Brake Rotors
#1
Brake Rotors
Guys I need to replace the rotors on my 996-4S, the intended use for the car is street driving and some DE days. I have been reading many threads here in reference to brakes in general, and it seems there are many opinions in reference to brake pads and rotors.
While not 100% on top of it, I can see and understand the need for a different pad material depending on its intended use, track, DE, street, etc.
What I am a bit confused on, is the differences on rotors, I know drilled vs slotted, and ceramic vs steel, but even between the same type there is a huge difference on price for what, to me, seem to be the same consumable piece of steel. Am I missing something? I mean I figure after a few track days any brand rotor will crack and would need to be replaced, so why spend additional money on this part?
BTW, I am considering Cool Carbon pads and WBR Rotors, these rotors are $58 each and are drilled. What do you guys think.
https://shop.advanceautoparts.com/p/...921%7CL2*16462
While not 100% on top of it, I can see and understand the need for a different pad material depending on its intended use, track, DE, street, etc.
What I am a bit confused on, is the differences on rotors, I know drilled vs slotted, and ceramic vs steel, but even between the same type there is a huge difference on price for what, to me, seem to be the same consumable piece of steel. Am I missing something? I mean I figure after a few track days any brand rotor will crack and would need to be replaced, so why spend additional money on this part?
BTW, I am considering Cool Carbon pads and WBR Rotors, these rotors are $58 each and are drilled. What do you guys think.
https://shop.advanceautoparts.com/p/...921%7CL2*16462
#3
It's hard to go wrong with OEM Porsche or Zimmerman E coat rotors (which are the same thing but less expensive at pelican parts) The factory stuff is pretty awesome and swapping out the pads for a DE event is really easy.
#4
Guys I need to replace the rotors on my 996-4S, the intended use for the car is street driving and some DE days. I have been reading many threads here in reference to brakes in general, and it seems there are many opinions in reference to brake pads and rotors.
While not 100% on top of it, I can see and understand the need for a different pad material depending on its intended use, track, DE, street, etc.
What I am a bit confused on, is the differences on rotors, I know drilled vs slotted, and ceramic vs steel, but even between the same type there is a huge difference on price for what, to me, seem to be the same consumable piece of steel. Am I missing something? I mean I figure after a few track days any brand rotor will crack and would need to be replaced, so why spend additional money on this part?
BTW, I am considering Cool Carbon pads and WBR Rotors, these rotors are $58 each and are drilled. What do you guys think.
https://shop.advanceautoparts.com/p/...921%7CL2*16462
While not 100% on top of it, I can see and understand the need for a different pad material depending on its intended use, track, DE, street, etc.
What I am a bit confused on, is the differences on rotors, I know drilled vs slotted, and ceramic vs steel, but even between the same type there is a huge difference on price for what, to me, seem to be the same consumable piece of steel. Am I missing something? I mean I figure after a few track days any brand rotor will crack and would need to be replaced, so why spend additional money on this part?
BTW, I am considering Cool Carbon pads and WBR Rotors, these rotors are $58 each and are drilled. What do you guys think.
https://shop.advanceautoparts.com/p/...921%7CL2*16462
#5
Nordschleife Master
Joined: Nov 2008
Posts: 5,815
Likes: 55
From: Mooresville, IN (Life Long Cheesehead)
I have used partsgeek for my brake rotors. Not knowing what year your car is I just plugged in a 2003 4S. https://www.partsgeek.com/catalog/20...ake_rotor.html
Ate and Sebro are good rotors. I have slotted or cross drilled whatever your flavor. I've bought uncoated rotors and get a can of zinc rich primer and spray the rotor hats inside and out. As for pads I have used Pagids, PFC and Carbotech. The more aggressive the pad the motor rotor usage you'll see. For street pads I some inexpensive pads that I change out. Also it seems partsgeek's inventory changes and you can find some very good buys every once in a while.
If you are just starting out with DE's just go with your street pads and learn from there.
Ate and Sebro are good rotors. I have slotted or cross drilled whatever your flavor. I've bought uncoated rotors and get a can of zinc rich primer and spray the rotor hats inside and out. As for pads I have used Pagids, PFC and Carbotech. The more aggressive the pad the motor rotor usage you'll see. For street pads I some inexpensive pads that I change out. Also it seems partsgeek's inventory changes and you can find some very good buys every once in a while.
If you are just starting out with DE's just go with your street pads and learn from there.
#6
I suggest avoiding the crossdrilled, which is a misnomer anyway, they are not drilled, they are cast with the holes. Drilling all those holes would make them very expensive. The holes are known to cause cracking. While not on a 911, I have personally seen rotors cracked, and the cracks always start at a hole. The slotted rotors increase elimination of the gases that build up at extreme temps between pad and rotor without sacrificing structural integrity of through holes. I replaced mine when the original warped with slotted ones from Pelican, and have done several DEs with them.
The most recent DE, my car actually did back-to-back sessions with me driving one class and my Daughter driving another class. With temps in the mid 90s, we finally boiled the brake fluid on the second day, but otherwise they held up nicely. I use Castrol GT brake fluid because its the highest boiling point of any reasonably priced dot3/dot4 fluid. Yes, you can get higher BP, but the price goes outa sight for those.
The suggestion to change out pads for DE versus street usage is a very good one, but I would suggest marking the pads so you put the same pad back in the same location it came out of. I believe this will reduce hotspots caused by variations in facing, IOW a pad may be touching the rotor in only one area versus more distributed across the face of the pad/rotor once its seated.
Last, I suggest looking at the GT2/GT3 cooling ducts which can be added to the non-GTx cars very inexpensively. Here is the more expensive version: https://www.suncoastparts.com/produc...634111890.html and here is a cheaper version https://www.suncoastparts.com/product/PKGT3FRS.html both are EOM Porsche parts.
The most recent DE, my car actually did back-to-back sessions with me driving one class and my Daughter driving another class. With temps in the mid 90s, we finally boiled the brake fluid on the second day, but otherwise they held up nicely. I use Castrol GT brake fluid because its the highest boiling point of any reasonably priced dot3/dot4 fluid. Yes, you can get higher BP, but the price goes outa sight for those.
The suggestion to change out pads for DE versus street usage is a very good one, but I would suggest marking the pads so you put the same pad back in the same location it came out of. I believe this will reduce hotspots caused by variations in facing, IOW a pad may be touching the rotor in only one area versus more distributed across the face of the pad/rotor once its seated.
Last, I suggest looking at the GT2/GT3 cooling ducts which can be added to the non-GTx cars very inexpensively. Here is the more expensive version: https://www.suncoastparts.com/produc...634111890.html and here is a cheaper version https://www.suncoastparts.com/product/PKGT3FRS.html both are EOM Porsche parts.
#7
I'd like to hear more proof about holes causing cracking. Would Porsche and others continue to use rotors with holes if they were weaker? I get it that a knock-off cheap rotor with holes is not the way to go, but OEM? And Porsche OEM? A company that prides itself on selling race-ready street cars?
Are the upgrades/premium brakes on high end performance cars more often cast with holes or solid?
I'm really just asking, not telling anyone. I'd like to see hard evidence here. Scientific. And as for those cracked rotors that started at the holes, maybe those rotors were well worn and being operated at or beyond their minimum thickness standards?
Has anyone tested these things? (I would assume the manufacturers have.)
Are the upgrades/premium brakes on high end performance cars more often cast with holes or solid?
I'm really just asking, not telling anyone. I'd like to see hard evidence here. Scientific. And as for those cracked rotors that started at the holes, maybe those rotors were well worn and being operated at or beyond their minimum thickness standards?
Has anyone tested these things? (I would assume the manufacturers have.)
Trending Topics
#8
I'd like to hear more proof about holes causing cracking. Would Porsche and others continue to use rotors with holes if they were weaker? I get it that a knock-off cheap rotor with holes is not the way to go, but OEM? And Porsche OEM? A company that prides itself on selling race-ready street cars?
Are the upgrades/premium brakes on high end performance cars more often cast with holes or solid?
I'm really just asking, not telling anyone. I'd like to see hard evidence here. Scientific. And as for those cracked rotors that started at the holes, maybe those rotors were well worn and being operated at or beyond their minimum thickness standards?
Has anyone tested these things? (I would assume the manufacturers have.)
Are the upgrades/premium brakes on high end performance cars more often cast with holes or solid?
I'm really just asking, not telling anyone. I'd like to see hard evidence here. Scientific. And as for those cracked rotors that started at the holes, maybe those rotors were well worn and being operated at or beyond their minimum thickness standards?
Has anyone tested these things? (I would assume the manufacturers have.)
#10
I replaced porsche rotors on my GT3 with 16000 miles ( I tracked it couple of times and previous owners seemed to have) and cracks had started from the holes and started growing. As stated, it is a well-known issue and so long as they are replaced before cracks connect holes or reach the outer edge of the rotor, risk is minimal. I prefer slotted rotors, which I use on my e36 M3 for track driving, but for 996 C4S, Sebro seems to be the only one making one at reasonable price.
#11
I'd like to hear more proof about holes causing cracking. Would Porsche and others continue to use rotors with holes if they were weaker? I get it that a knock-off cheap rotor with holes is not the way to go, but OEM? And Porsche OEM? A company that prides itself on selling race-ready street cars?
Are the upgrades/premium brakes on high end performance cars more often cast with holes or solid?
I'm really just asking, not telling anyone. I'd like to see hard evidence here. Scientific. And as for those cracked rotors that started at the holes, maybe those rotors were well worn and being operated at or beyond their minimum thickness standards?
Has anyone tested these things? (I would assume the manufacturers have.)
Are the upgrades/premium brakes on high end performance cars more often cast with holes or solid?
I'm really just asking, not telling anyone. I'd like to see hard evidence here. Scientific. And as for those cracked rotors that started at the holes, maybe those rotors were well worn and being operated at or beyond their minimum thickness standards?
Has anyone tested these things? (I would assume the manufacturers have.)
Porsche could go to a slotted rotor.....but then they would lose out on all the money they make replacing the OEM drilled/cast rotors.
__________________
Clark
ApexPerformance.net
Premier Racing Outfitters
Toll free: 866-505-2739
Direct: 843-299-0997
EM: chamerly@apexperformance.net
www.apexperformance.net
Save 10% on your next order over $75 on most items- enter Promocode Rennlist-10 on your next order or mention Rennlist during your phone order.
PCA Club Racing - National Sponsor
Clark
ApexPerformance.net
Premier Racing Outfitters
Toll free: 866-505-2739
Direct: 843-299-0997
EM: chamerly@apexperformance.net
www.apexperformance.net
Save 10% on your next order over $75 on most items- enter Promocode Rennlist-10 on your next order or mention Rennlist during your phone order.
PCA Club Racing - National Sponsor
#12
Are those even steel rotors? I probably should have been more specific, but Im only talking about low-end (like I would buy) machined cast steel rotors, not top shelf carbon fiber impregnated blah blah blah $10,000 a set rotors. That car looks to be a GTx or cup car, and the mechanic is torquing the 400ftlb center lug. I probably cannot even afford that torque wrench.
#14
Are those even steel rotors? I probably should have been more specific, but Im only talking about low-end (like I would buy) machined cast steel rotors, not top shelf carbon fiber impregnated blah blah blah $10,000 a set rotors. That car looks to be a GTx or cup car, and the mechanic is torquing the 400ftlb center lug. I probably cannot even afford that torque wrench.
#15
When I was 16, back in 1979/1980, I was at the local British car dealership (they may have had a Porsche and Mercedes dealership too) on route 17 in NJ getting parts for my MGB. I remember there was a huge disk brake rotor on the counter that was cross drilled. The steel was all the colors of the rainbow and all if the holes were connected with little cracks. I remember thinking how beautiful it was, in a way engineers can appreciate. I asked them what car it came off of and they said "a Porsche 917".