Need A8 Rotors

[Larry C Leung]

Slotting (a.k.a. Gas venting) and drilling is done to allow the gases
that occur in VERY HEAVY braking from the brake pads to exit the braking
surface without acting as a "lubricant" between the pad/rotor interface.
A side effect is it sometimes helps remove water from those very same
surfaces when the rotors are wet on intial application of the brake. Once
the rotor has made one turn, water would be removed even from standard
rotors. As pointed out, the removal of mass does effect the efficiency of
the rotor's heat absorbing abilities, but if you are in racing or other
"high performance" applications where the pads will constantly outgas
anyway due to such high temps, then the loss of mass is offset by the
removal of gas. Otherwise, gas or cross-venting serves little purpose
other than to look cool. BTW, I have heard that most Porsche racing teams
remove the street cross-drilled rotors on their race cars and go for
smooth ones for durability and rotor temp reasons. If you use a suitable
pad that won't vent gases, this certainly seems to be effective enough.

LL -  NY