I assume the measurement is from the center of the piston pin, so distance from top of pin hole to top of piston + half the diameter of pin hole, right? I'm trying to find a set of low compression pistons for a Blown 440 project and the ones I have measure 2.071 using the above method. I'm thinking these are not the ones to use. Thanks!

yes that is correct, the CH is from the center of the pin bore to the flat surface on the top of the piston. though it's splitting hairs measuring from a round hole is subject to slight errors if the correct tools aren't used. using the CH you listed, a stock deck height of 10.725, stock stroke of 3.75 and stock rod length of 6.765 your .014 in the hole. you really need to calculate the CR taking the head volume, piston reliefs and or dome/dish (if any), deck height and head gasket volumes into consideration. here's a calculator to help... Compression calculator

And if you really want to get to the nitty gritty, the area between the top of the ring and the head!

Kool! Thanks guys. These are just stock replacement pistons, I wanted to find out if they're the 8 to 1 or 10 to 1 variety. Looks like they are the higher compression version. I'm thinking I might use them in my street car. Do you think it would be a good idea to machine the block for zero deck and use these with my 915s? are these good pistons to use in a quench motor? The only number I can find is B278. I'm thinking they're Badger?

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And if you really want to get to the nitty gritty, the area between the top of the ring and the head!

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look at the calculator smartypants it's in there


as for what to do with those pistons it really depends on your goals. no matter what you should do the math to see exactly where you'll end up before machining anything.