lowered stang tire size?

I want to lower a 93 lx 5.0 with BBK springs. what is the biggest tire size I can use without the tires scraping?

Your lowering the car by 1.5". I have a 17inch rim on my 88 and there is a little rub at a certain angle with stock height. I figure 15-16" also your going to need to pick up polyurethane offset steering rack bushing kit to avoid bumpsteer.