a WAV file conversion from mp3 will increase the size of the file.
best thing to do is listen to the music and note where there is a fade-out between 500-700 megs, then split the file there and repeat at 1000-1300 megs.
sounds like you have 170megs, so you should expect to have to burn 3 cds to get all the stuff you need.
I use an audigy sound blaster card with a creative play center editing and can actually see where the sound wave diminshes, and can in fact, fade out any sound by using a toggle lever like a real sound board.
what you really need is software that allows you to split the audio file into pieces. google should help with something searched like ("split mp3 files" + "software").
i just found 6500 hits doing so. at
http://www.google.com/search?hl=en&q=%22split+mp3+files+%2B+%22software%22.
the other possibility is to burn to a dvd which has 1-2gigs of space, but then you have to consider how you can play it