Im looking for some true numbers, i have a b18c1 block and head. I needed to bore the block +25 over and had to mill the head .0010". Now my question is i want to use +25 CTR pistons& rings but someone told me the com. would be to high. and i wouldnt be able to tune it. I know that if i use ITR pistons i will have no problems. if anyone is using CTR pistons in a b18c1w/ a gsr head let me know.