The biggest achievement with the new Ultra line is Holley’s foray into the aluminum body market while previous generations were made from zinc. Zinc itself is a bright silver-like metal, and the problem with untreated zinc is that it reacts with air and water to make a powdery material known as ‘white rust’. The green of the typical Holley carburetor actually comes form a chromic acid solution, which forms a thin layer on the surface of the metal and helps protect the surface.

Posted by Mark Gearhart