1978 Silverado C-10 on 2040-cars

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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.

2014 Chevy Corvette Stingray order guide hits the web

The official debut of the 2014 Chevrolet Corvette Stingray is only part of the excitement for fans of Chevy's virtuoso sportscar. Although we got to see the car and some of its preliminary specs in Detroit and Geneva, there is still no word on pricing and some of the juicier data points we've been waiting for - such as confirmed power output, EPA estimated mileage figures and performance numbers. Until then, CorvetteBlogger has gotten its hands on the order guide for the coupe version of the car - in both base and Z51 iterations - revealing tidbits like standard and optional features and available color combinations.
Some other new details made it onto the order guide, such as our first interior specs for the coupe including slightly less hip room and headroom, more shoulder room and the same amount of legroom. To see the full order guide, head on over to CorvetteBlogger. From what we can gather, it sounds like more information will be revealed on April 25 during a party at the Corvette Museum, and for those sun worshipers patiently waiting for a convertible, it would appear you've got another model year to wait through.

GM recalls 83,572 SUVs for ignition switch issue

General Motors is recalling 83,572 SUVs from the 2011 and 2012 model years over a potential ignition lock actuator issue. In affected vehicles, the actuator isn't the right size, which could cause the ignition to get stuck in the "Start" position, and then either due to a jarring event or a "cool interior temperature" the ignition could switch back to the "Accessory" position. Doing so would cause a loss of power assistance and the airbags might not deploy. This is a different ignition issue than the one that's been ongoing for the past year. GM said it expects that less than 500 vehicles suffer from the problem, but that the pool could include vehicles from 2007 through to 2014 that have already been fixed, but with defective parts. The 2011-2012 SUVs included in the National Highway Traffic Safety Administration notice: Cadillac Escalade, Escalade ESV, Escalade EXT, Chevrolet Avalanche, Silverado HD, Silverado LD, Suburban, Tahoe, GMC Sierra LD, Sierra HD, Yukon, and Yukon XL vehicles. GM will notify owners and dealers will inspect the ignition lock housing to see if it needs a free replacement. RECALL Subject : Ignition Lock Actuator may Bind Report Receipt Date: DEC 30, 2014 NHTSA Campaign Number: 14V827000 Component(s): ELECTRICAL SYSTEM Manufacturer: General Motors LLC SUMMARY: General Motors LLC (GM) is recalling certain model year 2011-2012 Cadillac Escalade, Escalade ESV, Escalade EXT, Chevrolet Avalanche, Silverado HD, Silverado LD, Suburban, Tahoe, GMC Sierra LD, Sierra HD, Yukon, and Yukon XL vehicles. In the affected vehicles, the ignition lock actuator may bind, making turning the key difficult or causing the ignition to get stuck in the "Start" position. CONSEQUENCE: If stuck in the "Start" position, the ignition may suddenly snap back into the "Accessory" position, causing a loss of engine, steering, and braking power, increasing the risk of a vehicle crash. If the vehicle is in a crash, the air bags may not deploy, increasing the risk of occupant injury. REMEDY: GM will notify owners, and dealers will inspect and replace the ignition lock housing, as necessary, free of charge. The manufacturer has not yet provided a notification schedule. Owners may contact GM customer service at 1-800-458-8006 (Cadillac), 1-800-222-1020 (Chevrolet), or 1-800-462-8782 (GMC). GM's number for this recall is 14696 for the original equipment, and 14912 for the service replacement parts.