of how well the oil is doing in the engine. 2 UOA's with at least 3 intervals of the same oil to get a good *accurate* reading is my plan. I'm on my 2nd run of Redline 5W30 and on the next OCI, I will do a UOA off this batch and then change again with Redline 5W30. By then, my batch of Redline will be depleted and then I will try Amsoil, GC, etc. What methods do you guys use if you want to determine which OIL works best in your engine.