17" versus 14" tires

Seems to me the most common 17" tire for a Mustang is a 245/45R17. That's what I run, on '97(?) GT wheels. Works well, no rubbing on the fender or suspension. But I am running a Cobra rotor based BBK, so it is like I am running a small spacer, too.
2005 mustang GT stock tire size was 235/55R17, assuming it stayed that way through the end of that generation (2014)