From what Ive come across, theres really only 3 main differences between the LS2 and the iron block 6.0s...
Price, the iron blocks are about half the price
Weight, the LS2 is about 100lbs lighter
Overbore, the iron blocks can be taken out to 30 over if damage ever occurs, where as the LS2 cant...
Some will say that there is a strength difference, but for the power that you are shooting for, you wont have to worry about that.
Im using an iron block in my regal too. Im going to be pushing it a little harder though and like the idea of a future overbore, and in my mind, iron will always be stronger than aluminum
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