Another piston option for the 273.
513 grams for the unmachined 9115 pistons and 95 grams for the pin = 608 grams total. That compares dang light versus the standard piston+pin weight of around 750 grams. Drop another maybe 120 grams with SCAT rods.... and probably 10 grams or so off the rings.
Bobweight then becomes around 1791 grams before machining anything on the piston head....nice. (Stock 273 bobweight is around 2147 grams.)