'Sorry to drag this discussion over into the Model T world, but there has been an on-going controversy for years whether the Model T engine was painted black on the assembly line, left unpainted, or what. Good arguments for both. Most people agree that '26-27 engines were painted Ford Engine Green or some kind of green, which continued into the Model A era. But what about the so-called "black era" Model T's (non-brass),1917-1925? A lot of T guys paint their engines black, but others who want the cast iron look of an unpainted engine do what you have done with Cast Blast gray paint. I do that, too.
Attached are a couple views of a 1914 engine I redid for a friend in 2012.
Marshall