In other words, the rims will be pushed outwards by about an inch, which may cause fender rubbing and accelerated ball joint and wheel bearing wear. Who knows, they just might fit, but I don't think it's going to function very well. But I do agree that if you were to do this, go with something like a 20", a 16" spinner with original size Potenza's would just look weird.
Of course, there's always the new spinner hubcaps like I saw on a Hyundai last night!!! That was a good 14" or so