[Norris83]

I never felt that my 2018 M550I brakes were lacking for everyday driving but they look small especially the rears with my 21" summer wheel/tires setup. I was tempted to buy the M performance brakes but found a good deal on a set of used front calipers and discs off a M850 which have 395x36mm discs.

For the rear brakes, if you have a 2020 M550I the rear discs are now 370x24mm vs 2017-2019 345x24mm. When I checked realoem parts, the only difference are the discs and the caliper carriers.

I could have purchased the rear calipers off the M850 but I don't think they would fit on G30. The m850I has 398x28mm rear discs not sure if the calipers would bolt up properly on the rear hub assembly.

Got all the parts on Friday April 23. Booked it at the shop for this Wednesday. The front EBC Redstuff brake pads have more contact surface vs the oem brembo pads. I also notice that in the middle they have a slot/opening. The rear caliper carrier brackets should work with the existing calipers by just extending the calipers further away to accommodate the larger 370x24mm rear discs. I also got stainless steel brake line hoses.