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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.

The Corvette Museum sinkhole has been filled

After swallowing eight of the most prized pieces of the collection from the National Corvette Museum, the massive sinkhole from a year ago is rapidly becoming nothing but a bad memory. Based on the museum's weekly construction update, you can barely see the remnants of the 25-foot deep hole once in the floor. The Corvette Museum's Skydome was not always going to look like this. The original hope was to keep the sinkhole there as a tourist attraction. That plan eventually fell through, though, and instead it was decided five of the less-damaged Corvettes would remain unrestored. Progress has been moving fast to get the repairs done. Even a month ago, the hole was still very visible, and the construction company used remote-controlled Bobcat loaders to fill it in. Now, the museum has launched a contest to guess how many tons of stone it took to fill in the massive crater. The winner gets a print of the 2009 Corvette ZR1 Blue Devil being lifted out. Related Gallery National Corvette Museum Car Recovery View 25 Photos News Source: Corvettemuseum via YouTubeImage Credit: National Corvette Museum Weird Car News Chevrolet GM Videos National Corvette Museum

IIHS: High numbers of drivers treat partially automated cars as fully self-driving

WASHINGTON — Drivers using advanced driver assistance systems like Tesla Autopilot or General Motors Super Cruise often treat their vehicles as fully self-driving despite warnings, a new study has found. The Insurance Institute for Highway Safety (IIHS), an industry funded group that prods automakers to make safer vehicles, said on Tuesday a survey found regular users of Super Cruise, Nissan/Infiniti ProPILOT Assist and Tesla Autopilot "said they were more likely to perform non-driving-related activities like eating or texting while using their partial automation systems than while driving unassisted." The IIHS study of 600 active users found 53% of Super Cruise, 42% of Autopilot and 12% of ProPILOT Assist owners "said that they were comfortable treating their vehicles as fully self-driving." About 40% of users of Autopilot and Super Cruise — two systems with lockout features for failing to pay attention — reported systems had at some point switched off while they were driving and would not reactivate. "The big-picture message here is that the early adopters of these systems still have a poor understanding of the technologyÂ’s limits," said IIHS President David Harkey. The study comes as the National Highway Traffic Safety Administration (NHTSA) is scrutinizing Autopilot crashes. Since 2016, the NHTSA has opened 37 special investigations involving 18 deaths in crashes involving Tesla vehicles and where systems like Autopilot were suspected of use. Tesla did not respond to requests for comment. Tesla says Autopilot does not make vehicles autonomous and is intended for use with a fully attentive driver who is prepared to take over. GM, which in August said owners could use Super Cruise on 400,000 miles (643,740 km) of North American roads and plans to offer Super Cruise on 22 models by the end of 2023, did not immediately comment. IIHS said advertisements for Super Cruise focus on hands-free capabilities while Autopilot evokes the name used in passenger airplanes and "implies TeslaÂ’s system is more capable than it really is." IIHS in contrast noted ProPILOT Assist "suggests that itÂ’s an assistance feature, rather than a replacement for the driver." NHTSA and automakers say none of the systems make vehicles autonomous. Nissan said its name "is clearly communicating ProPILOT Assist as a system to aid the driver, and it requires hands-on operation.