i'll explain about adding a new car in GTA IV   files you need from IV:   carcol.datcargrp.datdefault.datgta.datimages.txt     others file:   a new car file(wft + wtd)openIV   in this tutorial i'll be using test.wft & test.wtd as new car file and it replace turismo. if your new vehicle didn't have handling or carcol, you can use the one it replace, but rename the name to your car name(test) all words that's bold can be change to any name you like(don't use space) while editing