340 Piston identification. Silvolite?

nick455440 said
pretty sure based in searching threads they are Silvolite, the only markings is the 60 over and a B296 on the inside. I came across an insane mostly Mopar parts hoard, one of the 340’s I picked up had been machined, crank turned (to not sure what) and 1.88 j heads rebuilt but I don’t think they were planned, it came with these pistons, does anyone know what these are and what compression ratio they are. Would they be good in a j head motor? What’s the ideal compression ratio trying to build a pretty hot but streetable 340

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Look for a 'SL' inside the skirt or near the pin. Its an old silvolite imo, I just sold a set like that.
th part number B makes ya think badger, but then the SL
Either way.. the pins should be thrown into the freezer before installing...or the pistons heated. Those ol Cast pistons accounted for their expansion... and so at room temp the pin wont slide right in, you can chill the pin or heat the piston to ease the installation.