SPEC 996 "New PCA Class for 2011"
#243
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This happened last year. I'm not sure if it was OEM as it was already on the car when I purchases it. I don't think there's an OEM cross drilled AND slotted rotor, but I could be wrong.
The crack propagates from one of the holes to the outer edge. This is why I attribute the failure to the cross drilling. I may be wrong but cracks eminating from these holes is very common-at least in my limited experience.
The crack propagates from one of the holes to the outer edge. This is why I attribute the failure to the cross drilling. I may be wrong but cracks eminating from these holes is very common-at least in my limited experience.
#245
Three Wheelin'
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This happened last year. I'm not sure if it was OEM as it was already on the car when I purchases it. I don't think there's an OEM cross drilled AND slotted rotor, but I could be wrong.
The crack propagates from one of the holes to the outer edge. This is why I attribute the failure to the cross drilling. I may be wrong but cracks eminating from these holes is very common-at least in my limited experience.
The crack propagates from one of the holes to the outer edge. This is why I attribute the failure to the cross drilling. I may be wrong but cracks eminating from these holes is very common-at least in my limited experience.
It appear the primary crack started mid way between the edge and hole (circled in red) from Heat saturation. Again, just my opinion.
#246
The Penguin King
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#247
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I use to track a 996TT, much faster and MUCH heavier. Had to replace front rotors often due to cracking. Eventually upgraded the brakes to 6 piston and 2 pc floating. Most of the cracks, by far, started at the drilled holes and propagated outward. Most people advised that the rotors needed to be replaced whenever a crack from on hole met another or the edge of the disc. Never had a failure like this on the turbo (thank God), but I feel the causes in both cases are attributable to the holes, at least in part. The failure pictured just confirmed my sentiment that crossed-drilled rotors suck for tracking. Again just my opinion.
#248
Three Wheelin'
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I could see in the photo that the area I indicated was deformed. so after years of analyzing failures from worse imagery... I can say that it really was not the holes fault.
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#250
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Look, I don't want or need to get into a pissing match about this rotor/crack. We all have our preferences based on our experiences. Good luck to you with your's and I wish you the best. Based on my experiences I don't see any disadvantage to avoiding crossed drilled rotors for track use when possible.
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#251
Nordschleife Master
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Since I built my 996 in July 09', I've probably put in excess of 70 hours on it running both POC and NASA's full schedule of 17-18 races each per year. To date I've replaced one, that's correct, 1 front cross drilled OEM rotor. I run Pagid RS29's up front, RS 14's rear. Yea I've got some cracks between the holes, but none to the outside edge. You guys need to quit braking so much
.....
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#252
RL Community Team
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It's nice to be light, with lots of rubber! ![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
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Since I built my 996 in July 09', I've probably put in excess of 70 hours on it running both POC and NASA's full schedule of 17-18 races each per year. To date I've replaced one, that's correct, 1 front cross drilled OEM rotor. I run Pagid RS29's up front, RS 14's rear. Yea I've got some cracks between the holes, but none to the outside edge. You guys need to quit braking so much
.....
![Embarrassment](https://rennlist.com/forums/images/smilies/redface.gif)
#253