[Adger Smith]

Greg
I have been doing engines since I was in High School back in the mid 60's. I have seen head cores that are all over the place with numbers.
I have seen cores that came from 2 different core box sections. Like down in the water passage there is a 487 cast in the bottom mold and then a 992 up on the top with the shift and mold and date codes. To me that just tells me that the foundry put two core boxes together to keep production up. You know they do anything to keep production going. Every one I have seen with a 487 in the water passage had a large volume intake runner. Like they used the bottom half of the core as a 487X and the top with another number on it.
I'm pretty sure there were some old guys back then that were savvy to anomalies like this and ran faster than those of us that had not figured it out.
OK, Billy and Dwight run with it..