Strong short block

600 hp is more than a stroked stock block will handle for any decent amount of time. Their just not that strong. As YR said you can hardblock it to add strength but if you run it on the street you better live in AK or northern Canada you'll have major cooling issues.

BTW: the only stock production block that's better than the rest that I know of is the T/A block and you'll pay out the nose for one