426 Crate Motor good or not?

Well considering world cast blocks have a 50% failure rate i would be very worried. Core shift so bad cylinders would hit WATER if bored the "supposed" safe, porosity issues so bad OIL leaks into the water jackets, water passages blocked by sand.

Besides all that those are street hemi's. You can build a hemi from the ground up for about 16K (single 4, not a mag crossram/correct carbs/linkage/etc) and it will be a streetable RACE hemi that runs on pump gas, runs 10's, and is a great motor...