There's a dual
problem with the Brembo discs and pads. The Brembo discs are cast in one piece, cooled in a controlled manner (sprue) & heat treated. This leaves the metal inside softer, with the grain structure that's needed only on the surface and to an as best possible depth. The
problem with the metal core'd OEM Brembo pads is the degree of heat that builds up on the 4 metal cores through the pad. The heat transferred when stationary with the brakes applied (a bigger
problem with DSG cars, as of the lazy stop start driving they lend themselves to with thee foot on the brake pedal, as opposed to going into neutral & applying the hand brake) causes hot spots to form, readjusting the grain structure slightly each time and softening the metal. This can occur over the full circle of the disc on particularly heavy, long driving sessions, like track days of 'private country road' use. That's how the warping of the discs & groove wearing occurs. Seat were changing discs & pads like there's no tomorrow on the Nurburgring when setting the lap times for the hatch & ST (
280 ST still the 'ring estate car lap record holder). The aftermarket pads from Tarox strada pads are one piece, no metal cores (I think the corsa are too, but a harder compound). This won't entirely solve the
problem, but should diminish it somewhat. The Tarox discs are cut from billet, with the proper grain structure the whole way through them. They're joined to the rotor. That manufacturing method is much more preferable for a brake disc. They will last much longer with the use of a one piece pad with no cores, and would last longer with the Brembo pads too, but they'd still do those discs no good. I'm going to see how the discs look when the pad wear light comes on the next time round to see if I'm gong to bite the bullet and get the Tarox ones or if I can, hopefully get a second set of pads out of one set of discs. The Brembo discs have shot up in price over the last lot of months anyway, so they may be a false economy?