Hypereutectic pistons are cast internal combustion engine pistons made from aluminum with over 16% silicon content for strength and durability. The term 'hypereutectic' comes from eutectic. Special melting processes are necessary to ‘supersaturate’ the aluminum with additional silicon content. Special molds, casting and cooling techniques are required to obtain finely and uniformly dispersed silicon particles throughout the material. This produces pistons that are very hard, thus brittle. They have proven to be un-forgiving with engine knocking. For this reason they are great in naturally-aspirated engines, but should be used with caution for 'nitrous', super- or turbochargers. Generally speaking, forged pistons are a better choice for high boost. One half of a bronze mold for casting a socketed spear head dated to the period 1400-1000 BC. This article is about the manufacturing process; for other uses, see Casting (disambiguation). ... piston + connecting rod In general, a piston is a sliding plug that fits closely inside the bore of a cylinder. ... Aluminum is a soft and lightweight metal with a dull silvery appearance, due to a thin layer of oxidation that forms quickly when it is exposed to air. ... General Name, Symbol, Number silicon, Si, 14 Chemical series metalloids Group, Period, Block 14, 3, p Appearance dark gray, bluish tinge Atomic mass 28. ... A eutectic or eutectic mixture is a mixture of two or more elements which has a lower melting point than any of its constituents. ... In physics, melting is the process of heating a solid substance to a point (called the melting point) where it turns liquid. ... HI JAMIE!!!!! In chemistry, the term supersaturation or oversaturation refers to a solution that contains more of the dissolved material than could be dissolved by the solvent under normal circumstances. ... It has been suggested that Detonation internal combustion engine be merged into this article or section. ... A naturally-aspirated engine (NA - aspiration meaning breathing) refers to an internal combustion engine (normally petrol or diesel powered) that is neither turbocharged nor supercharged. ... A Nissan 240SX equipped with nitrous oxide injection purges the nitrous oxide supply line before making a dragstrip pass Nitrous is a slang term for nitrous oxide (N2O), commonly used by drag racing classes like Pro Street, Top Sportsman, and Pro Mod. ... A supercharger (also known as a blower) is an air compressor used to compress air into the cylinders of an internal combustion engine. ... Air foil bearing-supported turbocharger cutaway made by Mohawk Innovative Technology Inc. ... A blacksmiths forge The forge or smithy is the workplace of a smith or a blacksmith. ... A Boost in automotive engineering is a positive manifold pressure in cars with turbochargers or superchargers. ...

Hypereutectic pistons are used in many original equipment engines. They are favored because of reduced scuffing, improved power, fuel economy and emissions. The reduced thermal expansion rate allows the piston to be run with reduced clearance, which reduces losses due to gases escaping past the sealing rings. Fuel efficiency, sometimes also referred to as fuel economy and commonly gas mileage in the United States, is a numeric measure often used to describe the amount of fuel consumed with regard to the distance travelled in a transportation vehicle, such as an automobile. ... The word emission generally means sending something out. ... In physics, thermal expansion is the tendency of matter to increase in volume or pressure when heated. ...

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