Originally Posted by sherwood

Use what your car calls for, there will be little to nothing to gain from going any higher. Some cars can make up for it with modifying timing, but usually it's all malarkey.

Now I do respect your butt dyno testing, but overall there are many other things to consider such as ambient air temp, engine temperature, relative humidity and many other things. Basically don't waste your money, just follow the directions on the gas cap.