1968 Porsche 912 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.

Volkswagen may soon have remedy for more cheating diesels

Nearly a half-million motorists who own Volkswagens equipped with 2.0-liter engines have known for a few weeks the company might wind up buying back their vehicles as part of a settlement surrounding the company's emissions cheating. But about 85,000 drivers who own similarly afflicted diesels with 3.0-liter engines have been stuck without a remedy. They may not be waiting much longer. Bloomberg reports that Volkswagen will soon propose a fix for vehicles, including those from Audi and Porsche, equipped with 3.0-liter engines that will include new software and a new catalytic converter for the vehicles. Discussions with federal regulators are ongoing, according to the news outlet. "We are cooperating with the regulatory agencies and working with them on an approved solution," says Audi spokesperson Mark Clothier. "Beyond that, we cannot comment on ongoing investigations." Regulators have alleged that the company's 3.0-liter engines contain "defeat devices," illegal software that allows a vehicle to detect when it's undergoing an emissions test and turn off pollution control during real-world driving. The defeat device allows these vehicles to increase emissions of nitrogen oxide up to nine times the Environmental Protection Agency's allowable threshold. Affected 3.0-liter vehicles include the 2014 Volkswagen Toureg, 2015 Porsche Cayenne and the 2016 Audi A6 Quattro, A7 Quattro, A8, A8L and Q5. Volkswagen is slated to finalize its plans for buying back the afflicted 2.0-liter cars and potentially offer those motorists "substantial compensation" for their troubles by June 21, and it's possible that a formal announcement on the 3.0-liter vehicles would come at the same time. Related Video:

Porsche 911 Cabriolet refresh may hide new engine

If we learned nothing else from our recent frolic through Porsche's secret museum, it's that the automaker goes to incredible lengths to disguise future products during initial testing. Just as a number of cars in that Stuttgart bunker hid the true identity of developmental mules (like the Audi-V8-powered 911), such could very well be the case with these spy shots showing what, on the surface, appears to be simply a facelifted 991 911 Cabriolet.
Similar to what we saw last month on a 911 coupe, this Cabriolet has obvious styling modifications made to the front and rear fascias suggesting that the 911's still-fresh appearance is already set to get a few tweaks. The big news here is at the rear of the car. The additional vents on the lower edge of the fascia and the mocked-up vent above the engine leads our spy photographer to believe that a new engine could be tucked under the body work - likely a smaller-displacement, turbocharged flat-six focusing more on improving fuel efficiency and reducing exhaust emissions rather than performance.
We last heard rumblings of such a detuned 911 back in August, but could this be our first look at said new model? Have a look for yourself, and let us know what you think - either about this mule specifically or the idea of a "green" 911, in Comments below.