[Steve C.]

You can anodize an aluminum casting, but it's a challenging process. Not not all alloys are suitable, that and they are often porous.

[Steve C.]

I've seen some frown on high temperature ceramic coat on intake manifolds stating it holds in heat.
Personally we have experienced no issues with a bright ceramic coating finish on my intakes.

I've never used a satin finish as in the example in my post #2.
However as shown there I agree it's light grey appearance of natural aluminium has the potential to retain the new part look.

If one has a concern for holding in heat here is another potential option I found on the internet. Have it Vapor blasted.
The author states it anneals the pores in the aluminum and resists corrosion. The finish is smooth to the touch, not like sandblasting, and looks fantastic.
To clean he just sprays some WD40 on a rag (not a lot) and wipes it down when it is dirty.

Attached here is a part finished with this method:

https://cimg7.ibsrv.net/gimg/www.cor...03f0140c77.jpg



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