Cleaning Brake Rotors
Slots are slots. It seems...
Slots are slots. It seems that every rotor company has its own version of slots. I've never noticed that the shape makes a whole lot of difference.
Very few people take the time to clean or wash a rotor before installing it on the car. Washing a brake rotor with hot soapy water can remove bits of metal that might otherwise end up embedded in the new pads. I finish this washing process with brake clean. If I rub a white paper towel on the rotor surface and dirt shows on the towel, the rotor isn't clean enough.
Break in New Brake Rotors
Some people call it rotor seasoning. I call it a break-in procedure. Gradually heating the brake rotor means that the crystalline matrix will reconfigure to relieve internal stresses. After these stresses are relieved the rotor is ready to accept the heat of normal braking. Heating the rotors before they're fully seasoned can result in material deformation due to the unrelieved internal stresses in the material. This deformation can cause a vibration from the brakes.
Find a safe location where you can bring your brakes up to operating temperature. The goal is to gradually increase brake temperatures with progressively faster stops. Start by performing four 60- to 70-mph stops. Do this the same way you would normally drive around town. Next, perform four medium-effort partial stops from 60 mph down to 15. Follow this with five minutes of driving with little to no braking to allow the rotors to cool.
The important item in this...
The important item in this picture is the temperature strip on the caliper. This will give you an accurate reading of how hot your calipers are getting. The caliper temperature is a better indicator of brake fluid temperature than the rotor temperature.
Now perform four medium-hard-effort partial stops (about 75 percent) from 60 mph down to 15. Once again, follow this with 10 minutes of driving with little to no braking to cool the rotors. Now park the car and allow the brakes to cool overnight. You're almost done with the rotor bedding procedure.
On the next day, go back to your safe location where the brakes can be brought up to temperature. Once the brakes are warmed to normal operating temperature, perform four medium-effort partial stops from 60 mph down to 15. Follow this with five minutes of freeway driving with little to no braking to cool the rotors. Now make four medium to hard partial stops from 60 mph down to 15. Follow this with 10 minutes of freeway driving with little to no braking to cool the rotors.
Finally, make six hard partial stops from 60-plus mph down to 15 mph or until the rotors have reached an operating temperature of between 900 and 1,100 degrees F. If your Corvette doesn't have ABS, try to do this without locking a wheel. Follow this with 10 minutes of driving with little to no braking to cool the rotors.
This is a very basic C3 vintage...
This is a very basic C3 vintage brake system. The four-piston calipers work just fine if you keep fresh fluid in the hydraulic system and modern friction material in the calipers.
One final note for those of you who run track events. Rotors need to be gradually elevated to operating temperatures before any severe use. Use the first lap of a session to warm the brakes as well as the engine, transmission, and tires.
When you come off the racetrack at the end of your session, drive around the pit area a couple of times to let your rotors cool. Race cars are normally placed on jack stands, or the air jacks are used, to get the same cooling effect. At track events, slowly doing a couple of laps around the pit area works nicely. Also, never use the parking brake at a track event. If you normally use the parking brake, put some duct tape on the handle to remind you not to use it at the track. The last thing you need to do is place a red-hot brake pad against a red-hot brake rotor.
Check Rotor Quality
Compare the thickness of the rotor plates to an OE or premium-quality rotor. If you really want to have fun, weigh the cheap rotor on a scale and compare it with a known high quality brake rotor. If the weight and plate thickness are significantly below the OE or a premium-quality rotor, buy a different rotor.
Measure run out in the rotor and wheel bearing with a dial indicator. On most vehicles, lateral run out greater than 0.002 inch will generate a pedal pulsation problem. Also, check the thickness of the rotor with a micrometer. The minimum thickness will be cast into the rotor.
Even solid brake rotors crack....
Even solid brake rotors crack. That's how hot things get under racing conditions. This is a stock C5 brake rotor. The small cracks came from normal racing, but the rotor finally decided it had had enough. You'll probably hear a crack this big as you apply the brakes. This is why you need to inspect your brake rotors between every session. This applies to those of you who run track days, too. You're braking just as hard as a racer brakes.
C4 Grand Sport wheels are...
C4 Grand Sport wheels are very popular as race wheels. One reason is that the open spoke design allows the hot air from braking an easy exit.
The idea is to direct the...
The idea is to direct the air into the center of the brake rotor. This hot air then exits through the rotor vanes and into the atmosphere.