BMW's carbon-fiber roof has long been a hallmark of the brand's top performance cars, as it reduces mass and lowers the center of gravity. Now, BMW is expanding the feature to more mainstream models. Starting in March, the M Sport versions of the 3 Series sedan and 4 Series coupe will offer the option of a carbon roof panel — in Europe, at least.
Specifically, BMW will offer the feature on the turbo six-cylinder M340i xDrive and M440i xDrive as well as the diesel-powered M340d xDrive and M440d xDrive. BMW USA would not say whether our M340i xDrive and M440i xDrive would get the feature.
BMW has offered a carbon-fiber roof panel as far back as 2003, when it appeared on the ultra-exclusive E46-generation M3 CSL ("Coupe Sport Lightweight"). The carbon-fiber-reinforced roof panel was part of a comprehensive weight-saving effort that saw the track-day special shed 243 pounds compared to the regular M3.
With the arrival of the succeeding E92-generation M3, the carbon-fiber-reinforced roof panel became standard on the coupe (on models without the optional sunroof). The feature was expanded to the four-door M3 with the arrival of the E80 generation. Today, the CFRP roof is standard on the new M3 and M4, the M8 coupe and the M8 Gran Coupe, and the M5. It's optional on the M850i xDrive coupe and Gran Coupe. And, of course, the i3 features a carbon-fiber roof — part of its CFRP body cell.