I'll look up "516 casting heads" and see what I find. This site is great. I'm trying to edumacate myself, and you guys are fantastic. Thank you.
As for compression, I understand if the combustion chamber is increased in size, that would lower compression. Does the ratio, for example 10 to 1, mean that the volume at tdc is 1/10th the full volume. In other words if each cylinder is 55 cubic inches (440/8), and I know the compression is 10 to 1, is the tdc volume then 5.5 cubic inches? If so, with a flush piston top obviously all 5.5 cubes are within the head itself, whether it's dome shaped or whatever. Which leads me to a question of the size and shape of that volume, which is, other than stroke and bore, a very important variable, and obviously it is that little volume and shape that is the subject of lots of bragging rights throughout the years.
Since it is a closed chamber head, I have heard those are not as efficient as open chambered, but I guess it depends on the application. I dont understand the difference between the two, but thats the type of thing that probably needs to be seen to understand. Reading about this stuff is not the same!
Thanks.