The iron head? I’m sorry, I really don’t know. Call ProMaxx up. They were really good to talk to on the phone. FWIW, I’d buy from them again.
The aluminum head? Yes. They get it bare and work it from there. There CNC port job on there Maxx series doesn’t address the short side, the port floor is largely/mostly/completely (?) left alone, so there is a lot left in the head flow wise. A quick glance (@ best) is all it got from me. It looked as cast. I really didn’t G.A.F.
The work is what I’d call a safe porting. It’s not a full blown porting. You can absolutely build a quick car with those heads.
