Michael,

I think they are a greenish grey. I have a 33 Hudson 8, and there were vestiges of that color left. I've seen some of the old Hudsons of this era with engines of that color as well. But exactly what the color is or where to find an appropriate engine enamel, I'm not sure. Many just painted them the silver/aluminum color for lack of info. I think the Packard engine color is more green than the Hudsons were, but hard to say without a clear example.

Tim,

Thank you. The lack of info is really surprising as the "New Greater 8" engine was such a big part of their marketing in this era, Yet I cannot find one period advertisement showing the engine or anything else that would make me feel comfortable about choosing one color over another. The Silver/Aluminum is by far the most common and if I cannot find any conclusive evidence I will most likely go with that. But, I would really like to know for sure.

MIke, I'm pretty sure it's a greenish gray. Perhaps these aren't the best pictures, but here's an 8 in that color, and the car is basically unrestored (1933 Hudson 8). I'm sure they used the same color on the 8's starting with the 1930 engines and through 1933. By 1934, they went to the silver/aluminum color, pretty sure.

Good advice from Tim. This subject has been debated several times in the last 40+ years. Consensus seems to be some where near an Avocado green mixed with light industrial gray. That is what was on my one owner 1932 Hudson when I bought it in 1966.
Color preserved in spots by the years of accumulated dirt/grease/leaking oil.

Fred "Ric"

Thank you all for the advice and pointers, we mixed up some paint and I think it turned out wonderfully. The car is being shown this weekend at The Elegance at Hershey Concours and it already shipped so I cannot share pictures today. But, I will as soon as it returns home.