Sierra RS Cosworth (1985-1986) have:
Front 283 mm vented disks
Rear 273 mm not vented disks

Sierra Cosworth 2WD (1988-1991) have:
Front 283 mm vented disks
Rear 273 mm not vented disks

Sierra Cosworth 4WD (1990-1992) have:
Front 278 mm vented disks
Rear 273 mm vented disks

Escort Cosworth T3 (1992-1994) have:
Front 273 mm vented disks
Rear 273 mm not vented disks

Escort Cosworth T25 (1994-1997) have:
Front 278 mm vented disks
Rear 273 mm vented disks

axles have some differences, their finish codes aint the same. but i think there are no major changes between them.