I agree with you on the pads, swap for Ferodo DS's! As for the master cylinder I'll have to disagree, the cosworth master cylinder isn't that much bigger. Does it still have ABS? My bet is that the ABS is the issue, it's jsut restricting the flow, eithrer that or the rear load compensators.

I know exactly what you mean about them not braking as you think they would, mine is exactly th same, I still have ABS and the load compensators, will be removing them and just running with a bias valve when I get round to it.

Lee