I am thinking 10.5 is the practical limit for rear wheels 
And here is why:
I know a rim manufacturer who does makes 20x11's for the Challenger in several types and other sizes, and they claim the 20x11 fits under the rear fenders and does not rub when on the car (though I imagine with two people, full fuel, and a trunk full of luggage hitting bumps I don't know-some folks can live with that type of rubbing but I can't on a $70K car) .
Further, if you put it on a lift it will contact the frame as the suspension relaxes. I am guessing if you push the 11 inch rim (offset?) to just outside the rear fender, this could be eliminated, but I am not a fan of that particular look at all and it of course brings the possibility of fender strikes.
The big problem is you can't really return them if you don't like them, lol.
Further, I love the factory rims-and spending a small fortune for rims of the same quality and not raising the weight significantly for just over 1 inch per rim (over the 9.5's) for the rear seems just not worth it to me?
Now if someone made the exact matching factory rear hellcat rims in 10.5's with no ill issues, I would be all over it. And sorry, rim widening is not an option for me.
So I feel I must wait or stick with the factories...
And here is why:
I know a rim manufacturer who does makes 20x11's for the Challenger in several types and other sizes, and they claim the 20x11 fits under the rear fenders and does not rub when on the car (though I imagine with two people, full fuel, and a trunk full of luggage hitting bumps I don't know-some folks can live with that type of rubbing but I can't on a $70K car) .
Further, if you put it on a lift it will contact the frame as the suspension relaxes. I am guessing if you push the 11 inch rim (offset?) to just outside the rear fender, this could be eliminated, but I am not a fan of that particular look at all and it of course brings the possibility of fender strikes.
The big problem is you can't really return them if you don't like them, lol.
Further, I love the factory rims-and spending a small fortune for rims of the same quality and not raising the weight significantly for just over 1 inch per rim (over the 9.5's) for the rear seems just not worth it to me?
Now if someone made the exact matching factory rear hellcat rims in 10.5's with no ill issues, I would be all over it. And sorry, rim widening is not an option for me.
So I feel I must wait or stick with the factories...