Engine color 1969 Swinger 340

I can see the Turquoise looking more Blue with age.
Anyone know the process for engine paint colors being choosen by the maunufactures?
There has to be a reason for a given particulate color choosen.
What is it?

All color choices were made by the exec's wives. ;)

Besides the great turquoise vs blue debate also keep in mind that not all the assembly plants were in synch when it came to switching engine colors from one model year to another. Depending where/when your car was built may be a factor why your engine is a different color from what the books and the "experts" say it should be. This was based off of a conversation I had many years ago with a Hamtramck line painter.