Does anyone know if the BMW brakes that are on the V6 are off a specific BMW model. I know a lot of parts are the same/similar to the E46, but anyone have anything specifics?
How much pitting is too much on the actual brake caliper? I have stripped one back that was almost a block of rust, and although its come up nice there is some pitting on it. It's hard to tell just how much as the finish on them is quite rough! The internals are spotless, just the exterior. I Imagine they must be ok otherwise they would manufacture them out of something that was so quick to rust.
I looked at the 330D but the piston sizes were different, I was trying to work out if they were a part made by BMW for the 75 specifically, or I just haven't found the right car
BMW wouldn't have made the brakes anyway. From memory I seem to remember the ones on the standard cars were made by ATE. That's especially true given the 190s didn't come along until after BMW had parted company with MGR.
Edit:
ATE do list the calipers, including for the 190. They are remanufactured, but I can't see them remanufacturing them if they didn't make them in the first place.
Couldn't find a BMW cross reference for it though.
Planning is an unnatural process, much better to just get on with things, that way failure comes as a complete surprise instead of being preceeded by a period of worry and doubt
They have BMW stamped on them but all the ones fitted to BMW's are different to the 190. I saw the ones listed by ATE Duncan as you can get replacement pistons but not the caliper from new as you say.