question about slip?

[troypolla]

I was doing some calculating, and this shows my slip to be 0.008310. This is in percent right? Or should I move the decimel over 2. But even then it would be less than 1% slip.
5800 rpm at wot
38mph
2.15gear

 

[Bondo]

Re: question about slip?

You're probably Off a Couple of decimal points.....

Anything from 10%,+ Under is considered Ideal.............

 

[troypolla]

Re: question about slip?

ok even if you do it by hand with these calculations
http://www.go-fast.com/Prop_Slip_Calculator.htm
you get 0.00809.

This was the site I used before
http://www.rbbi.com/folders/prop/propcalc.htm

15p
2.15 gear
5800rpm
38mph

 

[troypolla]

Re: question about slip?

verified with gps. forgot to add that.

 

[72SideWinderSS]

Re: question about slip?

If your prop is cupped, you need to add one inch to the actual pitch of the prop. i.e. 15p + 1 for cup = 16p
Running the numbers with 16p = 7%

 

[troypolla]

Re: question about slip?

Thats it. Thanks. It makes sense now.