I think Im suppose to bore the 5.3L out to 3.910 is that correct? I know the LS1 is 3.900 but isnt the hole slightly bigger? I have a LS1 alum block but its cracked and wanna transfer everything over to the iron block. Thanks need help asap!

 

The only right way to do this is take the pistons and the block to a machine shop and have them machine the bores to the pistons.

 

alright, thanks