1985 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.

'Faster. Farther.' dives into the history of Porsche racing tech

No doubt, Porsche has produced some of the best endurance racecars around, such as the turbocharged, slant-nose 935 of the 1970s and the ground-effects-enhanced 956 and 962 of the 1980s. But the company's most famous racecar, its first overall winner at the 24 Hours of Le Mans, was the 917.
The 917 embodied many of Porsche's technological achievements up to that point, such as the company's first 12- and 16-cylinder engines (the flat-16 was never used in competition), fiberglass bodies that implemented early aerodynamic practices and the use of new, exotic materials, such as magnesium and titanium.
The racecar was commissioned by the head of Porsche Motorsports, Ferdinand Piëch, to win overall at the 24 Hours of Le Mans in 1970, after he realized a loophole in the rules that allowed cars to compete with engines up to five liters in the Sport category if they were also production models. Piëch saw opportunity: the top prototype class was restricted to three liters; the production minimum to compete in Sport was 25 cars. And so, with much effort, Porsche assembled 25 "production" 4.5-liter 917s and had them parked in a neat line for the race inspectors to verify their legitimacy. It didn't take long before people realized the new Porsches were much faster than the prototype racers, with a top speed approaching 250 miles per hour.

Dodge Viper and Jaguar XK revival | Autoblog Podcast #543

On this week's Autoblog Podcast, Editor-in-Chief Greg Migliore is joined by Green Editor John Beltz Snyder and Consumer Editor Jeremy Korzeniewski. We talk the possible rebirth of the Dodge Viper and Jaguar XK, as well as the recent goings-on at Tesla. Then we share some of our experiences driving in Europe. We also discuss the cars we've been driving, and help spend another listener's hard-earned dough in this week's "Spend My Money" segment. Autoblog Podcast #543 Your browser does not support the audio element. Get The Podcast iTunes – Subscribe to the Autoblog Podcast in iTunes RSS – Add the Autoblog Podcast feed to your RSS aggregator MP3 – Download the MP3 directly Rundown Dodge Viper and Jaguar XK to make a return? Tesla Model 3 braking issues and Elon Musk vs. media Driving in Europe Cars we've been driving: Porsche Panamera Turbo S E-Hybrid Sport Turismo, Infiniti QX50, Range Rover Velar Spend my money Feedback Email – Podcast@Autoblog.com Review the show on iTunes Related Video: Auto News Green Podcasts Dodge Infiniti Jaguar Land Rover Porsche Tesla Car Buying Used Car Buying Driving Safety Performance jaguar xk infiniti qx50