Porterfield R4 Brake Pads have been used on our own racecars for over 5 years.  With extensive use in both our GT3 320i and World Challenge  328i Touring Car, these pads have proven to be a great success.   Porterfield pads feature:
- Carbon kevlar friction material 
- Provide excellent stopping power
- Extremely rotor friendly
- Excellent pedal feel 
- Immediate response to braking input
- Super high friction level through all temps
- Low wear rate