All BS aside, LS blocks can probably take more than any other block ever built. I have never seen a LS block fail and have never heard a credible story of one failing. Any time you hear a LS block failure story... There's more to the story (bad tune, machine work, ect). In the early days guys would stroke stock blocks past 4" and pull the skirt out of the bore, the piston would become unstable and take the block out in the grenading process. With stock blocks being limited to 408"ish, it's basically impossible to build enough HP to break a block N/A. The turbo guys routinely turn 1000+HP on stock blocks. I can remember 3 separate LS destruction test done by magazines. I know one was called " the big bang". One was a 4.8L junkyard short block turboed to over 1200hp and 60+ dyno runs...No failure. Second was a 5.3L junkyard short block turboed to over 1300hp and 70+dyno runs. A lifter failed, they replaced it and lived again. The third was a 5.3L junkyard short block spraying rediculous nitrous. They had a multistage progressive system with awesome tuning. They sprayed until the HP wasn't increasing anymore. The motor couldn't ingest anymore. It was actually flowing out of the intake and filling the dyno room...No failure!
