Those are 20'' Atech - not sure on backspacing as I don't pay too much attention to it unless its crazy. The tires are Yokohama AVS ST in 265-50-20 which I did not find on tirerack to post a link to. Atech are under a different name now, so I am told. I thin MB wheels maybe?

Honestly I am thinking of selling this set, but not sure how soon or if I will. I will probably make a thread here for opinions.