front tires are 225/45/ZR17 and rears are 245/40/ZR17. This is because my front wheels are 7.5" wide and my rears are 8.5" wide so i need different size tires to achieve near equal sidewall height.
look at the pics of my car here:
http://picasaweb.google.com/iamthenomad/MyBMW
I have labelled the pictures to indicate which ones my car is lowered with the H&R OE springs and which ones aren't.