Aftermarket and original equipment front lower control arms are fixed length. Camber on the front of the car is controlled from the top plates that locate the struts, see here!
Adjustable rearControl Arms are a 'must have' when lowering your Mini Cooper and Cooper S. When your lower your Mini, the rear camber is greatly increased. In order to avoid accelerated tire wear ($$$), you need to correct the rear camber using Adjustable Rear Control Arms. Sold in Pairs.