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Have you ever heard that cross drilled brake rotors crack? Here's the story...


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From what I've heard the DBA rotors were drilled after they were fabricated? While the Porsche and other high-end rotors had the holes cast from factory?

Drilling post-fabrication gives less structural integrity doesn't it?

I could be wrong though..

If they are cast from factory, there is no reason why they would crack from the holes. They would have as much chance cracking from the holes as cracking from the outside perimeter of the disc.

Drilling certainly gives less structural integrity, it creates stress concentrations.

how do they explain that?? if theyre so bad for track work why do all hardcore racecars have em?

which hardcore race cars have cross drilled rotors?

Maybe the porsche carbon rotors but I assume they have different properties.

But what is wrong with good old slotted rotors, or even better nice, quiet, flat rotors for street use?

In airline use, there is a method of riveting where a big-ass pincher squeezes the metal so hard it makes a hole. Because the material isnt lost but is puched to the side, it reinforces the edges of the hole and makes it as strong as if there wasnt a hole there. There were numerous Airliners that failed due to metal fatigue like this. One where the skin of the plane split at passenger window and ripped open the top half of the cabin, and another one that opened up the luggage compartment because of cracking of fatigue on the rivets.

In airline use, there is a method of riveting where a big-ass pincher squeezes the metal so hard it makes a hole. Because the material isnt lost but is puched to the side, it reinforces the edges of the hole and makes it as strong as if there wasnt a hole there. There were numerous Airliners that failed due to metal fatigue like this. One where the skin of the plane split at passenger window and ripped open the top half of the cabin, and another one that opened up the luggage compartment because of cracking of fatigue on the rivets.

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