Higher compression octane requierments

Lefty71 said

Anybody have a link to a meaningful chart showing octane requierment at a given compression at a given temperature. I'd like to find something that uses cranking pressure as a baseline, if such an animal exists. I know the calculated static and dynamic compressions for the build, but the cranking pressure is more of the reality, if you know what I mean. TIA, Lefty71

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There is no such thing. Cranking compression means nothing, unless you have changed cams in the same engine, and even then it's nearly meaningless.

You can run 12:1 on pump gas and not have issues. You can have 9:1 compression on pump gas and it will rattle it's brains out.

It's all about getting the parts that work together before you start the build.