I was under the impression he meant to make them behave better. I know there were modifications to some of the engines like the .40 and .50 to make them more tractable. There is a newer head button for the .40s that allows more nitro beyond the 5% maximum for many Fox engines. I also know the midrange was a bit lean in some of the .40s and there was a needle modification in the .50 among other things. There were other "projects" mentioned for other engines like the 1.20 twin as well. Of course I could be completely wrong which wouldn't surprise me.