1971 340 Factory Rods and Pistons STD. Bore

you better measure the compression height on those pistons...cause all the 10.5 factory piston i ever seen only had 2 valve reliefs...

the low compression pistons usually had 4 valve reliefs...

hight compression will be 1.84 inches from center of pin to top of pistons...low compression are about .100 less...0r 1.74 inches

I think you are correct............ those look like low compression pistons used in 73......