Can you explain that further LV
Are you saying that wrapping a non coated header is a no no?
YES !!!
Critterman:
The fact you have coated in the inside on a non turbo application is the way to do it.
Also this in some of my other posts.
PLEASE read the documents otherwise your statements have no support.
One quick point NA engines exhaust manifolds are never going to see the temperatures seen on OEM TURBO DI manifold engines.
It does not matter how many Honda/Toyota/Subaru you have done in the past, if the original OEM engine was NA.
Even if the engine was OEM turbo but not DI then that is also a different set of parameters.
Also a turbo housing is made of CAST and it has no bearing on this discussion.
The ONLY way this is going to go any where is with REAL life EGT figures, otherwise is just talk.
One last thing to chew on. The coating agents usually can withstand temperatures from 2000F to 3000F.
You could have a manifold with surface cracks and will not know it, because the coating agent will mask it.