I have call of duty black ops data and map packs saved on my hard drive but the disc was scratched and I'm thinking of downloading it on Xbox Live but will it erase my data and will I have to download the map packs again
It shouldn't affect your add-ons what-so-ever. If you have previously installed from the disc, you'll want to delete that version so you don't get confused when trying to play it out of your Game Library. Happened to me when I bought Bad Company 2 on demand!
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