I think you'll find the 14X8 to be a tad too much prop for that engine. That is the perfect prop for a 1.00 class engine. All of my .91 FS's run either 14X6 or 13X8. I've tried 14X8 on them before (because I also own a saito 100, so I have some 14X8's laying around). The .91's struggled a bit to achieve a good top end, and also ran very hot. But you can see if you get any different results..