Hello, first time poster and Z owner. I have been thinking about putting some 225/50/16 Potenza RE 760 Sports on some 16x7 Rota Sa racing wheels. Id like to know what you guys think, and if I'll have any clearance problems. Pics below are my Z and the rims I'm interested in.

 

Provided you get them in an offset close to 0 or +10, you should have no problem with fitment. Anything more than about +18 will need spacers.