RE: cast crank motors

Sounds like you are owner of a non-molested car, that's great. The engine ID pad on top front of the motor will have a bunch of numbers/letters stamped into it. For example, I think your engine ID should start out with G383. If the engine was built with a cast crank there will be an "E" stamped into that pad, either at the end of the number or sometimes off by itself. There may be other markings too. This engine ID tells how the engine was actually built. This information is easily found online.

For example, it could have undersize rod and/or main bearings or an oversize lifter, all from the factory.

R.