I believe 650 CID is about it in a raised cam siamese bore hemi block, still going to need a dome to get over 9 to 1 compression or so. I am not a total purist as some here would believe so I don't think it would be a sin to fill in the sides of a hemi head a little like the eagle, apatche, and 6.1 heads in order to get more compression with less dome. It can certainly be done without hurting the flow.

Also the chevy heads in this discussion are not wedge heads no matter what universe you are from. As far out of kilter as those valves are I would not even call them a twisted wedge, as a matter of fact the more "Hemi like" they keep making these heads the more flow they keep getting. They are splayed valve heads and they still need a BIG bore to match the flow of the Hemi valve arrangement (witch is the real important part a lot more than the chamber shape)

Of course none of this matters to the discussion because the Hemi is not allowed in the guys class wonder why