This OE can only be retrofitted via an IBAC code which is created by BMW headquarters and sent by e-mail (Attention: IBAC code only valid for 30 days after creation): - Order the specified part number and send an e-mail with VIN und Retailer number to: parts-and-accessories@bmw.de ***** ***** ***** ***** Performance Control increases the agility of your motor vehicle. To increase manoeuvrability, with appropriately sporty driving style, the inside-curve rear wheel is decelerated and the resulting braking effect is also compensated for by engine intervention to a large extent. *****