this is kind of hard to explain and its not really able to be seen in a picture. I just bought a ls block with cp pistons and eagle rods in it and it was used for about 5k miles. worked great in the car it was in. he parted out the motor for money for school so i bought the block. i was cleaning the cabon off the pistons and on the back edge of one of the valve releases its not completely flat like the others theres like a little burr. if you run your hand over it you wouldnt feel it but if you run your fingernail around the edge of the valve release you will. is this a problem???