It's pretty easy to make a 320iS look-alike. The major differences are as follows: -Recaro interior -Limited-slip differential -13in. basket-weave BBS-style wheels -rear designation delete -rear sway bar (16mm) I'm not sure if front/rear spoilers were optional or not, and there are rumors that the suspension was sport-tuned, but I've never seen conclusive evidence of that. "s" models also came standard with many optional things on a regular 320i - sunroof, dual power mirrors, fog lights, and some other things. I'd look for most of those things, and if you have the majority of them, it'd be safe to say you have a real 'S.' I'm sure someone knows if there's a code diffrence in the vehicle number, but I thought I'd ramble on for awhile. Hope it helps! -alan 83 320i 79 320i 74 02