[C320-list] Boat Speed

[Karl Mielenhausen _/)]

James,

The spreadsheet I developed may be found here....
http://pages.suddenlink.net/kmielen/C320Docs/FuelEff.xls

Karl

On Mon, 06 Jul 2009 18:11:08 -0400, Jamie Pett <JPett at jp2architects.com>  
wrote:

> Paul / Mark / Everyone - I posted an earlier thread (errantly without a
> subject) regarding a tachometer anomaly, but also have the same question
> regarding speed , rpms, etc.  - my boat has a 27 Yanmar.
>
> I understand it is normative to cruise at 3100-3200 rpm, but cannot get
> the boat to go 6 kn. according to my gps at that rpm.  At 2800 I am
> going 5 - 5.2.  Others seem to report 6- 6.2 on this list all the time ?
> This is with reasonably clean bottom, full fuel, and about half tanks
> for water - 25 ga. or so.  Aren't the Yanmar's recommended to cruise at
> 3000 plus ?
>
> Would love to see the spreadsheet.
>
> I also have a fixed 3 blade prop.  My good friend has a 320 with a
> Perkins, and we 'drag raced' one day - his was clearly faster, with a 2
> blade - no idea why - same keel, etc.   His boat may weigh a bit less -
> mine has roller main, but I wouldn't think that some weight should do it
> under power, and tankage wasn't that different at the time ?
>
> James Pett
> Bella Luna
> #614

-- 
Karl Mielenhausen
Catalina 320 Hull 690
New Bern, NC

Join us August 7-9, 2009 at Marina Del Rey, CA for our annual Catalina  
320IA Regatta and Annual Meeting.