I-85 to I-77 to I-81? If so, be aware that this board only covers the GA, SC and NC portion of your trip. For the rest, you'll need to post on Mid-Atlantic, Pennsylvania, etc.
Any particular type of food, restaurant or price range you are interested in? How far off the highway are you willing to go?
If you do a search for the highway numbers and towns you pass through, you will no doubt find lots of previous posts with useful information, for example:
Near the intersection of I-77 and I-40 in Cleveland, NC is a wonderful roadside shack called Keaton's. They feature a delicious and unique style of BBQ chicken.