Cuz it's easier to get a pair of rims with tires than to get 2pairs, get all if u have the $, but I dont so....i want to get 17s in the front too, bit tirerack dont recommemd, which means theres proly scrubbing, but 16 will fit with no prob. U know it's a big diff when u go from stock 15 to 17, right?no means to pay more to make 17s fit, but if it does, let me no wat u did. 215 should b gd enough even if u want a lot of grip.