Originally posted by jettstarblue:
Yes, actually I buy 15%, and then ad a few oz. of castor. I run this mix in ALL my engines, 2 stroke, 4 stroke, bushed, and ball raced.
There you go. Most people don't add anything to their fuel. I think we have gotten a little side tracked from the original post. Which brings me back to the question of why RJV needs 15% for a bushed .40? 10% was working fine and he did not mention any performance issues. 10% is also easier on his wallet, so why change?