I currently have size 205 55r 16 tires on my Pontiac grand am 2003.

Try a 225/55-16

You can fit wider tires without too much problem, but a wider tire on a narrow wheel will have decreased stability. The more exaggerated the size the more it looses in lateral stability due to the thrust angle between the wheel lip and the tire sidewall.

You can fit wider tires without too much problem, but a wider tire on a narrow wheel will have decreased stability. The more exaggerated the size the more it looses in lateral stability due to the thrust angle between the wheel lip and the tire sidewall.