The tin covers are semi gloss black the aluminum ones are left bare The manifolds new were a silvery gray cast iron color but quickly changed to the brown rusty look of cast iron in the open I have been powder coating the tin ones with the semi gloss and using a gray hi heat manifold paint from POR 15 It is a bit darker than what the cast iron looked new but is quite close, I also do the aluminum covers in that as well I have tried numerous coatings on manifolds and/or headers over the years and nothing really stays on but this stuff stays the longest and still looks pretty good
Thanks, Rick