I am considering running a 50/50 blend of Aeroshell 100W conventional oil and 15W-50 synthetic in an experimental turbocharged Lycoming IO-540. Yes I heard that pure synthetic was tried in 100 LL AVGAS engines and there was problems because the synthetic oil did not have detergent properties and it was not washing away the lead contaminants so running 100 percent synthetic is most likely not good. That is disappointing because the lubrication properties and warm oil viscosity of synthetic oil is superior to the conventional mineral oil...so what does the collective think about a 50/50 blend??? Would it not be able to achieve the best of both products meaning the cleaning properties of the dispersant aviation oil and the better lubrication of the synthetic? Has there been any studies on this thought with respect to AVGAS 100 LL engines? Any thoughts would be greatly appreciated!!!