You should be able to tell by following the brake lines under the hood near the firewall. If they run to a little box on the passenger side, then you have abs. If there is no little box, then you dont. Also, check to see if you have an ABS fuse. Im not sure about s13's..but when you start the car on s14's a light comes on that says ABS or ANTILOCK or something of that nature
Edit: oops...i guess i should read the rest of your second post before answering.....oh well...at least I gave you a correct answer <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt='

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