provide. No, this one was based on pure survival instinct. In the video, a father is driving down a highway, perhaps through the Mojave Desert. His young son is sitting in the Volt's backseat and asks what happens when the EV's battery runs out. "We'll have to cross that burning desert with snakes and cactus until we make it back to civilization," the dad tells his son as they pass the skeleton of a fallen bull. The fine print makes it clear that the actual maximum range is 342 miles. But there is hope. The father tells his son, with a beaming smile on his face, that the gas generator has kicked in and they're going to make it through the desert. As they wend their way to the horizon, a voice over says that Volt drivers who charge up regularly are making it 900 miles between fill ups. The fine print makes it clear that the actual official maximum range before you need to either plug in or fill up is 342 miles. This theme that emphasized range anxiety has been utilized by GM since the extended range Volt was launched in late 2010, despite the fact that Chevrolet now offers an all-electric vehicle in the Spark EV. Volt fans are praising the commercial, called The New Freedom, on the GM-Volt forum and you can see for yourself below. This content is hosted by a third party. To view it, please update your privacy preferences. Manage Settings. News Source: Cheverolet via CleanTechnica, YouTube Green Chevrolet GM Fuel Efficiency Green Culture Electric range anxiety extended range