XLR8SN

To make it as simple as possible to hopefully help you out a little...what I was stating was based on my setup which is a Nismo 370Z dropped on Tanabe GF210 springs running 19X9.5 +22 and a 5mm spacer with the stock 245/35 19 tires (effectively making them +17)...on hard dips and in a turn with a bump...I will rub the inner clips a bit. The clips are slowly getting shaved...so thats how I know.

If you use coilovers...then you can drop the car lower and by virtue of the suspension characteristics with coilovers...it will create negative camber as you lower the car. That extra few degrees might make it possible for you to fit in lower offset rims assuming you choose to drop the car low enough to get the right amount of negative camber to clear. The OEM a-arms do not have adjustments for camber. The negative camber is "created" as you lower the car on coilovers. The a-arms (or suspension travel movement) have a parabolic effect going towards the center of the car as you lower it. Lower car=more negative camber by default.

The 9.5 +15 is +2mm lower in offset from mine currently. I would assume that you might rub here and there depending on the road and surface conditions. Assuming just drop springs. At stock height...it might not even travel that far to rub at all. With coilovers...you can drop it and clear no problem I would assume.

You could also just use a 235 tire to stretch a little to give you that couple mm's to clear until you get coilovers and/or adjustable a-arms as well. You could also get a fender roller and flare out the front fenders with it too after you move the fender clips.

As long as you are willing to make the needed adjustments to run your setup...almost anything can be made to fit in there....well...within reason of drive-ability.

Hope that helps a little bit more.