2007 Chevrolet Express 2500 Base Standard Cargo Van 4-door 6.0l 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.

24 Hours of Le Mans live update part three

We tasked surfing journalist Rory Parker to watch this year's live stream of the 2016 24 Hours of Le Mans. What follows is an experiment to experience the world's greatest endurance race from the perspective of a motorsports novice. Parker lives in Hawaii and has an associates degree in dropping f-bombs. For Part One, click here. Part Two is here. Really hoped I'd be able to grab an hour or two of sleep before the sun rose over Le Mans. Dark dark dark, couldn't figure out what was going on. Commentators struggled at times as well. But I couldn't do it. Endurance racing is just too exciting. Grabs my attention with both fists. Screams, "watch these men DRIVE!" A neighbor invited me over for drinks. Told him, "Can't do it, gotta watch Le Mans!" Maybe not exactly. I'll admit, at times my attention wandered. I did a load of laundry. Ate some snacks. Half listened to the commentary. Threw a hump at my wife. I learned that Patrick Long, driving #88, is big brother to Kevin "Spanky" Long. Spanky's a bit of a legend in the skate world. Always weird how top notch talent can run in families like that. Kind of surprised I've never heard that before. Worked for a skate mag for a years, met Spanky a handful of times. Someone must've told me that he has an older brother who drives race cars. Dash cams at night are scary. High powered headlights in the P1s reach almost 300 meters. Cars outrun that distance easy. Seems like they're just steering into the black and hoping for the best. But that can't be the case. People'd be dropping dead let and right. Very amused by how the guys in GT are like, "Dude, stop flashing your fucking lights before you pass." But the LMP's are all, "Suck a dick! I do what I want." Top three stayed neck and neck nearly all night long. As the sun gets ready to creep back over the horizon the top three are separated by only eleven and a half seconds. Toyota 5 and 6, Porsche 2. Audi 8 is two laps behind Porsche, beleaguered 7 is dealing with constant trouble eleven laps from the front. GTE Pro sees Ferrari 82 in first, Ford 68 and 69 right behind. To win you've gotta drive perfect, build perfect. Fours cars retired so far. I'm beginning to appreciate the endurance aspect a little more fully. Only really considered the drivers at first. The mental and physical stress driving these cars at these speeds at length would inflict. But keeping the damn things running is the real deal. To win you've gotta drive perfect, build perfect.

2020 Chevrolet Tahoe, Suburban and GMC Yukon all spied with production lights

One of our spy photographers just caught a smattering of full-size GM SUVs out testing, including the Chevrolet Tahoe, Suburban and GMC Yukon. Previous spy photos of the next-generation of these big GM SUVs have revealed that GM is going with an independent rear suspension design, and these shots confirm the news once again with our best look at the hardware yet. Check them out from the rear, lined up like ducks in a row to see the beefy control arms down there. This will undoubtedly give the big SUVs a more compliant ride, and should bring it back into touch with the refinement from the Ford Expedition and Lincoln Navigator. The new bits we get to see with these shots are production headlights and taillights that are shaping up to look pretty neat. Most distinguishable are the GMC Yukon's LED DRLs. These look a lot like the C-shaped LEDs outlining the headlights on the Sierra, but they have an extra LED strip on top of the C. The parts of the taillights that we can see look significantly different than that found on the Sierra, showing GM is planning on having a great deal of differentiation there. We can sort of see through the mesh covering the grille to what appears to be a classic horizontal bar style front opening. Chevy is predictably dialing the crazy LED strip design back for the Tahoe and Suburban. The parts that are lit up look a whole lot like the headlight fixtures on the 2019 Silverado. That truck uses a stack of lights with the actual headlights separated from the DRLs. We can see the same thing going on here, with the headlight up top and curved LED DRL strip sitting below. It's tough to say if the designs are exactly alike, but we expect to see an extremely Silverado-esque look once all the camouflage comes off. Chevrolet's taillight design differs from its donor truck like the GMC, showing off a curved, vertical series of LEDs out back. Once production lights start popping up like this, we know the vehicle is moving closer to its end game. A reveal sometime later this year could be in the cards for GM's next batch of full-size SUVs. It certainly needs them quick, as Ford rockets ahead with increased Expedition production announced earlier this week.