I am wondering is one of the Remus or Hamman or Eisman quad exhaust can be put on the xi? I look and everthing is listed of the i. I know that the motors are the same but I want to be safe before I spent that kind of money and not have it work.

I believe you can Marquies. PM Eurocarfan. I'm pretty sure he knows of some exhausts that will work on a 530. I don't think it matters if it's an xi or not.

You can also contact Magnaflow. I know they do some custom setups for decent prices. And if you end up doing it or finding someone that has it, don't tell me about it. I can't spend anymore money on the car or my wife will kill me! :P

Now Calton you know you will be the first one I tell hahahahahaha. I will contact Eurocarfan and magnaflow. It just seems strange to be putting a manaflow in a BMW oh well it the sound is right and the price is better I good with it.

Eisenmann has a quad setup for the 530. You can also go the custom route. It'll be much cheaper to do that. Two that I know are running custom quads are Don Juan (550i) and daytrader0 (545i). Owen530i has the Eisenmann quad setup for his 530i.

Going custom what is the mufflers and tip size you all would recommend. Is magnaflow the best option? Does remus just sell mufflers?

I don't know the siz of the mufflers used in a custom setup. You will have to PM daytrader0 or Don Juan for that info. My RDSport tips are 90mm. That is a little on the large side but they look good!

tips of my eisenmann are 76mm. other option for it was 83mm. i think i shouldve gone with 83mm now that i think about it...

Cool thanks this gives me a start.