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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.

Chevy keeps teasing next Camaro, 70 percent of parts unique to it [w/video]

GM resumes production of its 3.0-liter turbodiesel straight-six

General Motors temporarily stopped taking orders for trucks and SUVs equipped with the 3.0-liter Duramax turbodiesel six-cylinder engine in August 2021 due to a supplier shortage. Reports claimed the pause would last through 2021, but the engine is already back in production. Enthusiast website GM Authority learned from sources inside General Motors that the straight-six is once again coming off the assembly line at the Flint Engine Plant in Flint, Michigan. There's no official word on precisely what the problem was linked to and whether it was related to the on-going chip shortage that's wreaking havoc across the automotive industry. All we know is that the pause lasted for about two weeks. Called LM2 internally, the six is available in Chevrolet's Tahoe, Suburban, and Silverado 1500 and in GMC's version of these trucks. It's also an option in the Cadillac Escalade. It develops 277 horsepower at 3,750 rpm and a V8-like 460 pound-feet of torque at 1,500 rpm in every application, and it allows these big behemoths to post surprising fuel economy numbers. Fitted to a rear-wheel-drive Tahoe, the Duramax returns 21 mpg in the city, 28 mpg on the highway, and 24 mpg in a combined cycle, figures that make it more efficient than a Blazer. Demand for the diesel-powered trucks is relatively high. While the shortage undoubtedly took a toll on sales, the Duramax represented 8% of Suburban sales and 6% of Tahoe sales in May 2021. There are no other diesel-burning full-size SUVs available new so they have the market to themselves. On the truck side, Ram still makes the EcoDiesel available on some 1500 trims but Ford abandoned the segment. Related Video: Featured Gallery 2021 Chevrolet Tahoe RST View 24 Photos Chevrolet GMC Truck SUV Diesel Vehicles