1976 Chevrolet C-10 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.

A Chevy Camaro hybrid? That's what EcoCAR3 could bring

Figuring out a way for a hybrid powertrain to co-exist with the performance expectations of a classic American muscle car is a challenge that could vex that most experienced of automotive engineers. It's a challenge, in fact, being handed to a bunch of college students. Over the next four years, students from 16 North American colleges and universities will attempt to wring fuel efficiency from a 2016 Chevy Camaro as part of EcoCAR3, an advanced-vehicle technology competition sponsored by the Department of Energy, General Motors and others. They'll be attempting to use hybrid or plug-in hybrid technology while not sacrificing the performance of the Camaro, which was selected in part because the current model achieves just 17 miles per gallon in city driving and 28 MPGs on the highway, per EPA numbers. Students will get the latest version of the vehicle to work on, one that is expected to be unveiled next month on Belle Isle in Detroit. "If we still want to produce V8 Camaros, we're going to have to look at alternative methods of propulsion," said Al Oppenheiser, the chief engineer on the Camaro. "So the ideas that these college teams come up with could very easily be adapted to a car like the Camaro." Unlike similar competitions that reward fuel efficiency in vehicles, EcoCAR seeks those gains while emphasizing cost and consumer acceptance of these vehicles. The cars shouldn't look like experiments; they should look like everyday vehicles on the road. Previous competitions have allowed the teams to use whatever powertrain they desired. This time, EcoCAR officials designed the competition to concentrate on hybrid, hybrid-electric and diesel options. Competitors won't have the option of using hydrogen fuel cells as they have in the past. Last year, a team from Colorado State built a vehicle that contained both hydrogen and electric power sources. This year's limit is a curious choice, as some automakers such as Toyota have placed heavy bets on fuel cells in recent years. General Motors also runs a fuel-cell program. With the focus on cost and practicality, however, the program officials wanted to narrow the framework of the contest. "We always have some good decisions on what to make within the scope or out of scope," said Jim Kolhoff, global director of software engineering for General Motors.

GM follows up Lambda CUV stop-sale with tire recall

In late January, General Motors announced a stop-sale for about 6,281 examples of the 2015 Chevrolet Traverse, GMC Acadia and Buick Enclave because of the possibility for the treads cracking on their 18-inch Goodyear Fortera HL tires. At the time, GM said that this would also eventually lead to a safety campaign to repair the problem, and the National Highway Traffic Safety Administration has just published those details. GM's recall covers 5,876 of the three Lambda platform crossovers to replace their tires. According to NHTSA, if the treads crack, there could be a loss of pressure and possible failure. Goodyear already announced its own recall of the tires after internal testing found small tread cracks. The company did not believe this was safety issue, but the problem did put the rubber out of compliance with federal laws. The business's safety campaign covered an estimated 48,512 tires. Of those, around 32,000 were reportedly made for GM to either be fitted to vehicles or sold as replacements. The remainder went to the aftermarket. Goodyear's portion of the recall is expected to begin around February 20. RECALL Subject : Tire Tread Cracking/FMVSS 110 Report Receipt Date: JAN 28, 2015 NHTSA Campaign Number: 15V044000 Component(s): TIRES Potential Number of Units Affected: 5,876 All Products Associated with this Recall Vehicle Make Model Model Year(s) BUICK ENCLAVE 2015 CHEVROLET TRAVERSE 2015 GMC ACADIA 2015 Details Manufacturer: General Motors LLC SUMMARY: General Motors LLC (GM) is recalling certain model year 2015 Buick Enclave vehicles manufactured December 9, 2014, to January 14, 2015, 2015 Chevrolet Traverse vehicles manufactured December 9, 2014, to January 20, 2015, and 2015 GMC Acadia vehicles manufactured December 9, 2014, to January 16, 2015, and all equipped with Goodyear P255/65R18 Fortera HL tires. These vehicles are equipped with tires that may experience tread cracking. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 110, "Tire Selection and Rims and Motor Home/Recreation Vehicle Trailer Load Carrying Capacity Information for Motor Vehicles with a GVWR of 4,536 kilograms (10,000 pounds) or Less." CONSEQUENCE: If the tire treads crack, a loss of tire pressure and possible tire failure may result, increasing the risk of a crash. REMEDY: GM will notify owners, and dealers will replace the tires that were manufactured within a specific date range, free of charge.