Are most drilled and slotted rotors directional?
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I may be missing something, but I did the searches and didn't come up with much. I recently installed drilled and slotted rotors on my '96 sc4 with brand new EBC green pads and immediately my brakes were squeeking like mad. I've since broken them in and driven over 1000 miles and they still squeeked. I switched *** around and it seemed to get much better. What I'm worried about is that I have heard that if rotors are directional and you install them the wrong way that they won't work nearly as well as they should. In general, should the slots and holes swoop forward or backward at the top? I apologize if this has been covered or if it is just common knowledge. Thank you in advance and I would appreciate hearing your opinions
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#4
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Here, take a look at this thread and you'll see how they should be. If you have any more questions, just ask. Hope this helps you out.
Jeremy
https://www.clublexus.com/forums/sho...5&pagenumber=3
Jeremy
https://www.clublexus.com/forums/sho...5&pagenumber=3
Last edited by jeremyp111; 05-26-04 at 07:47 AM.
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Thanks again. Now I gotta figure out why, since I had them installed correctly the first time, they were squeeking so bad. Maybe I'll get them turned and see what happens
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#7
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Originally posted by jeremyp111
Yes, they are directional and should swoop towards the rear at the top.
Yes, they are directional and should swoop towards the rear at the top.
BUT, here is my StopTechs (installed by StopTech) on my driver side where it is the reverse:
Endless (driver):
![](https://www.clublexus.com/gallery/data/500/7957img_1437-med.jpg)
APs (passenger):
![](https://www.clublexus.com/gallery/data/500/7957IMG_2451-med.jpg)
It really depends on the design of the rotor vanes and how air flows through it.
As for the brake squeal, other than the grease, did you do a brake bedding procedure after you did the install?
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Now I'm really confused! I did the grease and did somewhat of a break-in procedure. I've heard different opinions on breaking them in though, so I went easy on them for a couple hundred miles and then did some hard stops after that. What do most people recomend for breaking brakes in? By the way, My wife drove the car in the rain the other day and said that the brakes did not want to stop. At the time the slots were swooping forward, so I think I'll switch them back and try over again and see what happens. Thanks to jeremyp111 and neo for your help. Any more info would be great
#9
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Here is a little reading on the rotors. This is specific to the StopTech rotors. You are going to have to inspect your rotors to see how it is built. Maybe you can ask at the place you bought them.
http://www.stoptech.com/faq/data/faq16.html
Breakin:
http://www.stoptech.com/faq/data/faq7.html
Here is the bedding procedure copied from another thread:
http://www.stoptech.com/faq/data/faq16.html
Breakin:
http://www.stoptech.com/faq/data/faq7.html
Here is the bedding procedure copied from another thread:
If you've just installed a big brake kit or even if you've only changed your brake pads and rotors, you should "bed" them in by following the instructions below. Proper bedding of brakes will improve pedal feel, reduce or eliminate brake squeal, and extend the life of your pads and rotors.
When following these instructions, please avoid doing it in the presence of other vehicles. Breaking in your new pads and rotors is often best done very early in the morning, since other drivers will have no idea what you are up to and will respond in a variety of ways ranging from fear to curiosity to aggression. And an officer of the law will probably not understand when you try to explain why you were driving so erratically!
From a speed of about 60mph, gently apply the brakes to slow the car down to about 45mph, then accelerate back up to 60mph and repeat. Do this about four or five times to bring the brakes up to operating temperature. This prevents you from thermally shocking the rotors and pads in the next steps.
Make a series of eight near-stops from 60 to about 10 mph. Do it HARD by pressing on the brakes firmly, just shy of locking the wheels or engaging ABS. At the end of each slowdown, immediately accelerate back to 60mph. DO NOT COME TO A COMPLETE STOP! (Note: With less aggressive street pads and/or stock brake calipers, you may need to do this fewer times. If your pedal gets soft or you feel the brakes going away, then you've done enough. Proceed to the next step.)
During this process, you must not come to a complete stop because you will transfer (imprint) pad material onto the hot rotors, which can lead to vibration, uneven braking, and could even ruin the rotors.
Depending on the pads you are using, the brakes may begin to fade slightly after the 7th or 8th near-stop. This fade will stabilize, but not completely go away until the brakes have fully cooled. A bad smell from the brakes, and even some smoke, is normal.
After the 8th near-stop, accelerate back up to speed and drive around for as long as possible without using the brakes. The brakes will need at least 10 minutes to cool down. Obviously, it's OK to use the brakes to avoid an accident, but try to minimize their use until they have cooled.
After the break-in cycle, there should be a blue tint and a light gray film on the rotor face. The blue tint tells you the rotor has reached break-in temperature and the gray film is pad material starting to transfer onto the rotor face. This is what you are looking for. The best braking occurs when there is an even layer of of pad material deposited across the face of the rotors. This minimizes squealing, increases braking torque, and maximizes pad and rotor life.
After the first break in cycle shown above, the brakes may still not be fully broken in. A second bed-in cycle, AFTER the brakes have cooled down fully from the first cycle, may be necessary before the brakes really start to perform well. If you've just installed a big brake kit, the pedal travel may not feel as firm as you expected. After the second cycle, the pedal will become noticeably firmer.
When following these instructions, please avoid doing it in the presence of other vehicles. Breaking in your new pads and rotors is often best done very early in the morning, since other drivers will have no idea what you are up to and will respond in a variety of ways ranging from fear to curiosity to aggression. And an officer of the law will probably not understand when you try to explain why you were driving so erratically!
From a speed of about 60mph, gently apply the brakes to slow the car down to about 45mph, then accelerate back up to 60mph and repeat. Do this about four or five times to bring the brakes up to operating temperature. This prevents you from thermally shocking the rotors and pads in the next steps.
Make a series of eight near-stops from 60 to about 10 mph. Do it HARD by pressing on the brakes firmly, just shy of locking the wheels or engaging ABS. At the end of each slowdown, immediately accelerate back to 60mph. DO NOT COME TO A COMPLETE STOP! (Note: With less aggressive street pads and/or stock brake calipers, you may need to do this fewer times. If your pedal gets soft or you feel the brakes going away, then you've done enough. Proceed to the next step.)
During this process, you must not come to a complete stop because you will transfer (imprint) pad material onto the hot rotors, which can lead to vibration, uneven braking, and could even ruin the rotors.
Depending on the pads you are using, the brakes may begin to fade slightly after the 7th or 8th near-stop. This fade will stabilize, but not completely go away until the brakes have fully cooled. A bad smell from the brakes, and even some smoke, is normal.
After the 8th near-stop, accelerate back up to speed and drive around for as long as possible without using the brakes. The brakes will need at least 10 minutes to cool down. Obviously, it's OK to use the brakes to avoid an accident, but try to minimize their use until they have cooled.
After the break-in cycle, there should be a blue tint and a light gray film on the rotor face. The blue tint tells you the rotor has reached break-in temperature and the gray film is pad material starting to transfer onto the rotor face. This is what you are looking for. The best braking occurs when there is an even layer of of pad material deposited across the face of the rotors. This minimizes squealing, increases braking torque, and maximizes pad and rotor life.
After the first break in cycle shown above, the brakes may still not be fully broken in. A second bed-in cycle, AFTER the brakes have cooled down fully from the first cycle, may be necessary before the brakes really start to perform well. If you've just installed a big brake kit, the pedal travel may not feel as firm as you expected. After the second cycle, the pedal will become noticeably firmer.
#10
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I have irotors and have them swooping forward- I think it looks better that way. I'll call them after the wkend and see what they recommend. But no probs for me w/ them like that
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