Drilled rotors are engineered to keep your brakes cool. Air flows over and through the drilled holes to effectively dissipate heat and eliminate hot spots. The drilled holes are precision machined in the Power Stop CNC machining centers. If you have ever experienced pulsating brakes and a shaking steering wheel, then drilled rotors are for you. Warped rotors are caused by excessive heat and the uneven deposition of friction. Power Stop drilled rotors run up to 180 degrees cooler and prevent warped rotors. All cross drilled rotors (Except Hub/Rotor Assemblies) are treated with a gold zinc dichromate finish to keep that new rotor look. The combination of drilled rotors and Power Stop brake pads will provide shorter stopping distance without fade.
While slotted rotors do not improve brake cooling, they provide a nice cleaning action to wipe away friction debris. On a standard rotor, brake dust and gas gets sandwiched between the pad and the rotor, and this can reduce pad bite. Independent tests show that slotted rotors actually do not improve the brake performance as much as drilled rotors, but they are more capable of handling severe thermal shock. Power Stop recommends slotted rotors for racing, and heavy duty applications like off road mud/trail driving. They also have a silver zinc dichromate finish (except for hub/rotor assemblies) to keep them looking good.
Power Stop Drilled and Slotted rotors combine the benefits of both the cross drilled and the slotted rotors. The cross drilled holes keep brake temperatures down. The slots wipe away brake dust and gas from between the pad and rotor. They look great installed on the vehicle, and they also have a silver zinc dichromate finish (except for hub/rotor assemblies) to keep them looking good over time.
Some Power Stop rotor are cryogenically treated. The 'Nitro Blast' cryogenic treatment process starts with gradually cooling the rotors to -300 degrees Fahrenheit over a 12 to 16 hour period in a liquid-nitrogen filled cryogenic processing machine. The 2nd step is to gradually ramp up the temperature back to room temperature. Usually, this cycle lasts for 8 to 14 hours. The 3rd step is the metal tempering phase - commonly referred to as heat treating. This process is very critical, if not done properly the entire cryogenic process will be mitigated. The cycle time for this phase usually lasts 3 hours and the temperatures can increase to as high as 1100 degrees Fahrenheit. The purpose of this step is improving the hardness of the newly formed primary martensite which will be brittle after the cryogenic phase. It must be properly tempered back to increase the hardness. When completed, the crystal microstructure of the metal has been altered to enhance wear, reduce abrasion, reduce stress risers and resist metal fatigue. Cryogenic treatment of rotors is recommended for severe duty vehicles, specifically race vehicles or fleet vehicles.
Power Stop Premium Brakes
Brake performance can vary greatly with different brands. Some aftermarket pads lose over 50% of the pad bite at high temperature or at high speeds. Over the past 15 years, Power Stop has developed the best performing brake pads in the business. Power Stop pads are used by premier installer shops throughout North America. The company has earned a reputation for OE quality friction, great stopping power, low dust, and noise free performance. Power Stop validates friction performance using stringent SAE (Society of Automotive Engineers) tests run by independent test labs. The following data shows braking power, noise and wear results for Evolution Ceramic compared with some popular aftermarket brands.
Noise Test Results using SAE J2521
Brake noise is caused by pad vibration. Power Stop pads feature dual layer rubber shims to dampen vibration and eliminate noise. Brake squeal can also occur if the backing plate is loose on the caliper guides. Power Stop uses precision stamped backing plates to assure good fitment to the caliper. The following chart shows the number of noisy stops for various aftermarket brands on the Chevy Tahoe. Compared to other brake pads, Power Stop pads are exceptionally quiet. Some "premium" aftermarket pads produce annoying brake squeal one out of every four stops. Power Stop ceramic pads will also keep your wheels cleaner.
The bottom line: Power Stop pads have OE level noise performance.
Brake performance is measured by mu, the coefficient of friction. Brake pads typically lose pad bite at high brake temperature or at high speed. This loss of stopping power is called brake fade. The next chart shows the minimum mu (pad bite) for some popular aftermarket brands. The higher the mu the more pad bite. The graph shows that Power Stop ceramic pads have significantly better pad bite and shorter stopping distance. The OE friction coefficient is normally above 0.30 even at 1500 degrees. Power Stop's minimum mu is 0.34. Some aftermarket brands lose more than 50% of the pad bite with mu around 0.15.
The bottom line: Power Stop has close to OE level performance for safer, faster stops.
Pad Wear The following chart shows pad wear during the ISO NWI 26867 test on the Chevy Tahoe. As you can see below, one brand lost 42% of the pad thickness. Most pads average about 10% to 13% wear during the test.
The bottom line: Power Stop pads have better than average wear characteristics.