What is

[Tony M]

The Correct Way to figure Slip Numbers . .

[old377guy]

Tony, if no one answers here just google the formula to plug in pitch, rpm, etc. I believe that this theoretical speed is measured against actual speed and generates a slip factor. Good luck. - Jeff

[Donskihp]

Mercury racing web site has a prop slip calculator Address ishttp://www.mercuryracing.com/propellers/propslipcalculator.php

[Ratickle]

Here it is as a link



http://www.mercuryracing.com/propell...calculator.php

[Ratickle]

Here is Marc's at BAM.....

With the formula above the calculator


http://www.go-fast.com/Prop_Slip_Calculator.htm

[Tony M]

Thank You ! I Think ? 83gps 30p @17 percent slip on a single guess it not to bad

[afr]

subscribed
a 26 pitch prop turning one time is pose to go 26 inches
if it only goes 13 inches thats 50 % slip but you can never go more then 26 inches
they are for an estimate IMO just entertainment really
there are no figures for cupping or for the amount of blades they say add one inch for 4 blades etc

so really i would have to put in 27 p for the extra blade and .25 for a 250 rpm cup .50 for a 500 rpm etc
and i worked in a proppeller shop 5 + years
Dad was really good at playing this guessing game so its more exsperance as to how to use the numbers then just throwing in the basic numbers

[Donskihp]

You ought to be able to do better than 17% on a single engine. I went from 16 down to 10% on my 2 steped hull Donzi. Brett from bblades helped me dial mine in with his propeller test program.

[Tony M]

You ought to be able to do better than 17% on a single engine. I went from 16 down to 10% on my 2 steped hull Donzi. Brett from bblades helped me dial mine in with his propeller test program.

Brett Got my slip down to 14.5 with full tank of fuel more than likely less after some burn off of fuel .

[jeffswav]

Try this site. http://www.rbbi.com/folders/prop/propcalc.htm
I have 9.8% slip at 74mph. Maybe you need a nose cone at speeds over 80? Maybe some prop work? What is your drive depth?