BMW M3 (E46) 3.2 FRONT CROSS DRILLED KINETIX SPORTS PERFORMANCE BRAKE DISCS PAIR Brake Disc Thickness: 28mm Brake Disc Minimum Thickness: 26.4mm Brake Disc Centering Diameter: 79mm Brake Disc Height: 52.5mm Brake Disc diameter: 325mm Brake Type: Vented Brake Style: Drilled Only Drilled Only: Brake gas build up is a major problem when braking at high speeds which effectively causes brake fade. The drilled disc surface on the kinetix brake discs dissipate heat more effectively by breaking down surface gases more efficiently. The holes are laser drilled through the discs which reduce brake mass. The drilled brake discs also benefit from keeping braking temperatures rapidly low which helps keep the pad surface from reaching high temperatures that can be caused .
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