Just wanted to revive and old thread and see if anyone successfully fitted CTS-V calipers to e39m5
The e38 had optional brembo brakes? Which model specifically? I looked at the 750i, which is the heaviest and most powerful and I all I see are twin piston sliding calipers. Even if fixed caliper brembos were available on the e38, they would be incredibly difficult to find because I've never seen them.
Wow, of all things they put it into the 728i, but not the more powerful e38 versions like 740i and 750i. This doesn't make sense, but I guess that is what they did. A quick look at the rotors suggests that even if you can get the calipers, this is not a good option. Specifically, the 728i uses 316x28 rotors while our e39m5 has 345x32 rotors. So the diameter may be a problem, but even if that is solved, the new pads likely won't fit in since our rotor is too thick. I don't think that this e38 to e39m5 brake swap is worth pursuing.
Unless you get exceedingly lucky, or actually do the math, most of the time swapping calipers at random with another car is a downgrade in stopping distances (regardless of size, number of pistons, etc).
Guide to doing the math here, unless you are just after the bling and don't care about making your car worse:
How to Calculate Brake Bias - BMW M3 Forum.com (E30 M3 | E36 M3 | E46 M3 | E92 M3 | F80/X)