We’ve already seen disguised prototypes of BMW’s upcoming 4 Series coupe, including the range-topping M4 Coupe following the debut of the 4 Series Coupe concept at this year’s Detroit motor show.
Now BMW appears to be systematically removing the cladding from prototype versions of both the 4 Series Coupe, which will replaces the 3 Series Coupe in Europe within weeks before it arrives here around October, and the 4 Series Convertible that will follow next year.
Pictured here by Automedia almost fully undisguised for the first time, the new 4 Series Coupe and Convertible are based on BMW’s latest 3 Series sedan and will again slot into BMW’s sports line-up between the two-door 6 Series and 1 Series (which will in turn become the 2 Series).
The 4 Series range is also expected to grow to include a four-door Gran Coupe derivative, mirroring the 6 Series family by 2015.
Expect both 4 Series models to be larger than both the two-door 3 Series models they replace and the existing 3 Series sedan. At 4641mm, the M4 concept is 29mm longer than the outgoing car and its wheelbase is a significant 50mm longer, at 2819mm.
Naturally, BMW’s fourth-generation mid-size two-doors, which will continue to compete with German coupes and cabriolets like the Audi A5/S5/RS5 and Mercedes-Benz E-Class, will also ride on tauter suspension tune than the sedans upon which they’re based.
Unlike the outgoing E92 M3 Coupe, the top-shelf M4s should be powered by a 3.0-litre twin-turbo six that eclipses the performance of its predecessor’s 309kW/400Nm 4.0-litre V8.
Matched with a seven-speed dual-clutch automatic transmission, the rear-drive M4 should also better the M3’s 0-100km/h acceleration time of 4.8 seconds, thanks in part to the continuation of lightweight elements including a carbon-fibre reinforced polymer roof.
Lesser versions will run the same powerplants the BMW fits to the best of its 3 Series sedans, including the turbocharged 180kW/350Nm 2.0-litre four-cylinder engine from the 328i and the 225kW/400Nm twin-turbo 3.0-litre six from the 335i.
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