400 engine

prine, wrong the 72s have the thickest main webbing of any factory block manufactured,the bore thickness is the same, the webbing on the mains on the later blocks and stroking a 76 or later block to make big hp requires block filler, bore thickness is same on all maybe better moreso on later 400s as technology advancements in that time frame created better and heavier blocks and less core shift .regardless, the 78 blocks are better than the 383s and 440s with the exception of the 76 4006630 440 with .575 meat around the main but not all these blocks had the .575 but it sure beats the .375 number for older 440s