For some reason (dain bramage most likely) I only just now noticed that the Acura manual shows an index mark for aligning the brake rotor on the studs.

I dont think I have noticed or paid attention to an index mark.

If I re-installed rotors after some work but put them on w/o matching the stud-index what will that cause?
(I have a shudder but I will start a properly titled thread on that issue after I get an answer on this)

1991 GS 2dr

 

will putting it on mismatched cause warpage?

do after market rotors even have an index mark?

and the craziest question.... should rotors be removed/installed with consideration of the stud positions???

 

Im preety positive there is really no incorrect way of installing your rotors,unless you try an put em on back word.now there are two holes were a 12mm bolt can be screwed in to help remove the rotor w/o beating on it with a ball peen hammer... those holes I always make sure line back up with the lil mark on your spindle, other than that its preety straight forward, now if you replaced the pads without resurfacing your rotors that will deff cause warpage/runout....

 

If the rotor was turned on a on-car, wheel lathe, it should be reinstalled in the same position. In an ideal world, it shouldn't matter.

 

does that mean if I take my rotors off to have them turned it does not matter?

 

It shouldn't matter. Make sure the hub face is clean and check the rotor for run-out.

 

ok I guess your helpful answer actually gave me another question, since I have never heard of on-car lathes (though it makes sense) maybe this should be it's own thread

what are the pros/cons of on-car vs off-car rotor turning?
and how real are the differences?