The Porsche 911 RSR and its predecessor GT3 RSR, GT3 RS and GT3 R are a line of GT racing cars produced by Porsche that are used in motorsport for endurance races. They are based on the currently highest class in GT racing worldwide, the GTE class from ACO. These regulations lead back to the concept of a GT3 class below the then Group GT1 and GT2 from 1998. After the discontinuation of the GT1 class, the planned GT3 class was from 1999 at the ACO as a GT class below the GTS, as well advertised by the FIA from 2000 as N-GT. After the alignment of the GT rules between FIA and ACO in 2005, this class was renamed GT2 class. When the FIA's GT2 European Championship failed and the participants in the GT1 class at the 24 Hours of Le Mans dwindled, the ACO renamed the GT2 class GTE in 2011 and div