While that is a lot of dome above the deck, that's not what they called a 12 or 12.5 piston. Those are more like 11 or 11.5. The true 12.5 pistons have a massive dome that's so big it has to have a spark plug groove cut into the middle of the dome and those do not. While I'm sure you can get 12:1 or more, those do not have the dome that the true 12:1 pistons had. Here's what the real 12.5 340 pistons look like. There's no mistaking those.
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