Originally Posted by a burrito
I'm running 12/10 spacer combo on zcp wheels with a RD Sport drop. In the front with the spacers and a minor drop you will rub if you go any taller than the stock size. As for the rear 275/35 you may get away with if the tire you choose has skinny sidewalls and 295/30 will most likely have slight rubbing
It is absolutely impossible for your car to be rubbing with such a mild spacer setup and drop with stock sized tires.
I am lowered just as much as you with 18mm front and 15mm rear with no rubbing with a full car. I can actually do a 20mm front and 18/20mm rear and it won't rub.
I will be keeping the same spacers for the 255/275 combo. If I choose the 265/285 route, I will switch to a 15/12 setup.