B-block cylinder heads?

I wouldnt use any -1EZ based head on a 383. I'm guesssing at some point you will need to make power below 5000 rpm. Those heads are way too much. The std port window SR EZs are even a little much for a 383 IMO, and those are the lowest flowing aluminum heads Indy makes. I would be looking at Edelbrocks for a cost vs return standpoint, and the fact they will flow enough air in modified form to feed a 600hp 500+ inch engine. The heads you are looking at will make more hp at peak, but peak on that 383 will be close to 8000 rpm depending on the cam selection. As far as Hughes, buyer beware.