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The other area that could affect the performance of the VVT is shear stability. Viscosity is the most important property of a lubricant, and motor oils are required to work over a very wide range of temperatures – think starting a car in Minnesota in January and driving a car in Arizona in July. To improve the viscosity attributes of the oil, polymer additives called Viscosity Index Improvers are added to the motor oil. These Viscosity Index Improver polymers can be degraded under high shear conditions. Think about stretching a rubber band. Pull too hard and it breaks. This can happen in VVT engines as the oil is being forced through the narrow passages of the VVT under high hydraulic and mechanical load.
The shearing or breaking down of the Viscosity Index Improver polymer leads to lower oil pressure and degraded viscosity characteristics. Both of these conditions will affect the performance of the VVT system.
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The better the air release properties of the oil, the better performance you will see from the VVT. New mPAO base oil (available in all Driven lubricants) offers dramatically better air release properties than conventional synthetic base oils. In the ASTM D-892 foaming test, the mPAO demonstrated more than a ten-fold reduction in foaming tendency compared to equivalent viscosity products. Thus, choosing an mPAO-based product for your VVT engine means inherently lower foaming tendency.
Quote:
The other area that could affect the performance of the VVT is shear stability. Viscosity is the most important property of a lubricant, and motor oils are required to work over a very wide range of temperatures – think starting a car in Minnesota in January and driving a car in Arizona in July. To improve the viscosity attributes of the oil, polymer additives called Viscosity Index Improvers are added to the motor oil. These Viscosity Index Improver polymers can be degraded under high shear conditions. Think about stretching a rubber band. Pull too hard and it breaks. This can happen in VVT engines as the oil is being forced through the narrow passages of the VVT under high hydraulic and mechanical load.
The shearing or breaking down of the Viscosity Index Improver polymer leads to lower oil pressure and degraded viscosity characteristics. Both of these conditions will affect the performance of the VVT system.
Quote:
The better the air release properties of the oil, the better performance you will see from the VVT. New mPAO base oil (available in all Driven lubricants) offers dramatically better air release properties than conventional synthetic base oils. In the ASTM D-892 foaming test, the mPAO demonstrated more than a ten-fold reduction in foaming tendency compared to equivalent viscosity products. Thus, choosing an mPAO-based product for your VVT engine means inherently lower foaming tendency.
