I know of a Challenger, street trim, 500"BB, OOTB Eddys, relatively small cam, 727, 3.23, 28" tire, that runs in the 11s. Shifter in D. Hardly trying, so to speak.
Seems for a SB combo to pull that off without more converter & gear it would have to be WELL into the 400" range.
It's gonna take a lot of torque to pull that tall gear into the 10.50s.
Now, if the car could be lightened up a bunch, or you could live with more converter & gear, a big SB would close that gap some. The turbo or Vortech path is also a valid consideration, but hurts the bragging rights if you know what I mean.