Front Rotors - Left and Right?

[NRuest]

On the EBC site I am seeing that there is a part number for a left and a right rotor. What would be different? They look the same to me.

[jwd98056]

According to the BMW microfiche there are two different part numbers for the left (34112314893) and right (34112314894) rotors up to 1/2001. After that date they are the same part number (34112338228) at least through 11/2007.

[firstbeemer]

Just a thought but maybe the one side includes the ABS ring.

[murray]

The breaking system's may require different rotors due to the integral system 02 and up. The rotors are directional sensitive related to the drill pattern. So note this before the install.

[NRuest]

Pete, good catch. Now that I am looking at the drill pattern on my 2000 I see that they are definately directional. See photos

The rows alternating of 3 and 4 are angled to the rear starting from the inner edge leading back to the outer edge. The newer rotors are symetrical and could be flipped without changing the pattern direction.

So the question then is are rotors from 02 and up interchangable with the earlier years or do they match up to the style of caliper?