Offshoreonly.com - Speed / Hp ?

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JUSTONCE

02-03-2003 01:16 PM

Speed / Hp ?

I can't find the sit that had the speed/ horsepwer/ hull drag coeficient(sp) equation. can anybody shoot me the link
Thanks in advance.
Martin

later

02-03-2003 01:21 PM

go-fast.com
Bam marine

JUSTONCE

02-03-2003 01:23 PM

thanks man.

GLH	02-03-2003 01:29 PM

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

Clay Washington

02-03-2003 01:42 PM

JUST ONCE,

A simple equation that I believe will get you close is:

New Speed = Old Speed times [ the squareroot of (New HP / Old HP) ]

or

New HP = Old HP times [ (New Speed / Old Speed) squared ]

Some people say that it should say "cubed" instead of "squared" but "squared" and "square root" will get you close.

Do the math! :D

JUSTONCE

02-03-2003 01:59 PM

Clay, thats pretty cool seems close!

HyperBaja

02-03-2003 02:11 PM

Calculating for that new blower :D

Mbam	02-03-2003 05:04 PM

Could be either something is wrong with the data, or that particular hull needs a different constant. The constants are not fixed in stone, but determined from experience with similar boats.

Picture changing to a Sportmaster or Labbed prop or something else that gives you 5-10 MPH with no change in weight or power, the constant will be different.

The best use of the calculator is to input the known weight, speed and power, then calculate a constant for that hull set up.

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