The mysterious BMW M4 prototype wearing a MotoGP safety car livery has been spied undergoing testing on the Nürburgring.

The mysterious BMW M4 prototype wearing a MotoGP safety car livery has been spied undergoing testing on the Nürburgring.

There are rumors of a lightweight GTS version of the M4 Coupe slated to come out in 2016 and it seems BMW has already started testing procedures. The regular M4 tips the scales at 1,572 kg (3,465 lbs) whereas the GTS will reportedly weigh less than 1,400 kg (3,086 lbs) thanks to a more lightweight body and a stripped down interior cabin.

Set to become a proper track weapon, the BMW M4 GTS will also get an uprated suspension, fixed rear wing, a roll cage and bigger brakes. It could also turn out to be more powerful compared to the regular M4 which has 431 HP (317 kW) and 550 Nm (406 lb-ft) coming from an inline six 3.0-liter engine. These figures could be lifted to somewhere in the region of 450 HP (331 kW) and 600 Nm (442 lb-ft) which combined with the lighter body would make the M4 GTS a seriously fast car around any circuit.

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