It's simple. The engineering, add packs, and chemical makeups of 20wt oils are stronger than you're willing to believe. You also seem to forget there are multitudes of ways to control and remove heat from an engine.... Pro Stock engines run 0W5 oil, and turn 10k+ rpm and make nearly 7 times the power of the Subaru. Here's some science for you:lul is that all you wanted to say? Where is all this factual information you are getting this from? Come back when you can explain why Subaru suddenly decided to change to a 20wt in a hotter performing engine outside of quoting cafe standards.
Hence, with upgrades to 20wts thru things like dexos1 Gen 2 requirements, along with other strict tests for durability, it's certainly possible to run a thinner oil, especially when you've got engine dynos and testing methods to verify results.Driven Racing Oils said:Next generation mPAO synthetic base oils deliver a viscosity index approaching 200, and that is a game changer. Using an mPAO based oil, you can now safely run 1 viscosity grade lower that you would using a conventional based mineral oil. If you are running a conventional 20W-50, just by changing to an mPAO based 10W-40, you can reduce start-up wear without sacrificing high temperature durability or oil pressure. Driven Racing Oils