BMW 1 Series sedan detailed

The engorged dimensions of the BMW 3 Series have been a source of enthusiasts' ire for years now. The 3er's growth isn't all that shy, especially of late: the sedan is 26.9 centimetres (10.6 inches) longer and 21 cm (8.3 inches) wider than it was in 1975, or for a more modern perspective, the brand new 3 Series is 16.5 cm (6.5 inches) longer than it was in 2002. It took 27 years to gain 10.4 cm (4.1 inches), but only 10 years to stretch another 16.5 cm (6.5 inches). To address the size and heft, a report in Autocar says BMW is planning a rear-wheel-drive 1 Series sedan to be "the spiritual successor to the E30-generation 3 Series four-door."

Talk of 1 Series models being spiritual successors to 3 Series models isn't new – part of the clamor around the 1 Series M was that it channeled the light flickability of the first M3s. A 1 Series sedan would serve three purposes: get a light, small, RWD model back in the lineup, give the company a clear competitor to the upcoming Audi A3 sedan and Mercedes-Benz CLA, and help BMW get closer to its sales target of two million cars in 2020.

The sedan would sit on a derivative of the platform used in the current 3 Series, and be different from the front-wheel-drive platform underpinning the forthcoming 1 Series GT. Four- and six-cylinder engines and BMWs xDrive AWD system are in the planning mix, as is an electric version. Autocar says 2015 is a potential sale date for the sedan, which would put it one year after the next-generation coupe and convertible officially bow.

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