1996 Chevrolet Caprice Classic; Impala 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.

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.

GM's MPG overstatement could affect 2 million vehicles

Late last week, GM admitted that three of its large SUVs fuel economy window stickers did not match their actual efficiency ratings, and so the vehicles couldn't be sold. The stickers on the 2016 Chevy Traverse, GMC Acadia, and Buick Enclave said their ratings were one to two miles per gallon better than they should have been. Officially, the number of affected vehicles sits at about 60,000. But Consumer Reports makes a good point: what's up with all of the previous model year SUVs that are basically the same vehicle? To wit: the 2016 model year vehicles are not substantially different than the 2015 or the 2014, or even going all the way back to 2007. On the EPA's fuel economy website, all of these older models will "have better stated fuel economy numbers than the new vehicles in GM's dealerships," Consumer Reports noted. CR's best point, and the one that makes the 60,000 number potentially grow to 2 million if all of the vehicles built on this platform are affected, is that "[i]t seems unlikely that the company would change the powertrain on these carryover models so late in their model cycles in a way that would cause a dramatic, negative impact on fuel economy." GM says that earlier model year SUVs are not affected and the EPA did not respond to CR's question about the potential for more discrepancies. We've seen automakers reverse course before, so if GM has to come out with a mea culpa soon, don't be surprised. GM is rushing corrected stickers to dealers so that the SUVs can be sold again, but a fix for the already-sold vehicles could be trickier to solve. Related Video: Related Gallery 2013 GMC Acadia View 16 Photos News Source: Consumer Reports Government/Legal Green Buick Chevrolet GMC Fuel Efficiency mpg gmc acadia chevy traverse