Have a 2008 3.0si Z4...and interested in moving to an Afe cold air intake. OK, its a bit sophormic but this will probably be my last roadster and I want to make some changes..but here is question: it would seem that a conical filter, and they have fine ones by all standards etc, still lets air down center, which seems to be unfiltered. I think I am missing something...and interested if anyone can clarify. It would be the stage 2, only one available for this later Z4si. And can anyone also clarify what MAF sensor does and would it be affected by putting into the new tube config?? I need not have lights come on just to justify this increase in whooosh etc...thanks for any technical info anyone can provide or anyone who has done such---I am grateful.