How do I prepare a RBG jpeg picture to print 8ft/12ft from illustrator with out lossing its quality? I simply need to export as a pdf file

I recently ran across an article in a PC Magazine about freeware. There is a free program called Rasterbator that will create a PDF file for your image. It tells you how many sheets are required for the image size you choose. Unfortunately any time you blow up an image that large you can not avoid losing quality no matter what software you use. The Magazine article included a link.

The Rasterbator 1.2 at arje.net

Check it out.