Formerly the M3 and now the M4, BMW debuts a concept of the upcoming and iconic performance coupe at this year’s Concours d’Elegance bringing an aggressive new design, but still a Bimmer through and through. Muscular and streamlined, the car is just dripping in carbon fiber and aerodynamic upgrades including a carbon fiber roof, front splitter, and tailpipes. No word on the powertrain just yet, though we’ll be sure to get you updated look (and specs) when BMW unveils the production M4. Images of the M4 Concept are available after the jump.