Audi brake calliper “nub”?

[liner33]

Spotted this “nub” on an Audi recently anyone know what purpose it has ?

[colin_p]

Could it be a mounting point for an, as yet to be fitted, next Euro emissions (brake dust) recovery system?

[poppopbangbang]

Looks like a mass damper to me, if so there's probably one at the bottom too and likely inline with the caliper mounting points to the upright. It's used to change the resonant frequency of the assembly to avoid the brakes squealing/vibrating. Can quite often be seen on pads too for the same reasons.

[liner33]

poppopbangbang said:

Looks like a mass damper to me, if so there's probably one at the bottom too and likely inline with the caliper mounting points to the upright. It's used to change the resonant frequency of the assembly to avoid the brakes squealing/vibrating. Can quite often be seen on pads too for the same reasons.

That was my thoughts but i have never seen one before on a performance brake , maybe that's why Brembo's squeak

[stevieturbo]

Looks like a generic casting with radial mounting bosses on both sides of the caliper....but not used for the outside obviously.

eg

[Dave Brand]

stevieturbo said:

Looks like a generic casting with radial mounting bosses on both sides of the caliper....but not used for the outside obviously.

Makes sense to me!