How big of a tire can I put on my 2014 mustang gt premium with the brembo brakes package? I know that they are 19 inch rims, but i don't know what the width of the rim is. I've hear 8.5 inch and 9 inch, does anyone know? I also have the 255 40 R 19 tires on them now, and wanted to put wider tires in the rear. So if you know, what size could I go with and if you have done it are there any problems or recommendations you would make?