Since it looks like your working with WAV files instead of MIDI, it's going to be a bit more time consuming. If it was midi with sampled drum sounds, then all you have to do is adjust the tempo of your song and it will adjust with it.
If I am reading the site right, and these are .wav files, then your going to have to timestrech each one in cubase and assemble them. Or if you are able to set up the whole drum track first and then timestrech the whole thing, but that is going to take a lot of time depending on the speed of your computer. Your easiest bet is to find the loops that have tempo's that match the songs you are trying to do so you don't have to timestrech at all.