My old 340 had the trw flat top pistons in it at first.
889g piston and pin.

This was around 1992, and there were no off the shelf light weight pistons for it back then, or Eagle rods.

I had Ross make me some custom pistons with the "max weight removal" option, and set up for .927 pins.
I also got some 75g tool steel pins from PPP, and bushed some 360 rods down to fit the .927 pins(removed balance pads, completely polished entire rod, resized with ARP bolts).

The new piston/pin combo was 525g(450g piston/75g pin.......about 3/4 of a pound lighter than the trw's......each).

I probably still have the balance card somewhere...... Iirc the bobweight was about 1850g.

A lot of weight had to come out of the crank on that one.