a local guy had 335's on a 17x10.5 rear rim...IIRC he had no quads, aftermarket lowers and either tails or dumps.
I run a 17x11 and 315's and really dont see any reason to go wider...it looks almost cartoonish as is. A wider rim like 11in wide rim will give the 315's alittle more width over a 10.5 rim tire for tire. I have been asked if my 315's are 335's and they had to look at the tires to believe me.