Hi everyone. i have purchased this boat a few weeks ago and i am planning to modify it a bit to suit my needs. this is a river cruiser 9.5m long and…. How fast does it go? for estimating the speed for small outboard planing boats see planing speed boat chart. this chart should be used for. Proven boat designs, and how-to information for boat building. boat plans are for beginners and have been built by thousands since 1953..