I drove out to Wyoming from Virginia and back several times when I lived in Jackson Hole, Wy. (a distance of 2100 miles) - 3 days there, and 3 days back - just me and my dog in a 1972 Chevy. I have also driven from Florida to central Va. numerous times and the distance is also exactly 800 miles one way. The 800 miles can be done in one day with one driver, but you will need rest breaks so account for that. A lot depends on your route - mine is mostly interstate all the way. Also, the gas shortage thing is nuts in some areas, so check ahead to make sure you can fill up. With rest breaks, I can drive the 800 miles in about 13 hours. It is a big trip for only 3 days, but I know how it is when you want to see your family - it will be worth it. And your car should do fine - it is hard to stop a Volvo!
“No Bird Soars Too High If He Soars With His Own Wings” ~ William Blake