i agree w/ bucket's mach shop guy... 100%
Use an additive like lucas or comp cam and straight 30 wt on breakin first 500 miles.
everything you did want to know but don't have time to read:: I go read stuff alot................. some great points if you follow the notes or link to the many web sites offering info on additives.
Zinc
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Background
Zinc is an elemental metal. It is listed on the Periodic Table as "Zn," with an atomic number of 30 and an atomic weight of 65.37, and it melts at 788°F (420°C). Zinc is usually a gray metallic color, but it can be polished to a shiny silver luster. In nature, it is only found as a chemical compound, not as pure zinc, and can be used as a raw material for castings and coatings.
During the era of the Roman Empire, people used zinc to alloy copper into brass for weapons. In this crude process, the zinc was captured by the copper during the heating of the ores, though little was realized at the time about the importance of zinc in metallurgy. The name zinc may be derived from the German word "zinn," which means tin. The scientific discovery of zinc is credited to Nadreas Sigismund Marggraf, a German chemist who isolated pure zinc in 1746. The first production facility, or smelter, was founded in Bristol, England by William Champion shortly thereafter.
Only about 5% of the world's zinc supply is mined in the United States, with the balance coming primarily from India, Mexico, and Canada. Approximately 6.7 million metric tons of zinc ore are produced worldwide. Roughly two thirds of the zinc used in the United States is imported.
Applications
Zinc is primarily used for galvanizing steel against corrosion, die casting of intricate machine parts, and in batteries and other electrical applications. Zinc is also alloyed with copper to form brass.
Galvanizing steel involves applying a thin coating of zinc to all exposed surfaces of the steel to guard against corrosion. Zinc offers excellent corrosion resistance because it is more easily oxidized by the atmosphere. Oxidation occurs when metal is exposed to air or water, and electrons from the metal transfer to the oxygen. When zinc is tightly bonded to steel, the zinc frees up its electrons more readily than the steel, leaving the stronger metal beneath intact. The application of the zinc coating is accomplished by dipping the steel into molten zinc or by electrolytic plating of the steel with zinc, much like chrome plating.Die-casting alloys typically contain 96% zinc and 4% aluminum. The die-casting process uses a two-piece steel die and a casting press to hold the die halves together during injection of the molten metal. Inside the steel die is a cavity that has the negative image of the part to be cast. The molten metal is injected into the cavity under pressure, accurately filling the entire void. The metal cools, and the press opens the die halves, revealing the formed part. The zinc cast parts are very close to the desired shape, requiring little machining before they are placed into an assembly. Typical applications include copier, aircraft, and medical instrument parts. Automobile makers use zinc die castings for emblems, moldings, door handles, and brackets. Zinc die castings are easily chrome plated for durability and appearance.
One unique application of zinc takes particular advantage of its ability to transfer its corrosion resistance properties by electrical contact. This application is called a "sacrificial anode." The anodes, made of almost pure zinc, are bolted to aluminum marine engines. During operation in water, especially salt water, the oxidation forms a weak electrical current, which may corrode the hull and engine parts. Since zinc is easily oxidized in the presence of this electrical current, it "sacrifices" itself by corroding quickly, consuming all of the electrical imbalance in the ship. The remaining aluminum hull and engine are not corroded as a result. As it is consumed, the anode must be replaced to assure continued protection.
In an application similar to the sacrificial anode, zinc is used as a component in battery production. The dry cell battery creates a chemical reaction with zinc in a metal housing (or "can") that results in a voltage potential between two connections. An electrical device, such as a flashlight or portable radio, can be connected to the battery and powered by the electricity produced. Thus connected, the reaction maintains the electrical current for the duration of the available chemical reactants.
Zinc as a compound is used in pharmaceuticals, rubber, cosmetics, paint, and ceramic glaze. Other compounds use zinc in cathode-ray tubes, soldering flux, and wood preservatives.
http://findarticles.com/p/articles/mi_qa5481/is_200604/ai_n21390204 INTRODUCTION
The efficiency of automotive engines greatly depends upon several metallic components, such as tappets (followers) and camshafts used to transmit power by sliding and/or rolling under high contact loads and elevated temperatures. In the absence of effective lubrication, these moving parts are prone to high friction and excessive wear, potentially leading to reduced fuel efficiency and short life. Mechanical energy losses in internal combustion engines typically account for 10-15% of the overall power losses due to friction in the pistons, piston rings, main bearings, connecting rod bearings, and valve trains (Kiovsky, et al. (1)). To overcome these drawbacks, interacting metal surfaces must be lubricated with properly selected oils fortified with special additives that reduce wear, corrosion, and oxidation, while providing high load-carrying capacity and low friction.
An important property of engine oils used to enhance the friction and wear characteristics is the ability to form tenacious antiwear tribofilms strongly attached to the metal surfaces.I A thin oil film of thickness less than 10% of the peak-to-valley surface roughness can separate the surfaces by a continuous film provided the local shear stress does not exceed the shear strength of the lubricant (Jacobson (2)). However, in the boundary lubrication regime, an oil film generally cannot provide full coverage of the sliding surfaces (Martin, et al. (3)). This suggests that the shear strength of the oil film is exceeded by the shear stress produced at asperity contacts. Hence, it is difficult to maintain a continuous and uniform oil film thickness at boundary-lubricated sliding interfaces. For effective lubrication, it is essential that asperity contacts behave like small slider-bearings lubricated with a high-pressure glassy lubricant and also as plastically deforming solid films so that they can be uniformly smeared across the contact interface (Jacobson (2)). It has been theorized that the minimum pressure for plastic flow to occur increases with lubricant-surface reactivity and adsorption heat (Zhang, et al. (4)).
The in situ formation and adherence of tribofilms on rubbing metal surfaces have been found to strongly depend on temperature, additive(s) type, and additive concentration in the base oil (Kim, et al. (5)). Tribofilms strongly attached to the sliding surfaces increase the wear resistance by playing a sacrificial role, thereby protecting the metal surfaces from high shear rates. The metal surfaces can be protected provided the degrading tribofilms can be replenished in situ through rapid reaction with the freshly exposed metal surfaces. Tenacious glassy tribofilms, such as phosphorusand/or boron-containing tribofilms, are potential antiwear agents (Komvopoulos, et al. (6), (7)). However, this beneficial effect is usually accomplished at the expense of higher friction. It has been reported that the lower shear strength of sulfur-containing tribofilms compared to phosphorus-containing tribofilms is the reason for the lower coefficient of friction and higher wear rates obtained with these tribofilms (Komvopoulos, et al. (7)).
Molybdenum-containing compounds have been proven effective friction modifier additives for engine oils. The in situ formation of molybdenum disulfide (MoS2) through complex tribochemical reactions has been known to reduce friction (Grossiord, et al. (8)). The excellent lubricating efficacy of MoS2 is attributed to its laminar crystal structure (Clauss (9)). The strong covalent bonding between Mo and S atoms in the hexagonal crystal provides penetration resistance when the load is applied normal to the crystalline lamellae, whereas the weak van der Waals forces between adjacent planes of S atoms enable sliding under a low shear stress (i.e., low friction). To perform well as friction modifiers, Mo-containing compounds must be used at relatively high concentrations and elevated temperatures (Graham, et al. (10)). The formation of MoS^sub 2^ is promoted under pure sliding conditions rather than sliding/rolling conditions (Graham, et al. (10)). The capacity of Mocontaining additives to produce low-friction conditions depends on the formation of MoS^sub 2^ at asperity contacts (Grossiord, et al. (8); Graham, et al. (10)).
