10.5 compression on pump gas

I have 9.8:1 compression with aluminum heads, smoothed chambers/edges/spark plug area, chamber fitted to bore so no overlap. Flat top pistons with quench around .030, IIRC. 63 ABDC on the cam. It's got a Dynamic ratio of 7.86

I run California pump 91 octane. In my 416 it will ping at 4000+ rpm going up hill accelerating at hard throttle. I've got the timing at 30 degrees total and run Autolite 3924's