We also may or may not have broke pistons in multiple stock motors..........But the good news is it would appear that the stock ring gap is not enough for 22# of boost. Both motors we measured ring gaps between .014 and .016. We opened that to .022 and .024 on the forged pistons. In hind site had we taken the motors down and re-gaped the rings we likely would not have had any issues. Unless the junk yard motors already had issues we were unaware of.