Which HIDS would fit on the A4 without mod'ing it? what size is the stock housing? would something like the audi TT HIDs fit? And another question, I really want the fog lights from the 1998 and up, would they jut bolt on to my 1997 a4

 

Please do us a favor and search before asking questions.

The stock size are H7. I don't know of any kit that wouln't require modding the housings. Yes you can retrofit 1999.5 and up fog lights (not 98), but it requires custom brackets, cutting of the bumper and rewiring. I've did it to my B5, it took about 3 hours of labor. Wasn't really worth it in the end.