The low-down, if you are short on time:
Based upon independent testing of Mobil 1 Annual Protection Full Synthetic and AMSOIL Signature Series 5W-30 in the Kurt Orbahn test, AMSOIL Signature Series withstand extreme heat and shearing forces, exceeding industry standards and outperforming competing brands. In fact, AMSOIL fights viscosity breakdown 46 percent* better than Mobil 1. AMSOIL stands up to the devastating effects of high-horsepower, modern engines for maximum protection.
The longer version, if you ready want to understand the independent testing of AMSOIL vs. Mobil 1:
Most lists of top-10 performance modifications include a turbocharger, supercharger, nitrous oxide or updated engine tune. Increasing the engine’s oxygen intake also increases fuel, which boosts power. While all that extra power is great, it puts additional demands on your engine oil.
Your main bearings – and, for that matter, the time, money and effort invested in your vehicle – rely on an oil film that’s thinner than a sheet of paper. Adding horsepower increases rpm and engine stress, placing even more stress on the oil. Many enthusiasts make compensatory upgrades to the crank, pistons, cam, etc. to handle the additional pressure.
In this scenario, upgrading the engine oil is often overlooked. But it’s an important consideration since engine upgrades can increase shearing forces, which result in viscosity loss. And viscosity is the most important property of oil.
Shear results when one layer of fluid moves in a direction different from another layer of the same fluid.
Shear (often called mechanical shear) occurs when one layer of engine oil moves in the opposite direction of another layer of the same oil. A great example occurs between the piston and cylinder wall. These two oil films move in opposite directions under intense heat and pressure. Therefore high-horsepower, high-rpm engines create increased possibility for viscosity loss due to shear.
This scenario can shear, or tear apart, the molecules of viscosity-improver additives, which are used to extend the viscosity range of the base oil. The application and type of base oil determine the type of viscosity improver. Some viscosity improvers resist shear better than others. And some synthetic oils don’t need viscosity improvers at all due to their ability to withstand shear.
If the engine oil loses viscosity due to shear, it can fail to provide the required level of wear protection. Think of the force transferred through the piston, rod and crank to the thin oil film protecting the bearing. There’s not much room for error.
AMSOIL uses naturally shear-resistant base oils combined with top-tier, shear-stable viscosity improvers. AMSOIL synthetic engine oil withstands extreme heat and shearing forces, exceeding industry standards and outperforming competing brands. In fact, it fights viscosity breakdown 46 percent* better than Mobil 1. It stands up to the devastating effects of high-horsepower, modern engines for maximum protection.
*Based upon independent testing of Mobil 1 Annual Protection Full Synthetic and AMSOIL Signature Series 5W-30 in the Kurt Orbahn test, oils purchased on 05/03/18.