largest tire on 07 gt w/ 17" factory rims

Hey everybody. My 07 5 GT needs some new shoes. I'd like a bit more comfortable of a ride and I was wondering what larger sizes would fit on there? is 215/55r17 too big?


2011 MX5 GT
I had installed 215/50-17 on our 2008 Mazda5. OEM size is 205/50-17. While a 215/55-17 might fit, and it will be tight, I would think that is too big for the car.