Mobil releases an update occasionally. Below is the most recent. Notice there are 5 pages; notice that the Phosphorus & Zinc levels vary as well as viscosity. DO NOT be seduced by the ‘more is better’ cliche’. If you have an older solid lifter engine (like a 356) the best bet is the 15W-50 on page 3. Don’t use the Motorcycle or Racing formulations on page 5 even though they have more Zn & P. They are likely lacking in other additives that are common in over the road oils… like water trapping and de-emulsifiers… since the premise is that the oil is changed out after every race. Also the Diesel engine formulations have different levels and types of detergents to cope with fine particulate soot. These can have unintended consequenses in a gasoline engine.

One more thing before we get to the listing. Here is a link to a simple explanation of the viscosity grade nomenclature. https://www.mobil.com/en/lubricants/for-personal-vehicles/auto-care/all-about-oil/ask-our-auto-experts/explaining-viscosity-designations