are they 14's i take it, if so, then yeh go with 185 / 55 same as rs turbo;s
quite suprised they rub tho, as 15's go on ok with no prob and 15, would tend to run 195/45's.

But id def opt for the pad and disk change first before sheding out all that money on cossie breaks.

if you were going to get better breaks, ive been told on fiestaturbo.com that Zetec-s breaks go straight on, and you could just get a slighly bigger disk from say a st170 maybe.