0rion -
We are not a fan of the traffic on I64 and through the tunnel. Depending on the season (e.g., summer) and day (e.g., Fri/Sat) and time (rush hours) it can cost you an hour or so.
Wasn't sure where you were going, so I did some trip routing between Clifton Forge VA (on I64) to Holiday Travl Park in VB. Taking I64 its about 275 miles or closer to 300 if you take the alternative tunnel due to traffic. Alternatives bring you in on US460 -
- from Clifton Forge follow US 220 south then US 460 east. That's about 300 miles. There are navigable diesel stations on 460 at the Bedford exit (rt 122), in Sutherland (a Shell on the right) just before I85, just east of Petersburg, and just before you join US58 in Suffolk. US 460 between the 220 intersection and Petersburg is 4 lane divided unlimited access (for the most part) with speed limits of 55, 60, and 65. From Petersburg east its 4 lane divided unlimited access, just don't speed through any town with a name starting with W.
If you stayed on I64 to Charlottesville then took US 29 south to 460 that would be about 360 miles. Staying on I64 to Richmond to I295 S to 460 is about 300 miles.