IMO, just changing the head unit to a decent aftermarket will do wonders. I wouldn't bother running a sub off the factory deck. I have a good Pioneer deck running highs through the factory amp (I have the same system as you), and RCAs to a cheap 100w amp and a cheap 8 in a custom box. It sounds 10x better than the factory.
Scott __________________
1998 318ti base that appears to be moulting |