1998 Bmw Z3 Roadster Convertible 2-door 1.9l on 2040-cars

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BMW i3 REx rated at 117 MPGe, 39 mpg with 72-mile EV range

The numbers haven't made their digital way to the EPA's website yet, but we can now confirm that the BMW i3 with range extender will be officially rated at a combined 117 MPGe with 39 mpg once the battery runs out. That puts the amazing little city car just ahead of the pure-electric Fiat 500e (116 MPGE, combined) and behind the Honda Fit EV (118) and the Chevy Spark EV (119). In the plug-in hybrid category, it's at the top of the class, beating out the Honda Accord PHEV, which is rated at 115 MPGe but is also a much bigger vehicle. The i3 REx also has an official all-electric range of 72 miles and can go another 78 on gas (for a total of 150). When it's not carrying around the extra fuel tank and engine, the all-electric i3 gets 124 MPGe (combined), which is the currently the highest in the US. The i3 EV also has an all-electric range of 81 miles. BMW expects to deliver the first i3 REx in the US this week and delivered the first all-electric version earlier this month. There was a bit of a hold-up on the range-extender version thanks to a delay with getting these EPA numbers. Now that all the bureaucratic boxes have been checked, it's off to customer driveways they go.

Researchers halfway to cutting carbon fiber costs by 90%

Carbon fiber has been utilized for decades to build racecars, as a means to cut weight while maintaining strength. But until recently, the space-age material has been largely absent from the street on anything but supercars because of the expense to use it. Recently, BMW signaled a major shift in that trend when it starting using carbon fiber reinforced plastic panels on the i3 and i8. This relatively small scale start might be just the beginning; the German company believes that a breakthrough to inexpensively manufacture the lightweight stuff is just on the horizon.
MAI Carbon Cluster Management GmbH counts BMW, Audi, Airbus, the German government and many other organizations as supporters, and it's researching how to make carbon fiber cheaper to produce, according to Automotive News Europe. The company thinks it can reduce costs by 90 percent in the near future. "We've certainly reached a halfway point on our cost-cutting target for suitable carbon-fiber parts," said project head Klaus Drechsler to Automotive News Europe.
Unfortunately, it isn't entirely clear just what MAI Carbon is doing to make such a huge leap possible. However, a recent post on the company's website talks about a new form a carbon fiber using a thermoplastic matrix that could be cured in less than three minutes. That's compared to about 90 minutes in the traditional process with an autoclave.

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.