Hey Mr X, l do not know if you're right, but l thought it may have something to do with 'Renn Sport ...'. Please help!

Really Super Roar,

It is the race version of the GT3 RS,and the RS stands for Rallye Sport,so as it is the race version l reckon the RSR is the Rallye Sport Racer.

Going back to 1973, & the original 911RS & RSR. the RS was was Rennsport (basically German for Motorsports). The RS was built in order to homologate the RSR (ie, must produce a certain number of street going version that the race version - the RSR - would be based on).

The situation is the same today, with the current GT3 RSR being homologated from the GT3 RS. Porsche has never mentioned that RSR stands for anything in particular, but it would most like be something along the likes of Rennsport Racing (slightly redundant, but it does need a different name than the one it is based on).

EDIT - the RSR version is available from Porsche. It is sold through their motorsports division & is the same car u see during ALMS races in the GT2 class (rouogh cost is a little more than $400k last l checked). The RS version is not a race car (though it is an excellent track car), it is a street car that is produced so that the RSR version qualifies as for the GT Class (likewise, the GT3 Cup race car is built from the basic GT3).

l do not believe an RSR version is available from Porsche. The race versions seem to be designated RS.

RS usually means Rally Sport. The other R could stand for Race.
Rally Sport Race.