Boat Speed and Prop Slip calculators

DaleH

Well-known member
TinBoats Supporter
Joined
Dec 12, 2014
Messages
3,352
Reaction score
73
Location
Eastern Mass
Here are a boat speed and prop slip calculator if anyone is interested:

Theoretical Hull Speed = ( Prop Pitch X RPM ) / ( LU Gear Ratio X Constant of 1056 )

Prop Slip = ( Theo. Speed - Actual Speed ) / ( Theo. Speed )

I have found the speed one pretty accurate with small open v-hull skiffs. But where a lot of your guys' boats have extensive flooring, decking, and compartments ... I'd expect lower actual speeds due to the actual weight carried. Also note a jon boat will have more wetted surface on the running hull and will be slower.
 

flex

Well-known member
Joined
Feb 8, 2017
Messages
59
Reaction score
0
Thanks man. I'll try and figure it out. Going to raise the motor up a bit and play with trim this weekend. I just figure I had a fiberglass glasstream bass boat years ago with a 70 that ran 42. This boat weighs half as much it should scoot! Hopefully I can get it dialed. I'll post up as I experiment. Hopefully put a tach on soon as well.

Sent from my HTC One M9 using Tapatalk
 

Stumpalump

Well-known member
Joined
Dec 2, 2013
Messages
811
Reaction score
0
Good calculator here:

https://www.mercuryracing.com/prop-slip-calculator/
 
Top