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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 faces possible class action lawsuit over 8-speed transmission

General Motors has been hit with a class-action lawsuit from owners who allege the eight-speed automatic transmission found in several rear-wheel-drive Chevrolet, Cadillac and GMC models between the 2015 and 2019 model years has a defect that causes the vehicles to hesitate and jerk when accelerating or slowing down. The lawsuit was posted to ClassAction.org and spotted by GM Authority. Problems with GM's Hydra-Matic 8L90 and 8L45 transmissions have been well-documented on Internet forums and via complaints filed with the National Highway Traffic Safety Administration, with many reporting damage to their vehicles. The lawsuit was first filed in December in U.S. District Court for the Southern District of Florida but appears to have been transferred recently to New York. Autoblog sought comment from Theodore Leopold, the lead attorney for the plaintiffs. "These transmissions have a common defect," the complaint reads. "Drivers attempting to accelerate or decelerate their cars feel a hesitation, followed by a significant shake, shudder, jerk, clunk, or 'hard shift' when the vehicle's automatic transmission changes gears." The problem also occurs when the vehicles accelerate in a single gear, without shifting, the plaintiffs allege. "Drivers have reported that the shift is sometimes so violent, they feel as though they have been hit by another vehicle." The problem is believed to center on the transmission, torque converter or both. The complaint says it causes undue friction, causing hydraulic systems and gears to function improperly and sometimes leaves metal shavings throughout the transmission, leading to costly repairs and replacement of parts or the entire transmission. It says GM has known about the problems since shortly after it introduced the transmissions, and has issued 13 technical service bulletins, none of which have resolved the problem. GM declined to comment on the lawsuit. The plaintiffs say GM should have warned consumers about the issues and covered repairs under each vehicle's three-year/36,000-mile bumper-to-bumper warranty. They're seeking statewide classes in at least six states: California, Florida, Illinois, New York, Oklahoma and Texas.

Corvette Stingray Convertible images mysteriously appear on web, so we add our own

It was inevitable that we'd see the 2014 Chevrolet Corvette Stingray topless at some point, but that didn't make us any less interested when a pair of supposedly leaked official images showed up on theautoinsiderblog.com last week. We posted them on our Facebook page, but held off reporting on them here until we could get a little more information.
Those images, which feature a dark red car on a sterile black studio background, supposedly first appeared on the website of diecast model maker Maisto. A Chevrolet spokesman has been reported saying that they are "not official images released by Chevrolet PR," which isn't a denial they're the real deal, but neither is it a confirmation.
Close examination of the photos suggest they could be official shots of the Corvette Stingray Convertible, and while some have doubted their authenticity due to a lack of vents (which were seen on the C7s that debuted in Detroit last week), it could be that the images are of a base model car without the Z51 package that doesn't require the extra venting and cooling.