I have a 19 foot bowrider 1985 with a 3.0 stringer drive. The prop is a 3 1/4 x 17 pitch which runs at 39-4000 rpm wot trimed. I recently got the boat and have no idea what speed is normal for. Right now it runs about 23 on my gps, i think this is kinda slow but hopfuly someone will chime in...