John Hutchins who made hull says he thinks I can get another knot maybe two with a good 3 blade nibral. I have a four blade bronze - I cruise at 19.5-20.5 knots at 2125 RPMS at 14 gallon per hour with a Volvo 500. Max RPM is 2600 RPMs. The boat is impressive just tweaking it now - I have no vibration with a four blade, hoping 3 blade will run smooth enough. I want speed - what do you think?