You might want to check your particular engine before taking off that much anywhere. There is a lot of variation in chamber size, head gasket thickness, etc. Has the deck or head been machined before? A cleanup pass on the head will take up some of that, and a pass on the block a little more.

It would be easy to mill yourself into a higher octane fuel requirement, something a daily driver doesn't need.

By the way, it wasn't just sixes of the era that had low compression ratios. There are lots of four-bangers and bent-eights with similar numbers.

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"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO