Just to share info. I'm reasonably sure this Wilwood set up is also available for the Focus, it's 13" making it 330mm I think....as fitted to my Fiesta:
My SVT Focus set up, not fancy calipers but they are more than up to any abuse I've thrown at them, 330mm fronts:
11.75 inch or 298mm rear with stock calipers relocated.
Both: