Hi peepz! Dont know if anyone can help me before i order my adapters for my porsche twists! I have 17" 7.5j on front and 9j on the rear. The front wheels im happy with a 20mm adapter but the rears i have a 225/45 tyre and with the old adapter which was 25mm it sat flush with the arches does anybody know if i would get away with a 20mm adapter on the rear just to give me more arch clearance so i can go lower but what i need to know is if i have a 20mm adapter will the inner tyre or rim hit the shock? opinions or previous experience would be great! the et on the rear wheels are et 47!