Brake rotor size

[BigMacSmallFries]

Originally Posted by Boss330

Can't vouch for the accuracy, but in Auto Bild Sportscars Magazine (February 2014 edition) they have the following brake sizes listed in the spec sheet:

Steel brakes:
380mm front / 370mm rear

CCB:
400mm front / 380mm rear

CCB requires 19" wheels according to the BMW configurators that are online at the moment.

If that's the case, the callipers must have a compact design never seen before. A 380mm set up has never been able to fit in an 18" wheel in the past. Nice.

[Holset]

Originally Posted by Sedan_Clan

That's just it. No need for that! There are already kits in red, orange and yellow available alongside the blue.

How do you know the M-Performance is the same calipers as on the M3/M4? or do you just asume because they look alike?
I have looked at some pics to try to compare and they look similar but a bit hard to tell ,wonder if the pads are the same to if this is correct.
I think i would go for red calipers think they would look nice on a dark colored car.

[Sedan_Clan]

Originally Posted by Holset

How do you know the M-Performance is the same calipers as on the M3/M4? or do you just asume because they look alike?
I have looked at some pics to try to compare and they look similar but a bit hard to tell ,wonder if the pads are the same to if this is correct.
I think i would go for red calipers think they would look nice on a dark colored car.

They are the exact same Brembo developed calipers; the rotors are different (...and I'm sure the pads are a different compound as well).

[Holset]

Originally Posted by Sedan_Clan

They are the exact same Brembo developed calipers; the rotors are different (...and I'm sure the pads are a different compound as well).

Ok same in both front and back? Do you some partnummbers to compare?

[Boss330]

Originally Posted by BigMacSmallFries

If that's the case, the callipers must have a compact design never seen before. A 380mm set up has never been able to fit in an 18" wheel in the past. Nice.

I guess it's also a question of wheel design.

The std. F10 M5 brakes (at 400mm) fits with the std 19" wheels, but you cannot buy just any aftermarket 19" wheel and retrofit. You need a 20" aftermarket wheel to clear the brake caliper.

With a 380mm rotor and a 18" wheel there is a 38,6mm difference from 18" (457,2mm) and the 380mm rotor (457,2-380/2=38,6mm).

The wheel isn't 457,2mm on the inside though as you have to subtract the thickness of the material (see illustration below):



Material thicknes will vary according to material and manufacturing processes, but a 5mm thickness would not be impossible.

http://www.bbs-usa.com/bbs-technology-expertise.cfm

So subtracting 5mm from 38,6mm leaves us with 33,6mm. And then you need some air between the caliper and rim, which probably is at least 5-10mm. Ending up with a space of 23,6mm that the caliper can extend beyond the 380mm rotor.

So, as long as the caliper doesn't extend more than around 20-25mm above the rotor, there should be clearance...

[Gearhead999s]

Originally Posted by BigMacSmallFries

If that's the case, the callipers must have a compact design never seen before. A 380mm set up has never been able to fit in an 18" wheel in the past. Nice.

I run a 18x10 @ 25p with my Stoptech 380mm with no issues on my E92 M3.

[BigMacSmallFries]

Originally Posted by Gearhead999s

I run a 18x10 @ 25p with my Stoptech 380mm with no issues on my E92 M3.

Ok, so there's an exception to the rule but I bet you were warned that almost no 18" wheels would fit with those rotors on. I installed some winter 18s on the E92, there was around 3mm of clearance between the inside diameter and the calliper and those callipers are only 14.2". I can't imagine which wheels out there would possibly fit the 15" set.

[Brosef]

Originally Posted by BigMacSmallFries

If that's the case, the callipers must have a compact design never seen before. A 380mm set up has never been able to fit in an 18" wheel in the past. Nice.

Brembo 380mm in 18" wheels at Road America.

[Gearhead999s]

Originally Posted by BigMacSmallFries

Ok, so there's an exception to the rule but I bet you were warned that almost no 18" wheels would fit with those rotors on. I installed some winter 18s on the E92, there was around 3mm of clearance between the inside diameter and the calliper and those callipers are only 14.2". I can't imagine which wheels out there would possibly fit the 15" set.

I have 2 sets of 18x10's 25P that work with the 380mm's,a set of MT1's from tire rack and a set of Apex's which have much less clearance than the Mt's.The Brembos are 8mm larger than the the ST80's and have to be removed for pad changes unlike the ST's.

[Blacktan]

Can anyone tell me what is the offset distance of front and rear discs ?

[shwaara]

Hi guys, I have the 370/380 callipers and wanted to order 380mm rotors. However, somebody told me that 380mm are designed for M4 and will not fit the e89/e92 because of measure of the hole in the middle. e89/e92 allegedly fits only the 370mm M Perf rotors.

Has anybody researched / measured this? The local dealer doesn't know..

Thank you!