[s-cars] Slotted Rotors

[KBATTPO]

Greg Johnson wrote:
> 
> OK, it's probably a silly question, but for those of us that are or have been
> thinking about using slotted rotors on our Audis,  which way do the slots go?
> Assume you are looking at the rotor face (front).  On one rotor the slots are "back
> slash"  \ ;  On the other rotor, the slots are front slash /.   Which rotor goes on
> the left side

The "/"

> and which goes on the right?  

the "\"

> Does it make any difference?  

Absolutely. The slots among other things facilitate water evacuation.

> It would
> seem that in one instance the squeezing brake pads will cause the gases and/or
> moisture to flow towards the hub and in the other instance they would flow towards
> the edge of the rotor.  Which is better and why?

Outside. You do not want to force the water inwards by the Coriolice
force of the cut grooves so that it fights the Centrifugical force
caused by the water-to-rotor friction.

Igor Kessel
'97 UrS6, slotted as per above
'98 A4, sucky big time non-slotted brakes