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| We chose Performance Frictions high performance 2-Piece replacement rotors to give our M3 a mild performance upgrade. A cool features is the dimpled instead of drilled friction surface. You get the firebrand clearing of a drilled rotor without the risk of cracking. |
We wanted to upgrade to rotors of our M3 to some high performance parts. We were very impressed with what we saw at Performance Friction when we visited them a few months ago. So we selected some of their performance two piece OEM replacement floating rotors.
To see some of what we saw at Performance Friction click here!
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| The Performance Friction rotor is the same size as the stock rotor and is a high performance direct replacement for stock. |
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| The alloy hat makes the rotor weigh several pounds lighter than stock. This is both rotating and unsprung weight. The rotor is a narrow drive lug to reduce heat conduction to the hat and hub bearings. The rotor is held to the hat with high quality NAS hardware. |
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| The Performance Friction rotor has more internal fin area for better heat dissipation. It is also very precisely machined on all surfaces for near perfect balance and very little runout. |
Performance Friction makes a wide assortment of rotors from heavy duty stock replacement parts to racing applications so if you are redoing your brake system, they have some for you at every performance level you would need. All of Performance Friction’s rotors are not copies of the OEM rotors but reengineered to be better. The rotors are made of a special heat resistant and dimensionally stable at high heat, grade of iron. The rotor’s vents are reengineered with the vent locations and geometry determined by extensive airflow, stress and thermal analysis. The rotor axial and radial runout is closely controlled to a few ten thousandths of an inch to ensure nearly perfect balance.
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| The Performance Friction two piece rotor has a unique lug drive system that takes the shear loads of braking off of the retention hardware. |
Performance Friction’s two piece racing rotors besides being manufactured to extremely close tolerances have a few other unique features. The rotors are two piece and fully floated to reduce stress on the hats and the rotors themselves when hot. One piece rotors tend to want to warp into a cone shape under thermal stress due to the unequal thermal mass caused by the hub area. Making the rotor in two pieces with a friction ring free floating on a mounting hat eliminates this. Floating the rotors also reduces caliper piston knock back under spindle and hub bearing system flex which helps ensure a firm and consistent pedal. Since the mounting hat is made of lightweight aluminum alloy, the two piece floating rotor is significantly lighter as well.
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| Two piece rotors tend to rattle which some people may find offensive for street use. Performance Friction uses these leaf springs to take up the free play to reduce the rattle to make the rotors streetable. What a cool feature! |
A unique and innovative feature of the rotors is that the rotor to hat interface uses a lug system that takes the shear load off of the hat bolts and increases the bearing area so that the rotor float is freer from bind under brake torque load. The rotors are also dimpled instead of cross drilled. This gives the firebrand venting of a drilled rotor without the stress cracking that drilled rotors are plagued by.
