Are you sure??
These are brand new, have 2 valve reliefs in them, and have never been milled off. they have p2332 .030 on them. They have a slight chamfer on the edges of the top, and they dont look too bad at all. The similar piston for a 273 or 318 says 9:1 but I cant find anything on these.
I have a set of the 12.5 to 1 pistons in a dirt track 360 Hermaphrodite engine we ran for a while and those were milled off so they were legal. This piston looks nothing like any mill marks on it, and is tas a funky center hole in it that from what Dan at performance only and I can tell was used as a centering device to chuck the pistons up with.
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