A 40FP with the stock muffler will hover a 3 1/2 pound plane, but just barely. Replacing the stock muffler with a mousse can muffler will boost the power to hover a 4 pound plane, but again just barely.

The Mojo 40 usually comes out around 4 to 4 1/2 pounds, so the 40FP would not be a good match.