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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 recalling 70k Chevy Malibus, Pontiac G6s over steering issue

A problem with the power steering system in the Chevy Malibu and Pontiac G6 has prompted General Motors and the National Highway Traffic Safety Administration to issue a recall for an estimated 69,633 vehicles. The issue revolves around the electric power steering assist, which could suddenly fail and increase the risk of a crash, especially at low speeds where the power steering is most helpful. The recall affects 2006-2007 Chevy Malibu sedans and Malibu Maxx wagons (specifically those manufactured between April 1, 2006, and June 30, 2006), as well as the Pontiac G6 (which was offered as a sedan, coupe or convertible) from the same model years and manufactured from April 18, 2006, to June 30, 2006. Owners of the affected units can expect to hear from the manufacturer with instructions to bring in their vehicles to their local dealers to have the torque sensors in the power steering system replaced. RECALL Subject : Sudden Loss of Electric Power Steering , 1 INVESTIGATION(S) Report Receipt Date: FEB 04, 2015 NHTSA Campaign Number: 15V064000 Component(s): STEERING Potential Number of Units Affected: 69,633 Manufacturer: General Motors LLC SUMMARY: General Motors LLC (GM) is recalling certain model year 2006-2007 Chevrolet Malibu and Malibu Maxx vehicles manufactured April 1, 2006, to June 30, 2006, and 2006-2007 Pontiac G6 vehicles manufactured April 18, 2006, to June 30, 2006. In the affected vehicles, there may be a sudden loss of electric power steering (EPS) assist that could occur at any time while driving. CONSEQUENCE: If power steering assist is lost, greater driver effort would be required to steer the vehicle at low speeds, increasing the risk of a crash. REMEDY: GM will notify owners, and dealers will replace the torque sensor assembly, free of charge. The manufacturer has not yet provided a notification schedule. Owners may contact Chevrolet customer service at 1-800-222-1020 or Pontiac customer service at 1-800-762-2737. GM's number for this recall is 14772. Note: This is an expansion of recall 14V-153 to cover additional vehicles built between April 1, 2006 and June 30, 2006. NOTES: Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.safercar.gov.

NHTSA closes book on Ford, GM probes of 600,000 vehicles

US safety regulators have closed a pair of investigations into some 500,000 Ford Crown Victoria, Mercury Grand Marquis and Marauder sedans built between 2004 to 2007, and 100,000 Chevrolet Impala models from 2014. The Ford investigation focused on rusting heat shields, which may become dislodged and jam the steering, according to Reuters. The National Highway Traffic Safety Administration found that this happened very rarely. In fact, of the ten incidents filed with the government safety watchdog, six came from a single police department, which evidently had some sort of problem with its reporting. As for the Impala, the NHTSA investigators attributed two incidences of "unintended autonomous braking" to user error. In both cases, the vehicles were involved in rear-end collisions. According to GM investigators, it's believed that drivers accidentally activated the electric parking brake, causing the collisions. The vehicles in question were rental cars. Featured Gallery Ford Crown Victoria Related Gallery 2014 Chevrolet Impala View 10 Photos News Source: ReutersImage Credit: Ford, Chevrolet Government/Legal Chevrolet Ford Safety Sedan ford crown victoria mercury grand marquis