How far in the hole?

You don't think the advertised compression is what it's actually hitting, do you?
I'd bet they're .060"or more in the hole.
Off the top of my head I don't remember, but 318s are typically like .080" down the hole, and even the earlier pistons are only like .015" taller, IIRC.
I'm sure someone with better memory, or better versed on this will confirm.