why not bite the bullet and do what im doing. upgrade to 280mm discs.
mk2 16v hubs, caplipers and carriers off a vr6, g60 or audi sport, then the g60 discs... bolt it all up, much betetr pads for the track, and not too expensive.
that coupled with decent pads, some braided hoselines, a 22mm master cylinder and some decent fluid, and your away! or stopping shouuld i say.
the bigger discs will cope with the racing heat generated from braking, will disperse is quicker, hence increasing max braking performance longer and increasing time until fade occurs.