Icon forged pistons

Guitar Jones said
From Hughes engines site;

KB pistons

C.D. Approx. Weight Pin Size CC's Comp 64cc Comp 68cc Comp 72cc
1.465" 638gr .984" X 2.750" -20.5cc 10 9.6 9.3

Diamond pistons

C.D. Approx. Weight Pin Size CC's Comp 60cc Comp 65cc Comp 70cc Stroke
1.457" 502gr .984" X 2.750" -20.0 10.0 9.5 9.1 4.00"

So 136 grams is laughable?

I'll bet that Diamond piston weight is without a pin. There's no way your going to get a typical shelf 408 piston down to 500g with pin. Double check that there mr. jones....