Honestly, if you're barely driving it an ECU swap is waaaaaaaaay more expensive than you need to go. Just look at getting a set of K&N Drop In Filters, a set of Z1 Post MAF Tubes, and a CBE. That will put you in the same arena as a Nismo, still looking stock, and if you'd like, get it tuned as well. All of this will cost you less than an ECU swap. Unless you meant ECU swap = Tune?