I'm not sure if it can help you but this is what works for me:
I have 15 x 6 1/2 OZ wheels that are just perfect, with 195/50/15 and the offset is 40.
I tried 15 x 7 with a 35 offset, still in 195/50/15, they are too large, but if I use the low springs, they are just fine and look good.
But 205 wouldn't work on these, the strut is too close and also they would be out of the fender.
I think 35 is a limit, but offset is just one of the parameters.
I wouldn't try 17x7 on mine, I don't know how I could do, so maybe the turbo are different