nell

I looked it up a while back and thought the size of the disc was smaller... When I tried to look it up again, the size for the non XI is not available. They do have different part numbers though. Whether that is a hub/flange difference or braking surface, I'm not sure...

The XI has 324x30 F and 320x20 R.

I would love to upgrade my XI brakes too.

545felix

i think you're going to run into a problem with either the rotor hat not being deep enough or the caliper bracket not holding the caliper at the right place. but the only way to find out is to try it.

now, if the Xi and 2wd cars have the same rotor part #s, caliper and bracket part#s, then you should be good to go. check same size engine cars in both Xi and 2wd on realoem to see.

nell

From another source, it looks like all the XI have different brake parts than non XI. The 535 XI and the earlier 528/530 XI uses the same size rotors.. The 2WD 535 and 550 shares the same size rotors. Quite a bit larger too. F 348x30 and R 345x24. That's about a full inch larger than the XI's. The M5 are another inch larger than that and thicker too.

545felix

the front rotors and caliper brackets cross reference the same on the 6 cyl non turbo cars (except the 525 manual, which has smaller rotors.) The caliper part #s, however, only show on the Xis, meaning the Xi calipers are the ones that factor in the extra offset. i don't think it's going to be doable.

M3This

Interesting. Thanks for all the info guys. I wish I could get my hands on some M5 brakes to test fit. If its strictly where the caliper mounts that can be fabricated, but if its an issue with the hubs that a whole new problem.

WorkE60

nice!