I thought it would help with the high exhaust temps more than intake, also the cost vs. result would kind of make it pointless. It would look awesome though :drool:
I think it might have some merits in some systems, but a thermal spacer is better use of $ IMO, on saying that bear in mind that there is 2 gaskets that need to seal with a spacer adding to things that could go wrong.
There is a lot of anecdotal evidence regarding ceramic coatings reducing under bonnet temps and holding heat in with
ex. mani., it does work in high heat applications, but as to the
real figures I think it would be dependent on too
many variables. Ceramic coating spreads and evens the heat out across the surface it's attached to, that's why it's great for piston crowns with oil squirter delete.
I think there would be better places to spend money rather than getting proffesional coating the intake tract, however if you wanted to experiment maybe this stuff might do the trick as well as customise your engine bay, my 2c ↓
https://www.duplicolor.com/products/enginePaint/