Brake upgrades for the track after reviews
4/1/11, 12:31 PM
#121
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So what can be done with to increase the systems effectiveness?
1. Brake Cooling Ducts, braided stainless steel brake lines and brake fluid that has a high boiling point; bleed your brakes before a track day, at the end of track day and even check the color of the fluid at the caliper during the day between sessions to make sure you didn’t over heat/boil the fluid. - Did this during PDI - Check
2. Dedicated rotors for the track!
This will prevent cross contamination of the rotors, e.i. you use a pad from manufacturer “A” for the street and Manufacturer “B” for the track. Well now you have different pad compounds and your rotors get contaminated. - Pulled the DBA 5000/4000s off my GT500 and put new rings on the 5000s - Will run these and DTC 70/60s on track only and swap back to stock for the street - Check
Your braking system is thrown out of whack and you could experience “ice” mode and that is bad because it decreases your brake systems effectiveness and this could lead to not being able to stop…….
3. Now this is a bit more expensive but look at buying two piece rotors for the front; cons: expensive upfront and expensive when you replace the rotors ( IMO, you don’t need “cross drilled” rotors with today’s pads), pros less rotating mass, less prone to crack. - See #2
4. Drive the car around the paddock for a few minutes to cool the rotors. Don't use your parking brake at the track after a session you will hold the heat in one place and you increase the chance of cracking a rotor. Push or pull the car enough to rotate the rotor about half the distance from the calipers so the heat doesn’t stay in one place.....after it's been sitting for a few minutes. - I do this
5. Install the Front Brake Kit FR500S M-2300-J (complete kit w/4pc brake lines) or a similar sized caliper, sized to work with the stock booster/master cylinder, STOPTECH might even be a better idea but that’s a different subject…….Wife's already griping about the mods to date - On hold
1. Brake Cooling Ducts, braided stainless steel brake lines and brake fluid that has a high boiling point; bleed your brakes before a track day, at the end of track day and even check the color of the fluid at the caliper during the day between sessions to make sure you didn’t over heat/boil the fluid. - Did this during PDI - Check
2. Dedicated rotors for the track!
This will prevent cross contamination of the rotors, e.i. you use a pad from manufacturer “A” for the street and Manufacturer “B” for the track. Well now you have different pad compounds and your rotors get contaminated. - Pulled the DBA 5000/4000s off my GT500 and put new rings on the 5000s - Will run these and DTC 70/60s on track only and swap back to stock for the street - Check
Your braking system is thrown out of whack and you could experience “ice” mode and that is bad because it decreases your brake systems effectiveness and this could lead to not being able to stop…….
3. Now this is a bit more expensive but look at buying two piece rotors for the front; cons: expensive upfront and expensive when you replace the rotors ( IMO, you don’t need “cross drilled” rotors with today’s pads), pros less rotating mass, less prone to crack. - See #2
4. Drive the car around the paddock for a few minutes to cool the rotors. Don't use your parking brake at the track after a session you will hold the heat in one place and you increase the chance of cracking a rotor. Push or pull the car enough to rotate the rotor about half the distance from the calipers so the heat doesn’t stay in one place.....after it's been sitting for a few minutes. - I do this
5. Install the Front Brake Kit FR500S M-2300-J (complete kit w/4pc brake lines) or a similar sized caliper, sized to work with the stock booster/master cylinder, STOPTECH might even be a better idea but that’s a different subject…….Wife's already griping about the mods to date - On hold
Good writeup.
4/1/11, 12:41 PM
#122
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The other advantage (bit greater TORQUE from the increased radius at which the clamping force is applied) does increase the decelerative ability of that brake, but what the guys here are saying is too much of the braking is then taken over by the rears, upsetting the overall brake balance (too much rear brake bias, or even earlier lockup, can lead to some pretty bad oversteer situations).
So run the stock rears and be happy!
I refrained at this point from putting a smiley face here!
Last edited by GT_350; 4/1/11 at 12:42 PM.
4/1/11, 01:47 PM
#123
Every competition Mustang that Ford builds uses the stock rear rotor and caliper.
Food for thought.
Food for thought.
5/17/11, 01:14 PM
#124
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Hey guys, I posted this as a new thread but if you're like me and just frequently check the "Subscribed" ones, thought I'd post here as well to get more response:
This is my right rear rotor:
These are symmetric, L & R, inner and outer surface, after 4 track days (2 weekends) this year, four 20 min sessions each day, speeds to 120mph.
The rears are Roush TrakPak rotors, EBC Bluestuff pads, traction control off whenever on track. Front are StopTech/Saleen 4pots w/ two piece discs
The pattern is the internal vanes of the rotor (didn't realize that at first), and as has been said elsewhere, I'm definitely replacing the rotors (going for plain Centric blanks at this point, $36/rotor through TireRacK), and I'll include the StopTech guy's response below as well, but wanted to get y'all's opinion as there are many on here much more experienced than I am in this area.
Is this too hot a rotor (my vote), or too cold?
This is my right rear rotor:
These are symmetric, L & R, inner and outer surface, after 4 track days (2 weekends) this year, four 20 min sessions each day, speeds to 120mph.
The rears are Roush TrakPak rotors, EBC Bluestuff pads, traction control off whenever on track. Front are StopTech/Saleen 4pots w/ two piece discs
The pattern is the internal vanes of the rotor (didn't realize that at first), and as has been said elsewhere, I'm definitely replacing the rotors (going for plain Centric blanks at this point, $36/rotor through TireRacK), and I'll include the StopTech guy's response below as well, but wanted to get y'all's opinion as there are many on here much more experienced than I am in this area.
Is this too hot a rotor (my vote), or too cold?
Josh-
The rear rotors need to be replaced immediately, not doing so could lead to a catastrophic failure. Somewhere on the rotor will be a minimum thickness number, typically it reads “MIN THK XX.Xmm” Whatever that number, you long ago surpassed it.
A few comments… Do both rears look the same? If not, that one corner may have a slider pin on the caliper hanging up or if ABS or traction control is involved, it may be the track configuration(s) you run is making the system think that corner needs more braking. Most likely both are the same, which would point to a set-up or brake pad issue.
What I sense may be happening is the rear brakes are not getting hot enough for the pads you are running. If track pads run too cold, they can become very abrasive and increase rotor wear. I don’t see classic signs of heat, the shiny metal surface shows that. How often do you go through rear pads? I don’t know much about EBC’s pad characteristics, you might ask their recommendations.
Finally, don’t think of rotor wear in terms of calendar days, it is based on miles and conditions. A hard race weekend can shake loose things that 50,000 street miles might never affect. You need to become aware of the minimum wear dimensions (rotor and pads), and keep a closer eye on those things.
Please let us know if you have any further questions-
Matt Weiss
Quality Assurance Manager
StopTech
The rear rotors need to be replaced immediately, not doing so could lead to a catastrophic failure. Somewhere on the rotor will be a minimum thickness number, typically it reads “MIN THK XX.Xmm” Whatever that number, you long ago surpassed it.
A few comments… Do both rears look the same? If not, that one corner may have a slider pin on the caliper hanging up or if ABS or traction control is involved, it may be the track configuration(s) you run is making the system think that corner needs more braking. Most likely both are the same, which would point to a set-up or brake pad issue.
What I sense may be happening is the rear brakes are not getting hot enough for the pads you are running. If track pads run too cold, they can become very abrasive and increase rotor wear. I don’t see classic signs of heat, the shiny metal surface shows that. How often do you go through rear pads? I don’t know much about EBC’s pad characteristics, you might ask their recommendations.
Finally, don’t think of rotor wear in terms of calendar days, it is based on miles and conditions. A hard race weekend can shake loose things that 50,000 street miles might never affect. You need to become aware of the minimum wear dimensions (rotor and pads), and keep a closer eye on those things.
Please let us know if you have any further questions-
Matt Weiss
Quality Assurance Manager
StopTech
5/17/11, 01:35 PM
#125
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Yeah, the Centric Blanks are the way to go!
FYI (I posted this somewhere else), Raybestos are offering a $40 rebate for the ST-43's and ST-41's; GREAT track only pads! Very rotor friendly and can slow down a heavy GT car as well as the DTC-70/60 and PFC-01's! Can't speak about the PF pads, but they also last longer than the Hawks. With the Rebate, we're talking about $220 for front pads
FYI (I posted this somewhere else), Raybestos are offering a $40 rebate for the ST-43's and ST-41's; GREAT track only pads! Very rotor friendly and can slow down a heavy GT car as well as the DTC-70/60 and PFC-01's! Can't speak about the PF pads, but they also last longer than the Hawks. With the Rebate, we're talking about $220 for front pads
5/17/11, 01:54 PM
#126
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Yeah, the Centric Blanks are the way to go!
FYI (I posted this somewhere else), Raybestos are offering a $40 rebate for the ST-43's and ST-41's; GREAT track only pads! Very rotor friendly and can slow down a heavy GT car as well as the DTC-70/60 and PFC-01's! Can't speak about the PF pads, but they also last longer than the Hawks. With the Rebate, we're talking about $220 for front pads
FYI (I posted this somewhere else), Raybestos are offering a $40 rebate for the ST-43's and ST-41's; GREAT track only pads! Very rotor friendly and can slow down a heavy GT car as well as the DTC-70/60 and PFC-01's! Can't speak about the PF pads, but they also last longer than the Hawks. With the Rebate, we're talking about $220 for front pads
5/17/11, 02:35 PM
#127
Are you making sure to disable TCS before going on-track???
Your pads look OK from a temperature perspective as the backing plates are still intact...but make sure you're not jumping or stomping on the brakes...get on the brakes gently and add pressure as needed.
That rotor will definitely need to be replaced.
Your pads look OK from a temperature perspective as the backing plates are still intact...but make sure you're not jumping or stomping on the brakes...get on the brakes gently and add pressure as needed.
That rotor will definitely need to be replaced.
Hey guys, I posted this as a new thread but if you're like me and just frequently check the "Subscribed" ones, thought I'd post here as well to get more response:
This is my right rear rotor:
These are symmetric, L & R, inner and outer surface, after 4 track days (2 weekends) this year, four 20 min sessions each day, speeds to 120mph.
The rears are Roush TrakPak rotors, EBC Bluestuff pads, traction control off whenever on track. Front are StopTech/Saleen 4pots w/ two piece discs
The pattern is the internal vanes of the rotor (didn't realize that at first), and as has been said elsewhere, I'm definitely replacing the rotors (going for plain Centric blanks at this point, $36/rotor through TireRacK), and I'll include the StopTech guy's response below as well, but wanted to get y'all's opinion as there are many on here much more experienced than I am in this area.
Is this too hot a rotor (my vote), or too cold?
This is my right rear rotor:
These are symmetric, L & R, inner and outer surface, after 4 track days (2 weekends) this year, four 20 min sessions each day, speeds to 120mph.
The rears are Roush TrakPak rotors, EBC Bluestuff pads, traction control off whenever on track. Front are StopTech/Saleen 4pots w/ two piece discs
The pattern is the internal vanes of the rotor (didn't realize that at first), and as has been said elsewhere, I'm definitely replacing the rotors (going for plain Centric blanks at this point, $36/rotor through TireRacK), and I'll include the StopTech guy's response below as well, but wanted to get y'all's opinion as there are many on here much more experienced than I am in this area.
Is this too hot a rotor (my vote), or too cold?
Josh-
The rear rotors need to be replaced immediately, not doing so could lead to a catastrophic failure. Somewhere on the rotor will be a minimum thickness number, typically it reads “MIN THK XX.Xmm” Whatever that number, you long ago surpassed it.
A few comments… Do both rears look the same? If not, that one corner may have a slider pin on the caliper hanging up or if ABS or traction control is involved, it may be the track configuration(s) you run is making the system think that corner needs more braking. Most likely both are the same, which would point to a set-up or brake pad issue.
What I sense may be happening is the rear brakes are not getting hot enough for the pads you are running. If track pads run too cold, they can become very abrasive and increase rotor wear. I don’t see classic signs of heat, the shiny metal surface shows that. How often do you go through rear pads? I don’t know much about EBC’s pad characteristics, you might ask their recommendations.
Finally, don’t think of rotor wear in terms of calendar days, it is based on miles and conditions. A hard race weekend can shake loose things that 50,000 street miles might never affect. You need to become aware of the minimum wear dimensions (rotor and pads), and keep a closer eye on those things.
Please let us know if you have any further questions-
Matt Weiss
Quality Assurance Manager
StopTech
The rear rotors need to be replaced immediately, not doing so could lead to a catastrophic failure. Somewhere on the rotor will be a minimum thickness number, typically it reads “MIN THK XX.Xmm” Whatever that number, you long ago surpassed it.
A few comments… Do both rears look the same? If not, that one corner may have a slider pin on the caliper hanging up or if ABS or traction control is involved, it may be the track configuration(s) you run is making the system think that corner needs more braking. Most likely both are the same, which would point to a set-up or brake pad issue.
What I sense may be happening is the rear brakes are not getting hot enough for the pads you are running. If track pads run too cold, they can become very abrasive and increase rotor wear. I don’t see classic signs of heat, the shiny metal surface shows that. How often do you go through rear pads? I don’t know much about EBC’s pad characteristics, you might ask their recommendations.
Finally, don’t think of rotor wear in terms of calendar days, it is based on miles and conditions. A hard race weekend can shake loose things that 50,000 street miles might never affect. You need to become aware of the minimum wear dimensions (rotor and pads), and keep a closer eye on those things.
Please let us know if you have any further questions-
Matt Weiss
Quality Assurance Manager
StopTech
5/17/11, 02:38 PM
#128
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5/17/11, 02:39 PM
#129
Related to my advice:
5/17/11, 02:46 PM
#130
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Originally Posted by 06GT
Related to my advice:
<a href="http://www.youtube.com/watch?v=UJPS5_kj4zw">YouTube Link</a>
<a href="http://www.youtube.com/watch?v=2OCgmUDYUwQ">YouTube Link</a>
<a href="http://www.youtube.com/watch?v=UJPS5_kj4zw">YouTube Link</a>
<a href="http://www.youtube.com/watch?v=2OCgmUDYUwQ">YouTube Link</a>
5/17/11, 03:21 PM
#131
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Cool vids. Yea I've never had an issue kicking off ABS with the Hawk DTCs and you can stop on a dime. The only thing is they thrash the front rotors but man do they stop the car. The only time I've ever kicked off the ABS was during one session last time out with the Boss, I turned off the car in the staging lane to talk to the track manager for a minute and when I restarted it, I didn't hold the AdvanceTrac off long enough 
Man I hate that thing. ABS was going nuts and I had to pull into the hot pits and turn it off again. The GT500 is just a simple push of the TCS off button and it's all off. Holding for a full 5 seconds with the brake applied is a PITA. Plus I don't like it on track days if you are doing it with still somewhat hot brakes for fear of hot spotting the rotors.
Man I hate that thing. ABS was going nuts and I had to pull into the hot pits and turn it off again. The GT500 is just a simple push of the TCS off button and it's all off. Holding for a full 5 seconds with the brake applied is a PITA. Plus I don't like it on track days if you are doing it with still somewhat hot brakes for fear of hot spotting the rotors.
5/17/11, 03:26 PM
#132
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Yep, disable the TCS for each session, nice simple one button-push 
What you're seeing in the picture is my new, replaced pads, done over the weekend at the track. The prior ones didn't look too bad, like a bunch of heat cycles but okay otherwise. One side did have a mirror image uneven thickness across their length (triangle on one pad, opposite triangle on the other pad), and the EBC backing shim pieces always fall off, but the pad material was still tight to the backing plate.
Thanks for the input on them from everybody. I'm gathering alot of this might be keeping the rotors on for too long, too many sessions, so going to cheap rotors to replace more frequently.
What you're seeing in the picture is my new, replaced pads, done over the weekend at the track. The prior ones didn't look too bad, like a bunch of heat cycles but okay otherwise. One side did have a mirror image uneven thickness across their length (triangle on one pad, opposite triangle on the other pad), and the EBC backing shim pieces always fall off, but the pad material was still tight to the backing plate.
Thanks for the input on them from everybody. I'm gathering alot of this might be keeping the rotors on for too long, too many sessions, so going to cheap rotors to replace more frequently.
5/17/11, 04:20 PM
#133
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Here's a good explanation from one of our local CMC (Crapmaro Mustang Challenge) racers, seems the most plausible yet:
I've only seen that pattern on front rotors that were already cut thin and were probably at or past minimum thickness due to excessive wear. The likely concern is a weakness in the structure and imminent rotor failure. That's probably why the suggestion was made to replace them immediately. If the rotors aren't down to minimum thickness and don't appear to be physically damaged from warpage or cracking, I wouldn't get rid of them yet. Instead, I'd try to clean them up and get rid of all pad material deposition areas with some garnet paper and test some other things out.
There's probably a combination of things at work here, but what appears is happening is there is an alternating pad material deposition/scrubbing (or non-deposition) that is happening across the face of the rotors that is either due to 1) the rotors undergoing a deformation due to a differential in heating through the rotor based on the vane pattern or a lack of a rigid enough rotor structure to prevent deformation, or 2) there is a differential deposition of pad material across the face of the rotor due to localized hot spots based on the cooling vane pattern.
The location of the deposition either between the vanes or along the vanes may help you figure out what is going on.
If the rotors are too thin or are cheaply made and do not have enough mass through the internal vane structure, they could deform and cause that pattern. That may also imply heat is being put too quickly into only one portion of the rotor, or heat is being removed too quickly in another. With such deformation due to heat, you should also see signs of cracking. If this is the case, try different rotors.
If you are not seeing signs of cracking, the rotors may not be undergoing a deformation, but may still be getting localized pad material deposition across the rotor face based on hot/cool spots related to the rotor vane pattern. This could depend on the heat range of your pad material and the range of temperatures your rotors are experiencing. It may also be due to an overly/underly aggressive pad bedding procedure that originally created the hotter/cooler spots that led to the differential pad material deposition.
One last thought. Did you remove the old pad material that was embedded in the rotor surfaces before you bedded the new pads into the rotors? Different pad materials can interact unfavorably with each other. I could see this happening in localized areas as the rotors heated up during the bedding-in procedure or during hard use. If this could be the case, if you clean the rotors and pad faces up with some garnet paper and try rebedding the pads, that may be the cheap and easy way to overcome this issue. (I'm all about cheap and easy solutions.) If this does not solve the problem and all of the other mechanical aspects of the brakes are good, I would try a combination of different pads and different rotors before adding any cooling ducts.
I've only seen that pattern on front rotors that were already cut thin and were probably at or past minimum thickness due to excessive wear. The likely concern is a weakness in the structure and imminent rotor failure. That's probably why the suggestion was made to replace them immediately. If the rotors aren't down to minimum thickness and don't appear to be physically damaged from warpage or cracking, I wouldn't get rid of them yet. Instead, I'd try to clean them up and get rid of all pad material deposition areas with some garnet paper and test some other things out.
There's probably a combination of things at work here, but what appears is happening is there is an alternating pad material deposition/scrubbing (or non-deposition) that is happening across the face of the rotors that is either due to 1) the rotors undergoing a deformation due to a differential in heating through the rotor based on the vane pattern or a lack of a rigid enough rotor structure to prevent deformation, or 2) there is a differential deposition of pad material across the face of the rotor due to localized hot spots based on the cooling vane pattern.
The location of the deposition either between the vanes or along the vanes may help you figure out what is going on.
If the rotors are too thin or are cheaply made and do not have enough mass through the internal vane structure, they could deform and cause that pattern. That may also imply heat is being put too quickly into only one portion of the rotor, or heat is being removed too quickly in another. With such deformation due to heat, you should also see signs of cracking. If this is the case, try different rotors.
If you are not seeing signs of cracking, the rotors may not be undergoing a deformation, but may still be getting localized pad material deposition across the rotor face based on hot/cool spots related to the rotor vane pattern. This could depend on the heat range of your pad material and the range of temperatures your rotors are experiencing. It may also be due to an overly/underly aggressive pad bedding procedure that originally created the hotter/cooler spots that led to the differential pad material deposition.
One last thought. Did you remove the old pad material that was embedded in the rotor surfaces before you bedded the new pads into the rotors? Different pad materials can interact unfavorably with each other. I could see this happening in localized areas as the rotors heated up during the bedding-in procedure or during hard use. If this could be the case, if you clean the rotors and pad faces up with some garnet paper and try rebedding the pads, that may be the cheap and easy way to overcome this issue. (I'm all about cheap and easy solutions.) If this does not solve the problem and all of the other mechanical aspects of the brakes are good, I would try a combination of different pads and different rotors before adding any cooling ducts.
5/17/11, 08:08 PM
#134
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Here's a good explanation from one of our local CMC (Crapmaro Mustang Challenge) racers, seems the most plausible yet:
I've only seen that pattern on front rotors that were already cut thin and were probably at or past minimum thickness due to excessive wear. The likely concern is a weakness in the structure and imminent rotor failure. That's probably why the suggestion was made to replace them immediately. If the rotors aren't down to minimum thickness and don't appear to be physically damaged from warpage or cracking, I wouldn't get rid of them yet. Instead, I'd try to clean them up and get rid of all pad material deposition areas with some garnet paper and test some other things out.
There's probably a combination of things at work here, but what appears is happening is there is an alternating pad material deposition/scrubbing (or non-deposition) that is happening across the face of the rotors that is either due to 1) the rotors undergoing a deformation due to a differential in heating through the rotor based on the vane pattern or a lack of a rigid enough rotor structure to prevent deformation, or 2) there is a differential deposition of pad material across the face of the rotor due to localized hot spots based on the cooling vane pattern.
The location of the deposition either between the vanes or along the vanes may help you figure out what is going on.
If the rotors are too thin or are cheaply made and do not have enough mass through the internal vane structure, they could deform and cause that pattern. That may also imply heat is being put too quickly into only one portion of the rotor, or heat is being removed too quickly in another. With such deformation due to heat, you should also see signs of cracking. If this is the case, try different rotors.
If you are not seeing signs of cracking, the rotors may not be undergoing a deformation, but may still be getting localized pad material deposition across the rotor face based on hot/cool spots related to the rotor vane pattern. This could depend on the heat range of your pad material and the range of temperatures your rotors are experiencing. It may also be due to an overly/underly aggressive pad bedding procedure that originally created the hotter/cooler spots that led to the differential pad material deposition.
One last thought. Did you remove the old pad material that was embedded in the rotor surfaces before you bedded the new pads into the rotors? Different pad materials can interact unfavorably with each other. I could see this happening in localized areas as the rotors heated up during the bedding-in procedure or during hard use. If this could be the case, if you clean the rotors and pad faces up with some garnet paper and try rebedding the pads, that may be the cheap and easy way to overcome this issue. (I'm all about cheap and easy solutions.) If this does not solve the problem and all of the other mechanical aspects of the brakes are good, I would try a combination of different pads and different rotors before adding any cooling ducts.
I've only seen that pattern on front rotors that were already cut thin and were probably at or past minimum thickness due to excessive wear. The likely concern is a weakness in the structure and imminent rotor failure. That's probably why the suggestion was made to replace them immediately. If the rotors aren't down to minimum thickness and don't appear to be physically damaged from warpage or cracking, I wouldn't get rid of them yet. Instead, I'd try to clean them up and get rid of all pad material deposition areas with some garnet paper and test some other things out.
There's probably a combination of things at work here, but what appears is happening is there is an alternating pad material deposition/scrubbing (or non-deposition) that is happening across the face of the rotors that is either due to 1) the rotors undergoing a deformation due to a differential in heating through the rotor based on the vane pattern or a lack of a rigid enough rotor structure to prevent deformation, or 2) there is a differential deposition of pad material across the face of the rotor due to localized hot spots based on the cooling vane pattern.
The location of the deposition either between the vanes or along the vanes may help you figure out what is going on.
If the rotors are too thin or are cheaply made and do not have enough mass through the internal vane structure, they could deform and cause that pattern. That may also imply heat is being put too quickly into only one portion of the rotor, or heat is being removed too quickly in another. With such deformation due to heat, you should also see signs of cracking. If this is the case, try different rotors.
If you are not seeing signs of cracking, the rotors may not be undergoing a deformation, but may still be getting localized pad material deposition across the rotor face based on hot/cool spots related to the rotor vane pattern. This could depend on the heat range of your pad material and the range of temperatures your rotors are experiencing. It may also be due to an overly/underly aggressive pad bedding procedure that originally created the hotter/cooler spots that led to the differential pad material deposition.
One last thought. Did you remove the old pad material that was embedded in the rotor surfaces before you bedded the new pads into the rotors? Different pad materials can interact unfavorably with each other. I could see this happening in localized areas as the rotors heated up during the bedding-in procedure or during hard use. If this could be the case, if you clean the rotors and pad faces up with some garnet paper and try rebedding the pads, that may be the cheap and easy way to overcome this issue. (I'm all about cheap and easy solutions.) If this does not solve the problem and all of the other mechanical aspects of the brakes are good, I would try a combination of different pads and different rotors before adding any cooling ducts.
5/17/11, 08:47 PM
#135
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This is more or less what I was thinking. The rotors don't look like they are too thin. Typically with slotted rotors the slots are cut to the min thickness of the rotor, so when the slots start to disappear it's time to replace the rotors. From the picture it looks like you glazed the rotors except for were the cooling fins are. I'm not familiar with Bluestuff pads but glazing is caused by over heating the pads. I would replace the rotors and use a pad capable of higher temps.
"The Vac-U-SlotTM also serves as a visual wear indicator. The slot is machined to the rotors minimum thickness where it crosses the outside edge. If you cannot see the slot along the outside edge, the rotor has worn down to the discard depth"
http://www.centricparts.com/index.ph...d=25&Itemid=80
So I think they're too thin, the slot doesn't seem to go to the edge (still need to measure with a caliper, though).
5/18/11, 08:55 AM
#136
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Help for the novice Please
I Have tracked my boss for the first time (for Both of us). I bed the (stock) brake pads according to the manual for tracking. I had 5 20 min track sessions. I had the rear diff serviced (as instructed). I had Willwoood 600 brake fluid added after the bedding and track session. I would normally do this myself but was short on time this week, and I am a novice and don't want to take any chances. I am off to my second track session so I pulled the front wheel to inspect the pads. They look like they have plenty of material left.
Questions:
I have changed pads on my SN95, but never Brembos. I am assuming the pads come out the wide slot in the back of the caliper, no need to remove the caliper? Correct? Similar to this Video?( Except the Practice of retracting the piston with a Screw driver, OUCH!)
http://www.youtube.com/watch?v=LZLX3jkgsJw
Also, The caliper looks to have a bleed nipple on the inside and outside of the caliper. Is the correct process to bleed both sides?
Also, to remove the caliper, it looks like the brake line has to be unbolted to give a range of travel? is that correct?
Questions:
I have changed pads on my SN95, but never Brembos. I am assuming the pads come out the wide slot in the back of the caliper, no need to remove the caliper? Correct? Similar to this Video?( Except the Practice of retracting the piston with a Screw driver, OUCH!)
http://www.youtube.com/watch?v=LZLX3jkgsJw
Also, The caliper looks to have a bleed nipple on the inside and outside of the caliper. Is the correct process to bleed both sides?
Also, to remove the caliper, it looks like the brake line has to be unbolted to give a range of travel? is that correct?
Last edited by Bossdog; 5/18/11 at 08:59 AM.
5/18/11, 09:16 AM
#138
Shelby GT350 Member
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Location: Sioux Falls, SD
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Questions:
I have changed pads on my SN95, but never Brembos. I am assuming the pads come out the wide slot in the back of the caliper, no need to remove the caliper? Correct? Similar to this Video?( Except the Practice of retracting the piston with a Screw driver, OUCH!)
http://www.youtube.com/watch?v=LZLX3jkgsJw
Also, The caliper looks to have a bleed nipple on the inside and outside of the caliper. Is the correct process to bleed both sides?
Also, to remove the caliper, it looks like the brake line has to be unbolted to give a range of travel? is that correct?
I have changed pads on my SN95, but never Brembos. I am assuming the pads come out the wide slot in the back of the caliper, no need to remove the caliper? Correct? Similar to this Video?( Except the Practice of retracting the piston with a Screw driver, OUCH!)
http://www.youtube.com/watch?v=LZLX3jkgsJw
Also, The caliper looks to have a bleed nipple on the inside and outside of the caliper. Is the correct process to bleed both sides?
Also, to remove the caliper, it looks like the brake line has to be unbolted to give a range of travel? is that correct?
5/18/11, 09:39 AM
#139
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Other points:
The brake line is usually ziptied or otherwise attached to the spindle along the length of the line, you should be able to slide this along the line to give enough length to remove the caliper, if you need to (usually only if swapping out rotors).
Compressing the pistons is easiest done with that side's bleeder screw open and hooked up to a drain bottle, just watch the level in the master cylinder so it doesn't get too low. You might also look into a Speedbleeder, google search and you should find the right size for the Brembos -- one way valved to prevent drawing air back into the caliper.
Rocking the disc back and forth initially against the compressed calipers should be enough to loosen the entire assembly, then if you can slip out one pad, turn 90 degrees, with pad material against the disc, wedge the pad back and forth against piston/disc to compress the piston back into the caliper, again with that side's bleeder screw open.
The brake line is usually ziptied or otherwise attached to the spindle along the length of the line, you should be able to slide this along the line to give enough length to remove the caliper, if you need to (usually only if swapping out rotors).
Compressing the pistons is easiest done with that side's bleeder screw open and hooked up to a drain bottle, just watch the level in the master cylinder so it doesn't get too low. You might also look into a Speedbleeder, google search and you should find the right size for the Brembos -- one way valved to prevent drawing air back into the caliper.
Rocking the disc back and forth initially against the compressed calipers should be enough to loosen the entire assembly, then if you can slip out one pad, turn 90 degrees, with pad material against the disc, wedge the pad back and forth against piston/disc to compress the piston back into the caliper, again with that side's bleeder screw open.
5/18/11, 09:39 AM
#140
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Thanks for the help Guys. Very much appreciated. After this weekends track session I will take off the rotors and pads for learning purposes. I plan to get a track set of rotors and pads as suggested and leave the back stock.
Last edited by Bossdog; 5/18/11 at 09:50 AM.