I went up an inch in pitch from the stock 9.9 prop but, I’m sure that will vary will the application. Here’s my notes from testing with a new bare bones Lowe 1448M:
Stock 9.9 prop.
9.25 x 9”: 4111-093-09A. 23mph at approximately 3/4 throttle 6350 rpm. Hitting rev limiter.
Solas Amita 3 props...