[thegallo]

Karbosshack...I personally would go with 20's although I'm a little biased since I live in So Cal where having big wheels is pretty much the norm. I also dont have to worry about adverse types of weather that may play into performance decisions (i.e. snow, sleet, and whatever else mother nature drops on the less fortunate areas of the country). OK, off to one of your questions...The offset of a wheel (once mounted) either closes or widens the gap between the outside edge of the wheel and the fender body line. The important thing to remember is that you need to allow for the suspension to travel up inside the fender or quarter panel. If your wheels are set too far out, your tire will rub the leading edge of the fender when the suspension travels up, causing damage. Some people will roll up the inside lip of the quarter panel or fender so that they can extend the wheels as far as possible without rubbing. This gives the car a very "aggressive" looking stance. NOTE: Rolling/shaving the lip should only be done by someone who knows what they are doing and has the proper tools. You could do some really bonehead damage to your $40K+ BMW if not careful. Furthermore, wheel spacers are placed in between the hub and wheel to push the wheel even further out. So in reality if you get a wheel with the correct offset you dont need wheel spacers. Obviously, most wheel company's would rather not design a separate wheel for each type of car so they have standards which will fit most applications. Wheel spacers allow you to custom fit your wheel if you want to close the gap some more. I attached a diagram describing wheel offset. You seem to be set on the 18x8 all around for your car. I attached a pic of my car. I have 19x9.5 with +28 offset in the rear. To get that set up with an 18x8 wheel you would need about +10mm offset. So you would need to get the 18x8 with +20 offset and buy some 10mm wheels spacers. I dont know what KB is thinking about saying 35 offset will be good. That would actually push the wheels futher in than stock, that's pretty lame. I guess it all comes down to personal preference. the 18x8 with 20 offset will work for the front as well. As for the tires, 225 is kindy skinny but then again you are only going with 8inch wheels so it will be fine. I hope this helps and is not too confusing.