I agree, Charleston is a must see. A wonderful seafood restaurant is The Boat House on Isle of Palms, crab cakes and stone ground grits, mmm, mmm! The view is awesome too.
Also 2 hours away from Charleston is Savannah, GA. Home to Paula Deen's restaurant The Lady n Son's. Surely if you like southern cooking you know who Paula Deen is? If not, check out the food network.
Asheville is nice and if you like history, The Biltmore Estate is the largest home in the US. The construction of it is quite impressive.
BILTMORE in Asheville, North Carolina, Americas Largest Home and More!
Ok, now down to more serious business, NASCAR. Lowe's Motor Speedway, for $5 they'll take you for a hot lap around the track. If you pull up in front where the stairs and flags are, there is a gift shop and ask the person at the counter as they will give you a list of directions to all the raceshops.
Hendrick is just up the street from LMS and they have Schrader's Budweiser car that he rolled at Daytona years ago, unfortunately they took down the photo they showed the sequence of the accident.
Rousch Racing also has a nice museum. Richard Childress Racing is quite a drive but if #3 was your fav then you must go. I believe they charged $10 to go through the musem but it was quite impressive with Earnhardt's car from his 1st Daytona win and they actually have his hauler on display, that's a lot of money sitting there. But very nice.
You can do a drive by of the new NASCAR Hall of Fame in uptown but don't think it opens until next year.
Hope you have a great time. Oh and yes the first time I did the race shop tour I walked away with a purchase from almost every shop, including lug nuts from the number 8 & 24 cars.

Yes, I've got it bad...