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Performance & Hotrod Business - December '14

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70 n Performance & Hotrod Business n December 2014 HOTROD application. Some detergents (like those in API SN oil) are calcium-based and are much stronger than traditional sodium or magnesium-based detergents. They are almost twice as efficient at protecting the metals from dirt (and zinc). Oh, did I mention that SN detergents have about three times the "parts per mil- lion" count as the (EPA limited) zinc in the oil? I am sorry if you believe your brand still has the same specifications as it "always" had. Most of those telling us that they have not changed anything and have had no trouble go on to admit they only drive 1,000 or fewer miles a year. Their awakening will come later. Balance Each oil formula must have the proper balance of zinc versus detergents for the desired application. Each must have the proper balance of zinc/detergent types for the application. If you have a modern, catalytic con- verter engine you need a specific oil for that. If you are trying to establish the zinc boundary film in a new engine, you must have several times as much slow-burn ZDDP as you have detergent. For break-in, regardless of the quantities, the detergent in the oil must not be stronger than the ZDDP formula used. Some detergents are so strong (as in API rated SN oils) that no amount of ZDDP additive will work for break-in. You could put six gallons of ZDDP in these oils and still have the probability of camshaft lobe failure at start-up or in the first thousand miles. On the other extreme, a large amount of some ZDDPs will foul your cata- lytic converter. In fact, API SN oils have "Phosphorous Retention ZDDP" to mini- mize this fouling. (I told you there were many different ZDDPs. This is just another example of a different zinc formula.) Since 2004, the Environmental Protection Agency has mandated that no oil with a viscosity of 10W-30 or less can have more than 800-parts-per-million of any formula ZDDP (these oils are API rated SM or SN). The oil companies have been unable to meet this regulation with oil that is also suitable for older, flat tappet engines. It is probably not possible. If you have an older engine you need a specific oil for that. Oils have become very application-specific. When choosing an oil for your old car, choose one that has the right formula for an old car—not what is available at the auto parts store or big retailer. If the car is stored more than two weeks at a time, you can ensure longer life with an oil that has storage protection. Storage Protection If the engine is idle for any length of time, consider using oil containing storage protection. With this additive an engine does not get the surface rust or corrosion from the moisture that condenses when the warm engine is shut off. There is no need to periodically start the engine during storage. In fact, that just adds more moisture, rust and corrosion. Oil with storage protection has no secret magic ingredient and the technology is not new. It was developed for the U.S. Army in World War II. Most oils do not have it; I suggest looking for one that does. "Zinc" Anti-Wear film Metal Surface How Zinc (ZDDP) Works HEAT & LOAD Metal Surface Hydrodynamic Oil Film Full Film Lubrication As relative motion between the surfaces increases, the oil creates a "Hydrodynamic Wedge" that separates the surfaces. This low friction, low wear condition is called "Full Film Lubrication". Motion Motion Metal Surface Mixed Film Condition Mixed Film Lubrication As load increases, the "Hydrodynamic Wedge" that separates the surfaces begins to thin. As the opposing peaks begin to make contact, friction increases. HIGHER LOAD Motion Motion Metal Surface Boundary Film Condition Boundary Film Lubrication Under very high loads, the "Hydrodynamic Wedge" is broken, and the additive "Boundary" lm is what prevents direct metal-on-metal contact. Zinc (ZDDP) provides the "Boundary" lm to prevent excessive wear. VERY HIGH LOAD Motion Motion Metal Surface Boundary Film Condition Boundary Film Lubrication Under very high loads, the "Hydrodynamic Wedge" is broken, and the additive "Boundary" lm is what prevents direct metal-on-metal contact. Zinc (ZDDP) provides the "Boundary" lm to prevent excessive wear. VERY HIGH LOAD Motion Motion Metal Surface Mixed Film Condition Mixed Film Lubrication As load increases, the "Hydrodynamic Wedge" that separates the surfaces begins to thin. As the opposing peaks begin to make contact, friction increases. HIGHER LOAD Motion Motion (Images courtesy Driven Racing Oil)

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