Most of the noise comes from the props being so close to the chassis, motors were raised on the P4 that cut noise and then they went for the low noise props. Any conversion out there would raise props and use the low noise props anyway so killing all the birds with one stone, not Drone, hopefully.I don’t know about a conversion kit for P4 props, but have you tried using Xoar beechwood props for P3P? They are the only props that I use. They are perfectly balanced and are considerably more quite than the stock props. On amazon they are $30.00-$40.00 a set, depending on the color you choose.