That car only featured trim differences, though. The GTR we're meant to see at the Geneva Motor Show in March is rumored to have more power, be around 220 pounds lighter, and get new bodywork, particularly in the rear where P1 themes can be found including open bodywork that allows views of powertrain internals. According to a translation of the Autovisie article, "McLaren's design boss Frank Stephenson has been allowed to let off steam." Motor Authority says it could get a Long Tail option, a la the F1 GTR Long Tail. The Dutch report additionally states that it won't carry the name 650S.
Almost a year ago McLaren gave hints about the range of 650S racing models it was preparing. This rumored GTR sounds harder than the 650S Sprint (pictured) but we'll have to wait until March to see where it fits in with the GT3 model and the ghost of the 12C Can-Am Edition.