Originally Posted By: d00df00d
Originally Posted By: cheesepuffs
Re-read the article.
Alright.
Quote:
First of all you can see that striped or banding is already appearing after this short driving period which is typical of a brake rotor
where the drill holes do not “Overlap” leaving uneven areas of the brake rotor surface contacted by the brake pads.
Quote:
Second
amateur rotor drilling companies
may not take the time to ensure that their drill holes fall into the vent pockets in the rotor which are between the two faces of the brake rotor.
If these THROUGH DRILLED HOLES are drilled right through into the support vanes in the rotor core this will GREATLY weaken the structural strength of the rotor.
(emphasis added)
Pretty clear they're only talking about poorly made drilled rotors.
...Until this point:
Quote:
Even IF the supplier does manage to take the time to locate the through drilled holes to fall into the vent pockets between the vane supports it has been seen
on many occasions that cracks develop around the through drilled holes as shown here. Eventually the rotor cracks and will very likely suffer a catastrophic failure.
On "many" occasions. Not all, or even most. "Many" -- which just means "more than once".
This is exactly what one would expect from a company that plays at price points where drilled rotors are hard to do well, as EBC does. It says little about the concept in and of itself. Brembo, AP Racing, Akebono, Stoptech, and the makers of high-end performance cars have no problem with drilled iron rotors, and I know you're not seriously arguing that those companies -- which, admit it, EBC can't hold a candle to -- would knowingly offer "unsafe" and "dangerous" products just for a few bling points.
Again, I AGREE that drilled rotors probably aren't the right call for this application. Just trying to keep it real here.
Brembo, AP, etc, and major automakers absolutely do contend with cracking rotors in cross-drilled applications. Porsche has service guidelines on how much cracking is allowed before replacement is needed.
https://rennlist.com/forums/996-forum/654567-rotors-hairline-cracks.html
Do you think many of the aftermarket companies that people are buying these rotors from have similar guidelines? Maybe they do, maybe they don’t. Would most people buying stock sized drilled rotors ever even inspect them periodically anyway? I doubt it. This is not a brand specific issue. Even with chamfered holes to eliminate the highest point of stress, that is still only performed on the outer side of the holes, not the inside of those same holes coming into the vents. So there can be internal cracking occurring earlier than you can’t even see. It’s such a pointless risk for no real benefit. Also even on a Porsche with iron cross drilled brakes, like a Boxster S, the iron brakes are still increased in diameter. What does that tell you? Nothing about stock sized replacement rotors with cross drilling sits well with me at all. And do I believe that legitimate brands that otherwise make excellent products would also sell an inferior product for some bling points? Absolutely they would. Just like you can buy a pair of non-polarized Ray-Bans.