[1and1]

Originally Posted by Aceway

I think you installed them on the wrong sides

Nope- they're labeled for the side, and the vanes are directional making it really easy to see the orientation.

And, fwiw, they match the installed pics from the site too (which I looked up to double check cause I thought they looked backwards too)

Besides, it makes no difference which direction the holes & slots lean, it's all about the directional vanes.
https://www.zeckhausen.com/catalog/i...Path=6446_6515

It is not possible to tell if a drilled rotor is installed properly, simply by observing the drill pattern. Different manufacturers use different patterns with spiral "arms" that appear to lean in either direction, regardless of the internal cooling fin orientation. For example, StopTech AeroRotors, used on their big brake kits, have a drill pattern that appears to lean to the front of the car. Porsche OEM rotors have a drill pattern that appears to lean to the back of the car. In both cases, the internal cooling fins are properly oriented, leaning backwards. But the drill pattern is opposite. This is why Porsche mechanics often install StopTech big brake kit rotors backwards, despite the big "L" and "R" stickers on the rotors! They're relying on the drill pattern, rather than the direction of the internal cooling vanes.