Ceramic coatings are another ways to squeeze out a few more horsepower from your ride. Ceramic coatings are typically used on exhaust components to reduce temperatures. However, their use is not limited to exhaust systems altogether. Ceramic coatings have a very low heat transfer coefficient. This means they do not absorb heat efficiently which makes them an excellent thermal barrier. This is why headers are commonly coated with ceramic paint to keep under hood temperatures low. A byproduct of retaining the heat within the exhaust gas instead of transferring it through the piping of the vehicle is also an increase in power. This occurs because the exhaust gases stay hotter longer which allows them to leave the vehicle at higher velocities. This means a reduction in backpressure and an increase in horsepower will result.
Ceramic coatings are most popular on headers, and less so on complete exhaust system piping due to additional cost and availability. Although coating both your headers and all the mandrel bent exhaust piping of the rest of your exhaust system would provide the best increase in horsepower. Header ceramic coating is usually available as an option for a few hundred additional dollars when purchasing headers. The coatings themselves are usually very thin on the order of less than a thousandth of an inch. However this is enough to provide a good thermal barrier within the piping allowing exhaust gases to escape the system much more efficiently. Horsepower gains of up to 3% have been claimed by coating an entire exhaust system. In a 300 horsepower vehicle this would equate to roughly 9 hp gained. It is evident that this modification can be a bit costly for the power it returns however it does have additional advantages as well. Ceramic exhaust coatings can reduce under hood temperatures by several tens of degrees Fahrenheit as well. This will keep your engine bay cooler and safer because the excess heat will not affect the fuel lines within the engine bay as much.
Ceramic engine coatings are a lesser known and used option to the general public. However the technology is available to coat many parts of the internal combustion engine with ceramics to reduce wear, decrease friction, and lower operating temperatures. Typically piston tops and rings are ceramic coated as well as valves, rods, etc. Coating the piston top with ceramics provides a fantastic thermal benefit. It prevents the extremely hot combustion gases from soaking into the piston material during the explosion within the cylinder. This keeps more heat and energy within the explosion itself which provides more horsepower and torque.
Any surface within the motor that is in contact with another surface while the engine is running will gain an additional benefit with ceramic coatings. An example would include the piston ring to cylinder interface. A reduction in friction will occur that will increase horsepower by allowing the moving components to operate more freely. Depending on how many internal engine components are coated horsepower gains can be anywhere as low as a few horsepower to 30+ horsepower.
The advantages to ceramic coatings are many, including a reduction in friction, reduction of under hood temperatures, and increased component life. However, ceramic coating can be a costly process and usually is not budgeted into many modification projects for that very reason. However with more advanced application processes being developed every year, the prices are coming down and perhaps someday ceramic coating will become an integral step in the production of many engine components.