Probably in the low 8's. Theyre basically smog heads with screw in studs and some other improvements. You can occasionally find a set of new heads off of a goodwrench in the trash. Ive tossed a set myself, and the so have a few other people on my street every now and then (should give you some idea of what they're really worth

). For free, you would probably just about get the same result. Runs, but goes slow and likes to ping from my experience.
If you actually want to get decent performance, look elsewhere.