Worst engines ever.

400 pontiac. (cast crank, cast rod, KABLOOEEE)

It may not have held together real well under a high hp application but they weren't bad engines. I had a 72 Grand Prix that ran 13.90's consistently with a mild low comp. 400. I spun it to 5400 regular and never had a problem with it coming apart. It was built right though. Arp rod and main bolts and everything re-sized. That helps a bunch.