What fuel
Can you get the Morgan Omega 15%? Omega is pink and has some castor oil along with primarily synthetic oil. Coolpower is all synthetic, and I believe its oil content is lower than the recommended level for Q-40 and Q-500 engines.
The PowerMaster 15% is the provided fuel at all of the JR Gold Cup Q-40 races, and it is also the fuel used at our National Competition (for pylon anyway). It is a castor / synthetic blend.
In the Morgan line, the Omega is closest to the PowerMaster in terms of lubrication.
If Coolpower is all that is available, you may want to add some high quality castor oil to it. Let us know if the Omega is available.
To my knowledge, most people don't mix their own these days. The fuel manufacturers have figured out the right way to do rust inhibitors, oxidizers, etc.