yes it's ceramic paint, the scale gear has the air lines right up next to the turbine and without the paint they get soft from the heat. soft airlines + 120 psi = no gear function

on the bell mouth i did use the original but my pipe started rippling after just a few runs and i replaced it with a Tam pipe.

Craig, if you don't have the shims installed your pipe isn't in line with the turbine. if by chance you were able to get it in line then you have a negative incidence of thrust built into the pipe (will climb at higher thrust settings)