This really saves on buying an X or R block.

People should not confuse themselves into thinking a oem block can even come close to what a X or R is or can take.

The main webs, the filled inner pan rails, the thicker decks, cylinder wall thickness. The nickle content.

From side by side on a stand compassion to parts attrition on freshen up its all easily spotted.

The main reason we see x or r blocks in these times that cant go 4.100 safe is because they are seconds from the days when they were easy to get and were set aside from core shift as culls.