Prop for O.S. 91 Fx
Please do not buy a dyna thrust for a 91fx. I bought one and the first time I throttled up it snapped at the root and tore the firewall out of my cap. I would suggest a MA 15x6 or better yet a bolly clubman 14.5 x 6 or 8
I used a MA 14 x8 scimitar for a while on mine and liked it. If you ever get over to evansville IN send me a note and Ill give you a used MA NY/fiber scimitar to try (14 x 8)