hey bro. I can give you a world of advice haha. ok...
if the wheels are 20's you may have a hard time. Read the back of the rear wheel and tell me what the "et" number says, its a 2 digit number. Lower than 32ish will probably be difficult if you want to lower the car.
Go to autozone, and spend between $50-$100 depending on brand. I have the "cone filters" setup, where its basically 2 KN or whatever cone-style filters. This really makes the car sound sick and even gives it a blow-off sound. do a search for "dual cone intake" and you'll probably find a DIY. ask me if you can't find a decent writeup.
next, I have a procede and I love it. I have never driven the car stock, but with the cone filters, this thing rips. You have all the traction you need so its a lot of fun. I raped an e46 m3 the otherday while I had 2 passengers with me. It wasnt a flyby, i'm talking back to back both from a stop and a roll.
go coilovers if you want to take care of that body roll on corners and especially if you want to drop the car. Its going to be pricey though because not many companies make them for our car.
by the way, before you mount your wheels, PM me what the tire measurements (XXX.XX.XX) are so that you don't mess up your tranny since its all wheel drive.
I'm at work but i can send you a website that checks the car's rolling diameter of the tire.
lol also, try driving the car after momentarily pressing the DTC button, DTC should light up on the dash. Its like enabling "sport traction", and the car feels great.
let me know if you need some more help, and welcome to the forum!
2008 AW/CR 335xi 6MT premium sport comfort
Procede V3|UR catless DP|Eisenhaus 2ndary cat-delete|Defi Racer Gauges|Bastuck Quad Exhaust|cone filters|KW V3| Aero lip|Vorsteiner V-35 CF Hood|Vorsteiner CF CSL bootlid|Hamann roofwing|DukeDynamics sideskirts|GP Thunders|DDM 5,000k D1S+fogs|Hardwired v1|Lumar tints