That was me branching. Lol. I like the idea of a radius under the seat I think Mopar used to sell some seats like that , I know somebody did or does still. When you bring the valve up 300 lift and you have that 30 and 15 it looks real nice against it. and I believe that picks it up there. Now back to that crisp top cut, the lip on the short side chamber, it gets in the way for milling! Lol you can knock that off, put the out a valve job lower and not lose and maybe gain in peak even. You'll never get a j head to sub 64cc with that 30* funnel at the top. Material permitting, I think the exhaust would do better lower too. Not buried/sunk, just with the material for the angles and where the spent naturally wants to go into the higher hole so to speak. Lol