Permissible block deck distortion

does anyone have a good info about permissible 5.2 FSI block warpage? How much is too much, and what to do if it is out of spec? Machine the block, just like heads?
I know warped blocks were much more common with S4s

Yeah very common on the 4.2 S4s not so much the RS4s. I don’t think I have heard of any on the 5.2 due to it being the next gen blocks in the all aluminum block group