If they were the 2295 "12 1/2" (ha ha ha!) pistons, they were a bunch, a BIG bunch under 12 1/2 to one. Blueprinted deck, maybe 11 1/2. Thrown together, likely 10 1/2.
I have some real 12 1/2 arias, that have three times the dome of a 2295, and the are still down in the hole enough to be 11 1/2 to one.
