Brake Disk Sizes

Most FR TDI have 255 mm rear brakes while all FR TFSI and some early (I think) FR TDI have 286 mm.

As far as I can see the fr tdi does indeed have smaller discs than the petrol fr, the calipers are different too. Unlike the description in the brochure............... I think the petrol fr is the same spec as a cupra on the rear?? 286mm anyhow.
Not sure why, but the dust shields look the same for both, which is why they look a little lost in the tdi fr

And facelifted FR TDI has 255 mm rear disks officially while FR TFSI still has 286 mm ones.