Do you really think $12k will get even one of the designs to the point where it can be produced?
Funding Goal: $12000(this covers the cost of CNC machining, valve guides, valve seats)
I think this means a prototype that can be put on a flowbench and tested. Production would still be a long way off.
Something to consider would be a single complete chamber 3D printed. Do your testing with that. Probably a hell of a lot less expensive than a complete billet head !
To answer the question of producing the head. Minus valvetrain, 12k gets you a set of bare cylinder head(ie cnc machining, valve guides, seats, etc). I went conservative with the goal to progress the project forward.
Also, please keep in mind that with this being a clean sheet project, I am sure there will be challenges to overcome but that is with any new project.
