Streets, how did you find that number??? We know for fact it is a GM/Chevy motor. Three different people have read the GM12486570 clear as day, so we're sure it's the right number, located exactly where everyone says it is, driver's side on block toward back of engine up top. Crystal Clear.

Some conflicting stories I've read says it is the famous Chevy 350 small block engine. The 570 at the end represents the 5.70 litre engine or 350 cu. in. The next two from 570 towards left I've read could be the year. In my case, it's 86, so I would have a 1986 Chevy 350 small block engine. That's great if it is, but I'm not sure, these are speculative stories about serial numbers; I wanted other opinions per say.

What does the GM12486570 casting number tell me the type of engine I have? Any aces out there on defining casting numbers? I'm a little hesitant to imaguine it's a 361 Henway, but it could be???