I've had no joy with either pad or calliper upgrades, although i do feel that the callipers are not the weakest link given they're Brembo's & are 8-pot fronts, so i'm now contimplating an upgrade for the discs. The new OEM pads i got fitted just before my recent track day at Combe, appeared to perform much better than the previous OEM pads, so perhaps the originals from new were just from a duff batch.
My question is about disc size & available options. I know the callipers are larger on the RS6 than the RS4, but are the disc sizes & fitments the same on both cars? AmD can do drilled discs (365mm fronts) for the RS4 at a much lower cost than Audi quote & these are Quattro GMBH origin so should perform well.
My local Audi dealer wanted £250 per corner

Any comments or advice will be gratefully received.
