[bigblockv6]

You and your supplier can giggle all you want but both of you are not Dupont or PPG, there are legitimate reasons why these two exceptionally large corporations make formulas for engine colors in their automotive line of paints. In their research they expose painted steel panels and place them in the hot desert sun for months to test the durability of the product, So if it will hold up to that it will hold up to the heat of an engine. There are restoration websites that even recommend using these paints because many colors can't be bought on the shelf. Myself and a few engine builders that I know have been using these products. I've been doing it for 32 years and never had problems!