3/25/2010
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Company: Diamond Pistons
www.diamondracing.net
Double-Coated Pistons
First Production Competition Pistons To Have Friction-Reducing, Heat-Resistant Coating Now Available
Diamond Pistons has introduced an ambitious new formula—a notable step forward in piston performance—the Diamond double-coat.
By combining hard-coat anodizing with a moly-skirt coating, Diamond’s double-coat pistons are particularly useful in power-adder applications.
The anodizing process provides a thermal barrier and increases both corrosion-resistance and wear-resistance. It also deters piston rings from micro welding themselves to the ring grooves and it creates an excellent adhesion surface. The baked-on molybdenum dry-film lubricant skirt coating provides an anti-friction anti-scuffing surface; hence this new combination resists high cylinder temperatures and pressures and frees-up a little more power.
To compensate for the additional build-up from the anodizing process, extra machining clearances are required, about .002˝ on the piston diameter and also on the width and depth of the ring grooves. Then the pistons are submerged in a detergent-acid bath, followed by two rinses before the anodizing process and three rinses after.
In the coating room, five light coats of the moly dry-film lubricant are applied to the pistons, which are then baked in an oven for an hour.
Diamond has been developing and testing its double-coat procedures for more than two years and conducts all of its coating processes in-house. The turn-around time for the Diamond double-coat process is about two days and the cost is $50 per piston. Single coatings, either anodizing or moly-skirt, are still available.
For more information visit www.DiamondRacing.net.