I used DuPont Variprime and Centari single stage black for my '31s engine. If I was to do it again, would use epoxy instead of the Variprime plus the single stage paint. Regardless of that, it is holding up well. Luckily I started with a factory fresh, new engine, but I still did a thorough cleaning, ground the flash, washed it with Tide, then again with wax and grease remover. That old saw that granny used to say - "Cleanliness is next to godliness" holds true here