I have some JE forged pistons and Crower Rods and I was wondering if I can reuse them in another block if the specs are the same in the new block, or is the integrity of the materials compromised?

 

are you saying they have been used already? its not clear exactly what youre asking...if they are going in the same block and youre using the same crank there shouldnt be a problem, if they have been used as long as they havent been damaged it should be fine