I think they were just bare aluminum. As for restoring these pieces I painted my valve covers and throttle body using aluminum colored spray paint. It was brighter in color compared to the original look but I liked it better. If your looking for an exact color match or very close to it I've seen spray paint at pep boys that said cast aluminum on it and they even had it in two different shades, light and dark. This might be a little more appropriate. Although the intake might need high heat paint. I used a spray paint that said engine enamel on it. Resists heat up to 500 degrees. Of course unlike the valve covers and throttle body I didn't want to take off my intake so I just sprayed some in a cup, dipped cotton swabs into it and then just carefully brushed the areas of the intake manifold that were visible. you have to have patience when doing this, doing a small area at a time, and you might want to wrap your injectors with masking tape really quick so you don't get paint on them. Thats the easiest way I could think of to restore these pieces. Just test the color first on something else to make sure thats what you want. just to give you an idea of what I did, hope this helps.