One has to say that the Turbo´s weight is incredibly low if you compare it with its rivals, despite its AWD and steel chassis. The high torque numbers of the turbocharged engines demand solid and therefore heavy components as well.

The Ferrari might be the lightest, considering its level of equipment it could´ve well been even lower.

The AM, apart from being more GT than sportscar, certainly has its burden due to the heavy V12 engine. I also believe that the company is lacking ressources to significantly reduce the weight on the fly, this is probably due with the next modelchange.