How coatings work to increase horsepower. Though there are a great number of ways that they function, for the sake of simplicity we’ll deal with the four basic ways that coatings help:

1.   direct heat to where it is needed
2.    reduce friction
3.    keep heat from where you don’t want it
4.    Improve heat radiation

If that sounds like a tall order for one coating, you’re exactly right. No single coating can do all of the above. Swain Tech has formulated specific coatings for each problem and environment. Simply, if you can control the heat energy, you make more power. Coatings help keep the heat in the combustion chamber and out of the piston, pin, rods and oil. Experts who use coatings in their race engines tell us that the typical results from one with thermal barrier coatings include an increase in fuel mileage, better throttle response due to a hotter combustion chamber, and an immediate difference in oil temperature, with the rod and wrist pin running cooler. Anti-friction coatings on piston skirts, valve springs and valve stems reduce scuff and frictional losses. Oil burn on the back of a piston becomes nonexistent.

Pistons

Here is where the highest power gains are realized. Pistons are made from aluminum. Aluminum gets soft under high temp (1400-1500 degrees F). Swain typically coats the top of the piston, the combustion chamber and exhaust ports with a ceramic thermal barrier coating called TBC™. TBC holds more heat in the combustion chamber rather than letting it dissipate through the piston, valves and head—where it is absorbed by the cooling systems. This, in turn, increases cylinder pressure that pushes down on the piston harder and results in an increase in power. Now in its fifth generation, TBC incorporates its exclusive Smart Coat process that bonds the coating to the base metal and expands at the same rate as the piston. Engines that use nitrous oxide, high boost turbochargers, superchargers and even nitromethane are prime candidates for Gold Coat, a heightened ceramic barrier that deals with heat spike and high-temp oxidation associated with these engines.

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The standard piston skirt coating is Poly Moly™, a ceramic medium with an extremely low coefficient of friction that reduces scuffing caused by the natural movement of the piston. Pistons that have short skirts and are subject to a high-revving, high-side-load environment are treated with PC-9™ (also reduces piston-to-wall clearance so that the piston maintains a straighter attitude in the bore and affects more positive ring seal).

Cylinder Heads

The engine creates 1400 degrees F combustion heat to make energy. The coating’s job is to insulate the cylinder head from exhaust heat getting into the water jacket. By insulating the combustion process, the engine achieves higher output but with less stress on its components. Swain applies TBC to the combustion chambers to improve combustion temperatures while simultaneously reducing the temperature of the entire casting. Swain routinely treats the exhaust ports as well as the faces of the valves. Peculiar to an aluminum casting, the exhaust port tends to heat up the entire cooling system because there is so much of it, and once the valves get up to operating temp, it’s difficult to cool them down. Swain’s TBC coating insulates the valve face and backside and keeps the air/fuel charge denser and cooler. Depending on rules or in an extreme case, this would equate to being able to use a smaller radiator and reduce frontal area of the car to improve aerodynamics.