RE: smaller prop than suggested?
Sorry, I thought you were talking about a 91 4-Stroke.
But even a 2-stroke is not going to get 16,000 RPM unless you are running it in a ducted fan jet - and then you can count on it lasting about a year before it burns itself up at that speed.
You should shoot to get 11,000 to 11,500 RPM out of it and prop accordingly.