autoxcuda said

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

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clinteg said

Now that is very surprising that you get any sort of pinging considering your setup you've described. Any reason why it would do that with the DCR and SCR that low?

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