alright heres the thing, im putting together a motor and i had a gsr bottom end bored out to a set of itr pistons that i bought and i had the bottom end completely balanced and the crack knife edged. The cams that i want to go with (skunk2 pro2s) i would like to up my compression to get more power out if my cams, so would i be able to just drop a set of ctr pistons right into that bottom end without any troubles or are the bore sized different or will it throw off the balance of my bottom end...please help me out asap!!!

 

Your cylinders should be bored/honed to the pistons' specs to ensure proper piston/wall clearance.

 

well do ctr and itr have the same bore size i guess is what im asking

 

Standard ITR and CTR pistons are both 81mm, and are also available oversized for rebuilds. However, even with pistons of the same diameter, the actual measurement of each individual piston can vary, which is why each cylinder needs to be bored/honed to its specific piston.

 

whit ctr pistons your compression would be 12.042422. that's whit oem head gasket.