2007 Chevrolet Tahoe on 2040-cars

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NHTSA approves hybrid rearview mirror display in Cadillac CT6, Bolt EV

The Chevy Bolt EV prototype doesn't just have a fancy new all-electric powertrain. Just outside the driver's line of sight is a newfangled rearview mirror, one that can turn into a screen that shows a moving image from the rear-facing camera. Speaking to NPR's Robert Siegel yesterday, Department of Transportation secretary Anthony Foxx said that NHTSA has now approved this type of mirror/screen for use in vehicles. According to a letter from NHTSA to General Motors, GM will likely use this Full Display Mirror first in the 2016 Cadillac CT6 before coming to the Bolt. In its letter to GM, NHTSA said that the Full Display Mirror will only qualify as a standard rearview mirror as long as there are normal side mirrors in place. In other words, don't expect to see cameras and screens replacing all the mirrors in a motor vehicle just yet. @AutoblogGreen @NPR - #NHTSA has OK'd GM rear-view system that can switch between mirror & camera views. pic.twitter.com/6CBeIit10v — Anthony Foxx (@SecretaryFoxx) February 22, 2016 The Full Display Mirror was developed by Gentex, which has long worked with GM. The FDM debuted in 2014 and some people hoped it would also make its way into the Tesla Model X. Gentex, which also makes auto-dimming mirrors, says that it has "set out to develop the technologies and core competencies necessary to manage this evolution of the rearview mirror." The Chevy Bolt EV will start at $37,500, before incentives. The 200-mile EV will go into production late this year for likely sale in early 2017. Related Video:

Hagerty kicks back with Ringbrothers for a look at the Recoil

Over the years, Ringbrothers has shown the ability to mix a meticulous eye for style and serious amounts of horsepower with customs like the Pantera-based Adrnln. The company's recent project, a tuned 1966 Chevrolet Chevelle called Recoil, is some of its best work yet and already has Jay Leno's denim-clad stamp of approval. Now, Hagerty is taking a look, while digging into the history of the actual Ring brothers: Mike and Jim. The two guys grew up in a small town where owning a car was practically a necessity, and the brothers were already wrenching before they could even legally drive. Eventually, that passion grew into a business, which led to wonderfully customized performance vehicles like the Recoil. Hagerty gets a fascinating look into Ringbrothers tuning philosophy in its interview. Of course, the real interest lies in this custom Chevelle, and there's a chance to hear the absolutely ferocious sound from the Recoil's supercharged V8 in this clip.

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.