Need help with Insane 340 setup.

Well I just weighed the TRW L2322 dome pistons, the pin weighed 154 which seems right but the piston weighed 637 which seems really light for these pistons. Granted the dome was milled down alot and it looks like alot was taken off the underside but I thought these were in the 800g range stock, I was thinking about the 2316's which I've heard are 735g. Anyone know if enough can be taken of the 2316's to get it to 637g from 735g? Heres some pixs, also look at the one piston, looks like the edges were melted and the ring broke off in it, amazingly the bore was not messed up, go figure...

Butch