you can't put gsr rods and pistons into a b16 block they'd stick out above the deck by something like 4mm
you can put gsr pistons on to b16 rods that'll drop your compression to 9.09 :1 which would be nice
if you want a 1.8l with oem parts buy a 1.8l block. you can't achieve 1.8l from a 1.6l with oem parts, you can however bore it out to about 86mm and get close to 1.8l (1798.6cc) but you can't use the gsr pistons nor any other oem piston, and you'd have to sleeve the block. an 87mm bore (which is the limit to boring honda's i might add) would put you into the 1.8l range (1840.67)
with the boring and new pistons to fit in the block that'd cost you more then just buying a 1.8l block to boost, i'd say just boost the b16 with or without the gsr pistons it'll still make good power even if its not 1.8l
