because of the way the group works or use to anyway. If a certain section of the group develope a part they have rights to use it for a short period of time exclusively. Also Audi wants to use variable valuve timing on there units were VW will use the standard units to help seperate them. Its a siimilar principle to what the fiat group do with Fiat and alfa (alfa uses twinspark heads).so what are the changes under the hood? I hear it's an increase of 7 horsepower which sounds pathetic. Why not use the new 2.0T from Audi that they put in their new A4? It has something like 220 horses and a shit load of torque.