If I delete the raw video on my hd will I lose the projects i am working on? The clips/viz showing on my timeline are only links to the raw viz correct? I want to free up some hard drive space so any suggestions would be appreciated.
Yes you'll be fine. The project file and the media are two seperate entities. Hence why its far more valuable while editing to always be saving all your copies of your project files. If you lose the media you'll lose a lot of time to re-digitize it, but if you have the project file, at least you can still re-digitize it.
DO NOT DELETE your source videos unless you are sure you do not need them any more. The Project file will not work without the source files (in the same original location)
The Project Window and the timeline are only references to the source files as you assumed (correctly)