[BRZ21]

I have a few questions

I'm looking to get Enkei Kojin 18 x 8.5 et45 front and 18 x 9.5 et45 rear
I'll be running stock suspension for the time being to stay in my autocross class (i'll be switching to stock wheels for c street)

for tires I was thinking 235/45 for the front and 255/40 for the rear
The reason I want these sizes is to get as much sidewall as possible to fill the wheel gap

So i have two questions (hopefully someone can answer):
1. Will these wheels fit with out hitting the stock springs?
2. The overall diameter of the two tires will be off by 7mm (1/4''). Will this effect abs/tc?
3. Will those tires sizes look silly?
thanks guys