2004 Bmw X3 2.5i Sport Utility 4-door 2.5l 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.

BMW i8 official images leak ahead of Frankfurt [w/video]

The new BMW i8 plug-in electric supercar isn't set to make its official debut until September 10, when it will glide onto the Frankfurt Motor Show stage amidst a sea of flash photography. Of course, that isn't so true in today's world, where debuts are always preceded (often carefully) by "leaks."
Take this trio of images of the BMW i8 - there's just enough of the exterior on display in the profile shot to draw attention, without showing important styling points that might be present on the front or back of the car. The same goes for the video attached below. The cabin shot is cool, but isn't particularly earth-shattering when it comes to BMW interiors. As for the skeletal shot, we can see the 1.5-liter, turbocharged engine positioned between the rear axles, the battery pack found in what would be the transmission tunnel and the front-mounted electric motors.
We'll have a full set of live images when the BMW i8 makes its debut in Frankfurt next week. Until then, have a look in the gallery and at the video below, and let us know what you think of BMW's next big thing.

A car writer's year in new vehicles [w/video]

Christmas is only a week away. The New Year is just around the corner. As 2014 draws to a close, I'm not the only one taking stock of the year that's we're almost shut of. Depending on who you are or what you do, the end of the year can bring to mind tax bills, school semesters or scheduling dental appointments. For me, for the last eight or nine years, at least a small part of this transitory time is occupied with recalling the cars I've driven over the preceding 12 months. Since I started writing about and reviewing cars in 2006, I've done an uneven job of tracking every vehicle I've been in, each year. Last year I made a resolution to be better about it, and the result is a spreadsheet with model names, dates, notes and some basic facts and figures. Armed with this basic data and a yen for year-end stories, I figured it would be interesting to parse the figures and quantify my year in cars in a way I'd never done before. The results are, well, they're a little bizarre, honestly. And I think they'll affect how I approach this gig in 2015. {C} My tally for the year is 68 cars, as of this writing. Before the calendar flips to 2015 it'll be as high as 73. Let me give you a tiny bit of background about how automotive journalists typically get cars to test. There are basically two pools of vehicles I drive on a regular basis: media fleet vehicles and those available on "first drive" programs. The latter group is pretty self-explanatory. Journalists are gathered in one location (sometimes local, sometimes far-flung) with a new model(s), there's usually a day of driving, then we report back to you with our impressions. Media fleet vehicles are different. These are distributed to publications and individual journalists far and wide, and the test period goes from a few days to a week or more. Whereas first drives almost always result in a piece of review content, fleet loans only sometimes do. Other times they serve to give context about brands, segments, technology and the like, to editors and writers. So, adding up the loans I've had out of the press fleet and things I've driven at events, my tally for the year is 68 cars, as of this writing. Before the calendar flips to 2015, it'll be as high as 73. At one of the buff books like Car and Driver or Motor Trend, reviewers might rotate through five cars a week, or more. I know that number sounds high, but as best I can tell, it's pretty average for the full-time professionals in this business.