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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.

2015 Chevy Volt gets larger battery, though range remains the same

The Chevrolet Volt isn't changing much for the 2015 model year. According to specifications uncovered by Inside EVs, though, the new Volt's battery does have a slightly larger capacity. According to the spec sheet, this doesn't translate to increased range. Real world driving, though, might tell a different story. The 2015 Volt's battery storage is slightly higher than the outgoing model's, up from 16.5 kilowatt-hours to 17.1 kWh. According to GM's manager of electrification technology communications, Kevin Kelly, speaking to Green Car Reports, the increased capacity is "a late change done in the cell... just another continuous improvement to surprise and delight our customers." The stated electric range, however, stays at 38 miles. Inside EVs followed up on its original report, and found that drivers could see some advantage to the battery tweak. When they spoke to Kelly, he told them, "As a result of this change, we would expect that some customers may see a slight improvement in overall EV range." It's worth noting that when battery capacity increased from 16 kWh to 16.5 kWh for the 2013 Volt, electric range increased by three miles to the current 38, while MPGe went from 94 to 98. The price of the 2015 Chevrolet Volt remains steady, at $34,995. The actual cost to the customer is considerably less with the $7,500 federal tax credit, as well as any local incentives.