So, you want spacers with stock wheels, or aftermarket with different offset?

 

After market wheels with different offset to get flush fitment and possibly filling up some wheel well with some 40 series side wall tires.

 

On stock suspension the best fitment I've seen for being flush is 8J ET35, that was with a 225/40 tyre. With coilovers, camber and different tyre setups there are too many variable to give a definitive answer.

Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB - View Single Post - Tire fitment issues in the rear

The equivalent of 8J ET35 in different widths would be;
7.5J ET29
8.5J ET41
9J ET48*
9.5J ET54*

*Won't clear stock struts

 

I'm a bit biased but 17X9 +35 is pretty damn good. If you want to see some pics just check out my build thread. I'm running 245/40/17. If you want to have zero poke without camber 235 40 would be perfect.

 

Best flush fitment without changing camber and suspension is 18x8.5” +40
I’m really disappointed the 9.5” don’t fit without using excessive camber and stick stiff suspension. 9.5” would fit previous gen cars

 

what tire size with this?