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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 seatbelt recall affects over 1m Silverados and Sierras

The Basics: General Motors will recall 895,232 examples of the 2014-2015 Chevrolet Silverado and GMC Sierra 1500 pickups in the US. The campaign will also affect the trucks in markets worldwide, and the total number the company will recall is 1,037,982. The Problem: A steel cable connects the seatbelt to the vehicle, but over time repeated bending can cause the part to fatigue and separate. Injuries/Deaths: None reported. The Fix: Dealers will enlarge the side shield opening and install a pusher bracket on the tensioner. Technicians will also replace the entire tensioner assembly if necessary. If You Own One: GM will contact owners about the recall. The company hasn't said when those notifications would begin. More Information: There are still about 3,000 new examples of these older pickups at dealerships. Until mechanics fix the problem, these vehicles are subject to a stop-sale. Similar problems have affected the General's vehicles in the past. In 2015, the company recalled over 400,000 units of the 2011-2012 Chevrolet Malibu for fatiguing cables. It also hit over a million Lambda platform crossovers in 2014. GM Recalling Certain 2014-15 Pickups to Repair Seat Belts DETROIT – GM is voluntarily recalling 895,232 model year 2014-15 Chevrolet Silverado and GMC Sierra 1500 pickups in the United States because the flexible steel cable that connects the seat belt to the vehicle can fatigue and separate over time as a result of the driver repeatedly bending the cable when entering the seat. This issue was discovered through warranty data, and there have been no reports of crashes, injuries or fatalities related to this issue. For trucks in the field, dealers will enlarge the side shield opening, install a pusher bracket on the tensioner, and if necessary, replace the tensioner assembly. The recall in the United States includes a stop-sale of approximately 3,000 new 2014 and 2015 model year pickups still on dealer lots. Dealers will repair the vehicles prior to delivering them to customers. Customers will be notified by General Motors. They also can look up their vehicle identification number (VIN) at either https://vinrcl.safercar.gov/vin/ website or at https://my.gm.com/web/portal/ownercenter to see if their vehicle is part of the recall. GM also will voluntarily recall and repair these models in other countries where they are sold, including Canada, Mexico, and several countries in Latin America and the Middle East.

Performance cars overpower the Detroit Auto Show

At precisely the stroke of noon on Monday, the 2016 Acura NSX rolled on stage at the Detroit Auto Show amid plumes of smoke and dancing lights. The sounds of the powerful engine revving soared to the rafters. It was the second coming of Acura's iconic sports car, and the reveal had all of the expected trappings. Afterwards, champagne corks popped and the bubbly flowed. It was noon in Detroit, but for the green-car movement, it seemed like the clock had struck midnight. That's an exaggeration, but performance was the overwhelming theme of North America's most important show. Ford – which has helped lead the way in smaller displacement engines and early adoption of hybrid powertrains – had more than 1,500 horsepower on stage one point after it revealed the GT concept, the new F-150 Raptor and the Shelby Mustang GT350R. The NSX is technically a hybrid (it has three electric motors), but with 550-plus hp, there's no doubt this Acura was bred on the track. The theme continued throughout the show at nearly every stand. Alfa Romeo showed off the 4C Spider, which is the open-air version of a car that purports to be the spiritual successor of the high-performance 33 Stradale from 1967. On Tuesday, Cadillac is scheduled to reveal the 640-hp CTS-V with the V8 transplanted from the Corvette Z06, and the Lexus was expected to roll out its own V8-powered beast, the 467-hp GS F. For enthusiasts – especially enthusiasts with money – these are halcyon days. But make no mistake, all of this power has a purpose. Ford product chief Raj Nair said the Blue Oval uses high performance cars to develop technologies, like aerodynamics and materials, which are then shared across its lineup. "It's another proof point about how serious we are in developing innovation through performance," he said. Ford, which is rolling out at least 12 performance cars by 2020, said the sporty cars attract younger and more influential buyers to its fold, which can help burnish its image beyond adding sales volume. Toyota is taking a similar approach, senior vice president Bob Carter said, noting the Lexus RC coupe draws people into showrooms and gets them excited about the brand, even if they don't end up buying one. "They provide an aspiration and a halo that provides the attention that gets you noticed in a cluttered market," he said.