Joined: Feb 2011
Location: Western MA
With the front 8.5" wheel you can't go too wide. I'm guessing a 255/40/20 may be as far as you can go. The rear at 10" you will be able to run at least a 295/35/20. As JBert has suggested, AM must have a wheel/tire package that you can refer to.
2014 Shelby GT500:Delivered 4/3/13, Black/Black stripes/Black interior, SVT Track Package, SVT Performance Package, JLT Oil Seperator, FRPP Resonator Delete, Syntha Max blue air filter, Revan Racing shifter bushing, Michelin PSS tires, Lloyd GT500 mats, and yes the stock Shelby seats.