Yeah I think we whacked at least .030 of the top of the BBC slugs, they were OEM (maybe what? 7.8:1) 454 slugs straight out of a junked mid 70's suburban.

We tried to do the math to make a 383 rod work but there was nothing even remotely close. I think we ran .060 copper head gaskets, it was definitely a frankenstein but it ran like a scalded ape.