Hell, Bill Putnam (Mustang92) just made an 11.97 run just recently, and he's only pushing in the 280's RWHP.
It's not just about power. More weight reduction, better
suspension and traction, gearing, and driving ability (above all) can and will take place of simply more power.
First thing, I would build up the rear end so you can launch hard onto slicks and not worry about breaking an axle or differential. Do some upgrading on the
suspension, a little weight reduction (take out spare tire, back seats, stupid stuff like that), unhook (or better yet, remove) the front swaybar, and 12's could be yours with just some proven bolt-on mods and practice.
12's aren't going to come instantly, but some dedicated work and solid driving skill should get you there.