Brembo drill directional

[Sterling 4.4]

Are the stock BMW rotors directional?

[chubyball]

I think there were confussions when you are purchasing the after market parts. I learned that the Brembo sells the blank rotors to the distributor, the blank one does not have directional due to the vane. After holes were drilled by distributor then they determine which direction should be.
Here is a picture of the vane looklike

[chubyball]

My brake still smell burning after 1200 miles driving with new brake, It's only smell when I done some hard driving. Is it true these cross drill rotors get hot quicker than the plain one when hard driving apply more frequently?

Thanks for inputs

[JCL]

Originally Posted by chubyball

My brake still smell burning after 1200 miles driving with new brake, It's only smell when I done some hard driving. Is it true these cross drill rotors get hot quicker than the plain one when hard driving apply more frequently?

Thanks for inputs

Yes. That may or may not be a factor in the burning smell, but they will overheat more quickly. There simply isn't the same mass there to absorb the energy. That matters more than the surface area added by drilling the holes. The good news is that after you have overheated them, they cool down more quickly as well.

[f355b]

not sure why people think crossed drilled are better than solid, i guess it must be for looks but for such a heavy car unless you go for the full big brake kit i wouldnt use cross drilled. your better off using a solid rotor and ungrade the pads IMO

[JV]

Originally Posted by f355b

not sure why people think crossed drilled are better than solid

Braking is turning kinetic energy into heat, which creates gases which need to be dissipated which is accomplished by the holes in drilled rotors.

Just ask the BMW/Mercedes/Ferrari/Lamborghini/SRT/SVT engineers who use them as stadard equipment on performance cars.

JV