6-71 small block build.

I found a set of J heads for cheep (local). What are you guys thoughts on running those on this build?

I believe they are open chamber so that's good. They are cheep so thats even better!
2.02 Intake valve.
1.80? Exhaust.

That's a good pickup. My way of thinking is the heads are the least important part of a blower engine. The intake runners on a set of J heads are plenty big enough to allow more fuel/air into the cylinder under the pressure of a blower than what they can really handle. Remember that boost is really a measurement of the pressure of the air/fuel that didn't make it into the cylinder. I believe you are much better off spending the good money on a proper cam.

Jack