If we go 6-2 like you are suggesting, with a win over Va Tech and a loss to FSU, we are more than likely going to have to win a tiebreaker to get to the ACCCG.
The two biggest hurdles, of course, will be Va Tech and Miami. Miami's remaining conference schedule, in order of hardest to easiest (IMO) includes: @UNC, Clemson, @Wake, UVA, Duke.
Check out Va Tech's hilarious joke of a conference sched excluding their game with us: UNC, BC, NCSt, @Maryland, @Duke, @UVA.
Given their schedules, it seems to me that it's equally unlikely that Miami will go to 5-3 or that Va Tech will go to 6-2. If lightning strikes and both those things happen, we'd win any tie-breaker scenario, either head-to-head or with multiple teams.
If we get to a 3-way tie with Va Tech and Miami, with each team being 6-2, and with each having both a win and a loss against the other two, then it will come down to who has the best record against Coastal teams. In your scenario, we'd be 4-1 in the Coastal and thus could not be eliminated by that rule. Ideally, Miami would have lost to UNC, eliminating Miami and getting us to a head-to-head with Va Tech and/or UNC, which we win.
Beyond that, it's pretty complicated and can have to do with overall schedules and even BCS ranking.
Bottom line: It's really gonna be tough for us to win the conference at 6-2. Our best hope to win at 6-2 would be for Miami to implode all the way down to 5-3 and for Va Tech to get stunningly upset by someone, and that's assuming we beat them.
Given the Hokies' joke of a schedule, it is not an overstatement to say that if we don't beat Va Tech, we have almost zero chance.