So I was thinking about putting an s15 cluter in my s13. I read the post before me, talking about needing a s15 engine/diff/etc...but it seems nothing was ever actually solved, just argued, and no real ending to it, lol. My friend has a s15 gauge cluter and ECU (whatever that means?) and he said he would sell it to me for 190 bucks. So I'm just inquiring as to if you ACTUALLY have to have an s15 differential...etc...and to if this would actually WORK in my s13.....