New around here, my first VIP

So I just recently picked up a 1994 q45 for $1200..it was going to provide an engine for my 240sx, but after seeing the good condition it was in, i've decided to keep it and go VIP.   The only real question I have is: What's the  biggest wheel fitment without having to do extensive fender modifications?
 
Pic: [URL]http://www.facebook.com/photo.php?pid=318054&l=81c91c21b4&id=100000448365521[/URL]
 
has 236k miles, and a slight miss on 2 cylinders (probably injectors), and a crappy radio, but all in all i think it was worth it! :)

Is it a missfire? you might probably wanna check spark on that, most of my missfire issues have been the cables or a faulty post on the coil