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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.

December sales for Chevy Volt, Nissan Leaf are what you expected

It was another month of as-expected sales for the two pioneering plug-in vehicles in the US. The Nissan Leaf is basically treading water and the new-generation Chevy Volt is getting back to old habits with a big increase in sales compared to where the car was last year. It wasn't a surprising month, but there wasn't any reason to expect a surprise. In fact, we don't suspect this trend to veer too far from where it's at right now until gas prices shoot up or Nissan introduces a new Leaf. Neither of those things is likely to happen any time soon. Let's start with the mediocre news. Nissan reported today that Leaf sales for December 2015 totaled 1,347 units. That's a 56.6-percent drop from where the Leaf was a year ago, and contributed to the all-electric vehicle's 42.8-percent drop in 2015 sales compared to 2014. This past year, 17,269 people bought Leafs, down from 30,200 who did so in 2014. The Volt sold 2,114 copies last month, bringing the plug-in hybrids 2015 total up to 15,393. That's an 18.1 percent drop from the 18,805 Volts sold in 2014. We shouldn't see the past year as a total flop for the Volt, though, since the much-improved second-generation model was introduced late in the year. In fact, if we just look at December 2015 and compare it to the last month of 2014, we see the Volt was able to post a 41.9-percent increase. It'll be quite fun to see where the Volt's numbers go in 2016. As you probably know, we'll have our complete wrap up of green car sales for you soon. Stay tuned. News Source: Nissan, Chevy Green Chevrolet Nissan Electric Hybrid ev sales

2022 Chevrolet Silverado LT Trail Boss adds 3.0-liter diesel option

Order books just opened for the 2022 Chevrolet Silverado, which, in case you hadn't heard, is almost unchanged compared to the 2021 Silverado. The overhauled Silverado and GMC Sierra that we caught in spy shots several times last year and were expected to launch this year have been delayed. Until that pickup gets here, Chevrolet and GMC will add "Limited" to the names of the Silverado and Sierra. Fleet guides for next year's truck show the official model name as Chevrolet Silverado 1500 LTD. There are a few interesting features coming next year, though, like the Multi-Flex tailgate joining the options list for Silverado HD trucks. GM Authority also reports that the 2022 Silverado LT Trail Boss adds the 3.0-liter oil-burner with 277 horsepower and 460 pound-feet of torque as a third engine option, which should be a big treat for the off-roading crew. Whereas the GMC Sierra AT4 already offers the 3.0-liter diesel, the Silverado LT Trail Boss only offers the 5.3-liter and 6.2-liter V8s, both bolted to GM's ten-speed automatic transmission. Then there's the Custom Trail Boss that adds the 4.3-liter V6 as an option, and it and the 5.3-liter V8 only get 6-speed automatics. At the moment, Silverado trims that offer the Duramax charge a $1,045 for it over the 5.3-liter V8. If that gap holds true for next year, the diesel will just about evenly split the price difference between the LT Trail Boss with the 5.3 and the 6.2.   Elsewhere in the range, Driving.ca said Canadian fleet guides show the 4.3-liter V6 and lower-spec 5.3-liter V8 with Active Fuel Management (AFM) instead of Dynamic Fuel Management (DFM) disappearing from next year's base Silverado WT. To clarify, AFM only shuts off half the cylinders in certain conditions, whereas DFM constantly adjusts how many cylinders are firing all the time. As it stands, that would leave the 2.7-liter turbo four-cylinder as the only engine option. However, those other two mills were the only ones left in the lineup that shift through a six-speed transmission, making it possible that they'll rejoin the options list with at least two more gears to choose from. It's not clear if GM will sell the Limited models alongside the majorly upgraded 2022 Silverado. The automaker did just that a few years ago, selling the previous-gen truck as a Limited trim alongside the then-new, current-gen. It certainly wouldn't be the only company to do so, either.