Going to Build 470 Street/Strip Engine for 71 Demon

I have checked Ross but looks like self models rise comperssion too much for pump gas as those are just 4cc dish. I have 6.700 Rods so pistons should be 1.32 comp height and about 8-12cc dish to keep comp around 10.5 - 11. Bore will be 4.375.
What's your pump gas in Finland.
People run 93 octane up in the 12.s for compression