Mystery 318 wants 30* initial timing?? Pinging hard

Thanks for all the suggestions.

nm9stheham said

So what vacuum levels DO you have?

Is this 318 stock or modified? If modified, what mods/parts?

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It is modified. Internals unknown, supposedly rebuilt. It has 302 heads, 273 rockers, RPM intake, thermoquad 9800s, headers and dual exhaust. About 15" of Hg at idle