It originally came with a 350 rocket 1971 but i think the engine was swap for another 350 later year how can i determine what year is in there now?

 

The casting number reads 557752 big3B

 

Hey, Click on the Olds Junction or Tech links at the top of the page and all that info is there, it has the codes and I.D. numbers and how to tell what year it is, along with a lot of other very useful information.

Acccording to that that you are correct and it is a later 350 engine.

3B '77-'80 350 557752


http://oldsjunction.classicoldsmobil...Unit%20Numbers


Allan