Coating Exhaust Manifolds
Exhaust manifolds can either be a cast iron, factory-type manifold or a tube steel header typically used in performance applications, though they are becoming very common in OEM applications. There are a variety of reasons for coating an exhaust manifold header. #1 Corrosion protection. The manifold will live longer as well as look nicer. Whether it is for performance or show, coating an exhaust manifold is valuable to you. #2 the coating is a thermal barrier, thus keeping heat within the manifold or header. There are a number of benefits for this. First, by keeping heat within the manifold, you're going to accelerate the exhaust gas velocity which reduces back pressure and reduces fuel contamination due to reversion. This is a performance benefit. Second, you'll reduce the surface temperature of the manifold. This means if a person comes in contact with it, they are less likely to be burned and leave skin behind. If there is a component close to it, it will not see as much heat as it would with an uncoated manifold. In addition, not as much heat will be radiated under the hood or into the engine compartment. This reduces the underwood temperature which, again, reduces the temperature of surrounding parts, such as, alternators and starters. It also reduces the amount of heat that can be drawn in through the carburetor, which is a secondary performance benefit. There are a variety of coatings that can be used on exhaust manifolds or headers.
The most popular is our Cermakrome. This gives a near-chrome finish, tremendous corrosion protection and is an excellent thermal barrier. On the stock side, our Color-guard Cast Iron is extremely popular, especially with restorers, since it imparts an original, dark cast iron appearance rather than the lighter appearance that is more typical of a bead-blasted finish, which is not truly stock.
Color Schemes can play a large part in custom cars. We also supply a variety of other colors including aluminum, black, white, gray ice with new colors in the future. A clear coat can be applied to give pipes a glossy look.
For tube steel headers, the engine application may need added protection. 9 to 1 Comp. Engines naturally have a hotter exhaust.
A base coat of a thermal barrier and them Cermakrome or other colors will allow a high running temperature of the outer coating.
Chrome headers have a problem with turning brown, blue and purple. Note: (Thermal barriers are intended to reduce heat transfer by about 30% on the average. Chrome will start turning brown around 450 degrees, turn blue around 500 degrees and after that they just look nasty. Chrome looks good but is not durable.
A badly tuned engine can drive temperatures of your exhaust out of sight.1000-1500 degrees. (No coating on the planet will stop Chrome from bluing).
In cases were known temperatures will be very high. Contact JCM and we will assist you with your needs.