The Mintex 1144 is not usable on the track! I had them on my S1 and they are just a fast road pad. Completely faded away in just two laps. Extremely good pad for everyday use though. Mintex has the 1155 which is for thougher use, but I haven't heard much of it.
Invest in some good known track pads and new brake fluid. Discs are very secondary. The grooves and holes do very little in the end.