1963 Ss Chevolet Impala 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.

GM warning 800,000 owners that their cars may need oil changes more frequently than they say

The days of changing your engine oil every 3,000 miles are long gone thanks to most cars having automatic oil monitoring systems, but about 800,000 General Motors vehicles apparently have incorrect monitoring software that is leading to premature engine component wear. According to Autoweek, certain 2010-2012 Buick LaCrosse, Regal, Chevrolet Equinox and GMC Terrain models equipped with 2.4-liter four-cylinder engines could be going too long in between oil changes resulting in a higher-than-normal number of warranty claims for the engine's balance chain. The balance chain links the balance shaft to the crankshaft, and a worn one can produce higher noise levels.
As a fix, GM dealers will be reprogramming the software for the monitors in an effort to reduce the interval between oil changes, which varies based on driving habits and conditions. Through February 2015, the software update will be done at no cost to vehicle owners, but since this is not a recall, after that point, it will be up to the discretion of dealers as to whether or not they will charge for the service. What isn't immediately clear is whether GM plans on giving assistance to out-of-warranty customers who are experiencing engine issues from the worn chain.

The real costs of keeping a Chevy Volt on the road

The release of the new, 2016 Chevy Volt is sure to bring a surge of used electric vehicles to the market as early adopters trade their older models in. Many of these cars are selling for a fraction of their original price, thanks in part to federal and state incentives that lowered the initial cost to the first owner, which opens these cars up to a whole new class of consumers. While the prices are getting attractive, potential buyers are still hesitant to buy a used EV due to uncertainty about service and repair costs, but there may be some good news on the horizon. The Chevy Volt comes with a battery warranty that is good for at least 8 years and 100,000 miles, but many of the Volts popping up on the market have passed that 100,000-mile mark. The threat of needing a new battery can be a deterrent, especially with some dealers quoting prices as high as $34,000 for a full "drive motor battery replacement." That sum is more than the MSRP of a 2016 model. Some of the fear of EV maintenance and repair comes from the mystery of the individual pieces that make up the drivetrain and charging system. If we take a look at the Volt in terms of analogs to a traditional internal-combustion vehicle, the outlook becomes a little more friendly. The Volt battery pack consists of three lithium-ion modules in a T-shaped arrangement, each of which can be serviced individually. Module 1 is made up of 90 cells and corresponds to GM part number 22954462, which retails for $3,258.33; module 2 is made up of 72 cells and corresponds to GM part number 22954463, which retails for $2,930.00; lastly, module 3 is made up of 125 cells and corresponds to GM part number 22954464, and retails for $4,933.33. These part numbers have been added to the dealer order systems but have not shown up in the distribution centers at this time. Although all three of the modules add up to a fairly large $11,121.66 total and are still on hold for dealer ordering, the good news is that in most cases these battery cell modules do not need to be replaced. There are many other individual pieces mounted on the battery pack that are serviceable, such as the Battery Energy Control Modules (BECM) and the Battery Interface Control Modules (BICM). These modules control and monitor the battery packs and charging system and have been known to fail while the lithium-ion battery cells are not at fault. Some have been replaced under warranty, but if you are stuck buying one they run about $255 a piece for the part.