With the garbage they sell as gasoline now days, you need to be reducing the compression to a lower level IMO, no way in the world I would run a dome piston and a open chamber head.
Why not, if the compression is dropped to a suitable level?
Wouldn't a closed-chamber head have a higher CR?
I'm thinking I can get this combo down into the 10:1 range...even if it means shaving the domes.