Just my $.02, I was too cheap to spend $150 to have J&M speedcenter polish my SBC Vortec PerformerRPM intake, so I spent over $300 on sanding rolls, flapper wheels, etc. and after days of grinding on it, it still wasn't anywhere near shiny. Of course then Edeljunk came out with an AirGap RPM the very next month and I had to buy a new intake. This time I spent the $150, but the polished mowed all the detail off of the casting.
After polishing all my boat aluminium, I had Embee spray it with their clear ceramic coating. It has lasted without dulling and doesn't turn milky like clear powdercoat. Techline Coatings makes a clear to put over bare polished metal and I am sure that Kings offers a similar process. If you hate polishing as much as I do, look into a clear coat.
Another alternative would be zinc coating. Embee did a really killer black zinc coating on Larry Merisch's top alcohol dragster induction.
Cheers,
Joe
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