9:1 CR for KA24DE-T These are Forged pistons. We are now stocking the 9:1CR. Kit comes with piston pins and piston rings. These are the same CP Pistons we use in our Time Attack car that took 2nd place overall in the Redline Time Attack Series. They have held up to the punishiment we have given it and never had any problems. We would recommend this over any piston since we have first hand experience with them. Good high boost levels.