So I want to grab some new 17" rims to replace my stock ones, running 16x6.5 +55 offset (I think) as stock with 5/114.3 stud pattern, yada yada yada and 205/50/16 tyres.

What I'm wondering is; what tyre size will I need for 17" rims at 7" width, and what is the maximum width/tyre combination I could run at stock suspension without stretched tyres.

Would be much appreciated, thanks.