As many already know, BMW will be dropping the 3-Series name for its future coupe and convertible models and using the 4-Series nomenclature as a replacement. We've already seen spy shots of the upcoming 4-Series Coupe, but now its convertible variant has also been caught testing. From these images we can see that the new drop top model will retain the same folding hardtop as the current 3-Series Convertible and will debut shortly after the Coupe.

The future 4-Series Convertible will utilize an engine line-up similar to that of the 3-Series sedan, meaning the latest four and six-cylinder petrol and diesel units in BMW's lineup. This includes the new 245bhp 2.0-liter four-cylinder petrol engine as well.

The 4-Series' design will borrow elements from the 5-Series->ke317 and 6-Series->ke320 models, but with larger, more squared-off headlights. The wide kidney grille will also have a 3D look to match that of the latest BMW models.

The BMW 4-Series Convertible will be revealed in 2013 and will be followed by an M version shortly thereafter.

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