17's Lowered HElp!

Hey, I'm looking into getting some 16/17 inch oz super leggeras
I've seen some pictures of del sols with them it looks awesome!

THe problem is, I'm going for mostly performance, I'm wondering
If i should do 17? See... the delema is.. If i got 16's the gap on the sides of the tires are too big for me. 17's look much better. I don't want to mess up abs and all that. also I want performance sooo. I don't want to mess up gear ratios too much
Here are some pictures of the gap which i'm talking about and the oz del sol