dcanady1911

Does anyone know what size rotors omegas had and if there was more than one? Thanks in advance.

joe_padavano

What year Omega?

The 1973-74 cars used the same spindles and rotors as the 1969-72 A-body cars. Those rotors are 10.75" but most listings round that up to 11".
The 1975-79 cars used the same spindles and rotors as the 1970-81 F-body cars. Those are also 10.75" rotors (aka 11") but are not the same as the 73-74 rotors due to different wheel bearings.
The 1980-up FWD cars used 9.7" rotors.

dcanady1911

Thanks so much Joe, much appreciated. The reason for my asking is I attended the back to the 50’s car show in St.Paul Minnesota. There were two International Harvester pickups that had olds rally wheels on them. I was able to talk to one of the owners and he said it had a 1974 Omega from clip on it. That gentleman had 14” wheels on his truck, the other one had 15” wheels. I’m converting my 1970 cutlass to disc brakes and was pondering if they would fit within my 14” wheels. Thanks again for the information.

joe_padavano

I'm not sure what Omega rotors have to do with a 70 Cutlass, but the Cutlass came from the factory with disc brakes and 14" wheels. Understand that GM made two styles of 14" wheels - those that clear factory disc brakes and those that only clear drum brakes. In this photo, the disc brake wheel is on the left, the drum-only on the right. Outboard is to the left for both wheels. Note the shaping of the dropped portion of the disc brake rim on the backside to clear the calipers (yellow vs green arrow). This assumes your conversion uses factory 10.75" rotors, calipers, and brackets, or the repro equivalents.