I suppose this is the right place for such a question.... What is the highest detergent motor oil? Would it something like Rotella? I am finalizing a refresh of a nice "barn find". The engine hasn't been running in.... maybe 6 years. I want the first fill to be an oil that will clean things up as best as possible. And yes... the engine turns over and all ports appear to be clear and allow lubricant to flow. Once I fill the sump.... I am ready to fire her up.