There’s not a lot to go on in these pictures of a highly graphic 3 Series BMW sedan undergoing some serious track testing, but word that the company is planning to move from V8 power back to a traditional inline six-cylinder engine for its next F30 M3 models continues to take root in the automotive gossip pages. Rife among the rumours of what the Bavarian company is planning for its next M3 is that it will apply as many as three turbochargers to give the inline six-cylinder a steady stream of power – although it has also been suggested the performance of its current TwinPower technology in various iterations may render such complication unnecessary.Supporters of the three-turbo theory are talking of a 3.3-litre capacity and an output of around 330kW (the current M3 has 309kW).What appears to be certain though is that the next M3 will be the subject of a lean and clean campaign bringing low fuel consumption and reined-back CO2 emissions, while delivering even more performance through a lightweight body using carbon fibre reinforced plastic (CFRP) technology. A TwinPower turbo six would also have no problem producing significantly more than the 400Nm of torque enjoyed in the current 4.0-litre V8 model.In these photos, no bonnet bugle is evident - as noted in previous articles - giving credence to the likelihood of a return to a six-cylinder M3. The next generation BMW M3 is expected to make its global debut in late 2012 or early 2013.