Albino,
Wilwood makes several different brake pad compounds for various purposes. You may want to check out their catalog (link below).
http://www.wilwood.com/Pdf/Catalogs/BrakePadCatalog.pdf
Also, proper bedding of a new set of pads is important to insure good performance. I suspect that many people never properly bed their brake pads and that may have been the case on your car. Wilwood also has some good technical advice on their website for bedding brake pads.
Good luck
Ted