The YS 110 is in a different league
It runs as well as the YS120 we use in pattern 10 years ago. The thing has unbelievable power.
My old OS 91FS gets about 9K on a 14x6
In that particular case, It may be tough to cut down on prop diameter. It's a lot of engine, and as long as you are RPM limited (mechanical limit - just the nature of 4 strokes) it makes prop selection a bit tricky. But sincve you have all the HP in the first place, and you are pulling heavy pitch as it is..... Id imagine the 14/12 is about right for what you have there.