I think what '70CortinaGT' means is that the R1 discs 5/8 " thickness are cross-drilled which relieves some heat but are not the same as vented discs like the ones found on the Capri 2.8. These have a webbing between the friction surface of the discs and are approx. 1''.
i figured that.. i trying to do a volkswagen/volvo combination. passat rotor with a 240 4piston caliper, i'm trying to make something that will be easy to replace when brake job time comes around.. buying 2.8 vented rotors are a little too expensive for my taste.. the shipping cost almost twice as much as the parts..
Yeah , those would be the rubber tops. I think the person that told me said they work on the bearing mount to . Not sure , haven't had a bearing one apart yet .
well, i got the volkswagen rotors to mount to the cortina hubs, looks nice.. i'm in the process of mocking up the caliper bracket to attach the volvo calipers, looks like it might work well. will post up some more pictures soon.