This is another interesting topic.
Paints or maybe better put "coatings" come in a variety of different types. There's heat dissipating paints which have the ability to transfer heat rapidly and there are also heat insulating paints or coatings which minimize the transfer of heat. I remember a few years back when I had decided to strip and recoat the intake runners and plenums on my Porsche928, I removed all of the parts and started mediablasting in my blasting cabinet. The topcoat came of in seconds, but the lower coating primer or what?? wouldn't lift at all. Wondering what this stuff was, I turned to a forum dedicated to the 928. What I learned was the primer was infused with titanium oxide to insulate the intake runners and plenums from the surrounding heat dissipating from the engine. Crappers, don't want to remove this stuff. End result was I left the insulating coating and applied a heat resisant topcoat to "pretty them up"
If your serious about refinishing parts and you know what your end result goal is then your really looking for a "system" for your refinishing. I like working with
www.eastwood.com . They specialize in "Systems" and when your not quite sure of what you need, they have an engineering department which will answer emails and advise you with your next project.
Most people who dabble in performance engines are familar with ceramic coatings for headers like Jet Hot Performance Coatings
www.jet-hot.com/ This is a thermally insulating coating which keeps the heat in the part being coated. When Jet Hot is applied to headers, the heat stays in the exhaust gasses until exiting the exhaust system thus keeping the heat out of the engine compartment. Jet Hot also has a process for coating the piston crowns to keep the heat in the combustion gasses and reduce the transfer of heat to the piston tops. It can also be applied to the engine valve faces and combustion chamber roof to do the same thing. It's not cheap but if you're building really expensive race engines, you will spend the money on products like this.
Eastwood has a product which I have bought but not yet applied and tested. It's an internal coating for header pipes to keep the heat in the headers. The advantage here would be not allowing the headers to dissipate heat in front of the engine. Best part, it comes in an aerosol and it's a DIY product. At $24.95 a can, it's also cheap compared to Jet-Hot at $600 for a set of headers to be coated. It will be an interesting test although I plan to coat a set of new DG pipes so I won't have any initial heat temp readings from a set of DG's before coating.
If your interested in this product check out
www.eastwood.com/eastwood-hi-temp-intern...oating-w-nozzle.html