High Compression 390

I do not know where we are on this but
too bad there are no heads between 3 and 30 cc (est)
I don't mind 10.5 with 87 or 11 with 91 at altitude but I'd build for 87 and run 91 with a load or if going flatland
I do think the quench at .050 + .010 is way more than I'd like to see
and no way with the open chamber heads
you can open the chamber around the intake with the valve guide machine and pick up 5 cc
put the heads on the bare block and scribe the bores then open to the bore the flow prefers a match - do make the chamber larger than the bore but sometimes they are that way already (thinking big block here) if the chamber overhangs the bore chamfer the top of the block
keep working with Lunati you are close depending on which way the compression comes out