Hey Bob

If the ambient temperature is in the 70's to 80's and you run the engine lean with say CP30% LS[20% oil or fuel with less oil], there will be a minimal smoke trail. The problem is as ambient temperature goes up pump life goes down dramatically! In my opinion it is going to take a completely different pump design to allow the pump to "live" in all temperature ranges we fly in! I could be wrong, but the 'fixes" being discussed seem to be "band aids" but it may be all it takes! Time & testing will tell.

Dick