1986 Porsche 944 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.

The 2014 Rolex 24 at Daytona: What we learned, what we saw

Two days after the flag dropped on the 2014 Rolex 24 at Daytona, people are still trying to figure out what it might portend for the rest of the season. In 24 hours, two minutes and 24 seconds, 695 laps were completed by the car that crossed the line first. During that time, 67 cars began the race, 18 of them retired. There was that accident, and a red flag. There were supposedly slower classes beating supposedly faster classes. There were 16 caution periods, including that yellow flag. And then there was The Decision. And Then The Uproar. And then The Reversal.
There was also some pretty good racing, so let's have one last look at the weekend. Oh, and there was that 1964 Ferrari 250 GTO Series II...
If you want to skip the reading bits and go to the photos, there's a high-res gallery of 158 images above and a couple more below. Enjoy.

Here's what Jay Leno will be working on in 2016

Jay Leno always has a project or five underway in his garage, and since 2015 is practically over, his latest video offers a glimpse at some of the amazing vehicles we might see his team complete in the coming year. Leno's crew certainly has a lot to do next year. Leno's most impressive current undertaking is an effort to modernize a 1914 Detroit Electric with about ten times its original power output. He showed off the vintage EV as just a shell in his last tour of the garage, but his team has now recreated the wood body. They also started the project's bigger challenge of installing a new electric motor and lithium-ion batteries from a Nissan Leaf. If EVs don't interest you, Leno has plenty of other irons in the fire, too. There's a 1971 Porsche 911 that's under restoration to turn it into a solid driver and several motorcycles in various states of repair. Leno even welcomes viewers into his dyno room to check out the work on the Chrysler V8 for his Cunningham. The results of this wrenching and welding on these projects should make for even more compelling videos in 2016.