I really did little to change the shape of the actual combustion chamber.
I mainly removed ceiling imperfections and sharp ridges right around the plug area. Anything that could create hot spots or irregular airflow.
There was a slight compression "ridge" that I removed and made symmetrical with the area around the adjacent valve.
The heart shaped hemi spherical chambers are quite efficient.
I did the least work "comparatively" in the chamber. Mainly all the detail work in porting. I did little shaping outside of smoothing and unshrouding the valves to the optimum measurement.
I figured my final compression by CCing the chambers and doing the math.
I could see going a little lower compression with some more judicious work in the chamber area.
IIRC Jesse has ported the chambers like I am talking about. Tapering back the sides for a forced induction build.
