15X10 that is nuts! early single piston 944 calipers will work. The later turbo 4 piston only work with 16inch wheels to my best knowledge. 993 big red calipers will only work with 17inch wheels. Some mazda RX7's came with 4 piston calipers that fit under 15inch wheels. Question how did you widen your fuchs that much, re-weld or are they 3 piece? I have 15X8 fuchs in the rear and would like to give them some more backspacing and make them 15X9.