Dimensions and Construction

Though it bears little resemblance to a current 3-Series coupe, the 2014 BMW i8 will have about the same length and width as that premium-compact car, but will stride a slightly longer wheelbase and stand some 3.5 inches lower--just a little over 4-feet tall. It should also be some 100 pounds lighter, based on the concept's quoted curb weight of just under 3,270 pounds. Though the i8 will launch as a 2+2 coupe, with adult-size front seating and two smallish rear seats, Britain’s Autocar magazine reports that BMW is mulling a companion convertible with a lightweight fabric top.

The 2014 BMW i8 is claimed to have a 50/50 front/rear weight distribution, ever a must for this brand, along with rear-wheel drive and handling-oriented chassis tuning. The i8 maintains the tradition, thanks in part to a powertrain format unlike that of most any other hybrid seen to date. It involves a small aft-mounted gasoline engine, which drives the rear wheels through an automatic transmission (type not yet disclosed), and an electric motor in the nose, which provides front-wheel drive via a single-speed reduction gearbox. A plug-in lithium-ion battery pack nestles in a longitudinal cabin tunnel to spin the motor, an arrangement also used for the compact Chevrolet Volt range-extender hybrid sedan. Though the two i8 powerteams aren’t mechanically connected and function independently, they can be electronically deployed in tandem to provide de facto "through the road" all-wheel drive. A similar powertrain, but with key component differences, will highlight the Porsche 918 Spyder, a small 2-seat roadster expected for model-year 2014. Britain's Jaguar is prepping its own eco supercar based on the 2010 C-X75 Concept coupe; we expect it to materialize as the 2014 Jaguar XK200.

Like baby brother i3, the 2014 BMW i8 employs the automaker’s new weight-efficient construction concept called LifeDrive. This involves an upper "Life" module--meaning the passenger cell--and a lower "Drive" module or chassis that carries the two powertrains, battery array, suspension, steering and brakes. The sections are joined by just a few bolts and industrial-grade adhesives.

Perhaps the most significant aspect of the 2014 BMW i8 is making the Life module almost entirely of light-but-strong carbon-fiber-reinforced plastic, a first for a "mass market" vehicle. This particular CFRP was specially formulated in conjunction with the U.S. firm SGL Carbon, which will also supply the raw material from a new dedicated plant in Moses Lake, Washington that runs mostly on clean hydroelectric power.

Each i8 body is made up of several CFRP sections that are formed by a new low-cost BMW process. AsMotor Trend describes it, the procedure employs "six or eight layers of uni-directional carbon fiber that are stacked in a heated female mold; then the male mold closes, resin is injected, and the part cures in a couple minutes. This process is similar to the one used to produce the Lamborghini Aventador passenger tub" and the main structures of several other new exotic sports cars, "but the cycle times are quicker. Crash repair is said to be a simple matter of sawing out the damaged section and gluing in a [replacement]. Non-structural parts...are made using the short-fiber uncured trimmings left over from other operations, combed for some directional strength and cured to provide a class-A paintable finish." MTalso notes that the car’s "unstressed outer body panels are thermoplastic, but because they’re mounted to a carbon-fiber structure with similar thermal expansion characteristics, the [i8] should never suffer the wide panel gaps a steel-structured Saturn displays in the heat of summer."