I know of a few guys who have gone 11s on stock motors with power adders. Im sure a good cam, stock heads, intake and all the bolt ons on the right car could get you deep into the 11s!
definitly possible with stock heads and maybe even stock cam, but u have to be ready for the bottom end to take a dump if its got high miles and ur pushing at least 12+ psi of boost intercooled or not, the stock 2 bolt main and stock rods cant hold up to that kind of pressure for long.