13.3's to 11.8's to Forget it...
With even a decent set of heads, 3.9X gears and the CORRECT converter (which means IMO 4200 would be the bottom of the RPM range and and 4500 would be better) and it's reall easy to get into the 11's.
Contrary to the common claim that displacement makes power, you don't need a 4 inch stroke to make power and you damn sure don't need more than 6000 RPM with a 3.313 stroke. And if someone doesn't like that FACT, take it up with Harold Bettes. I know he is smarter than me. He made the claim and he backed it up with SCIENCE. Of course, if you don't study the IC engine none of what he says matter.