Since the upgrade, I see a 57% increase in speed, a 27% reduction in fuel burn, 30 degree reduction in CHT's, and the engines are much happier in all of the RV's!!!!!
I spent about half my youth at the Omahawks R/C flying field, wiping castor oil off of wings and fuselages. I hardly knew what a sandwich tasted like without castor oil. When they started using the red synthetic stuff, it was just horrible.