RPM and MPH for skiing

[mauleguy]

I have a 1996 Ski Brendella 19' boat with a Chevy 350, I am new to this kind of ski boat and was wondering if a different pitch propeller would be better for fuel economy. I ski at around 28-29mph and this boat is turning 3500 rpm at this speed, it has plenty of pulling power to get me out of the water. Is this pretty typical for this style of ski boat to turn that high of RPM for skiing, could I get better fuel economy if I was only turning 2800 RPM with a different propeller or would this mess up my idle speed for docking.

Thank you,

Greg

 

[Bondo]

Re: RPM and MPH for skiing

I have a 1996 Ski Brendella 19' boat with a Chevy 350, I am new to this kind of ski boat and was wondering if a different pitch propeller would be better for fuel economy. I ski at around 28-29mph and this boat is turning 3500 rpm at this speed, it has plenty of pulling power to get me out of the water. Is this pretty typical for this style of ski boat to turn that high of RPM for skiing, could I get better fuel economy if I was only turning 2800 RPM with a different propeller or would this mess up my idle speed for docking.

Thank you,

Greg

Ayuh,.... Welcome Aboard,...

3500 is 'bout midway of the power band, proppin' Up to lower the rpms, induces a luggin' condition,
All through the rpms...

It's quite conceivable, that you'd burn More fuel too...

I'd leave it be, 'n enjoy it...

 

[steelespike]

Re: RPM and MPH for skiing

If your boat is say 220 hp it will burn about 22 gph at wot. Of course less at reduced throttle.
The motor needs to reach close to or at the max rated wot rpm lightly loaded.You may be able to gain a little by selecting the prop that produces the most speed for a given throttle setting.
On a properly set up healthy boat the difference will likely be measured in tenths of a gallon.
A flow meter is a must if your going to try to figure things accurately.
There are props designed specifically for boats like yours,whether they would produce the best mileage
I don't know.

 

[jestor68]

Re: RPM and MPH for skiing

Inboard ski boats are geared and propped for their intended purpose. This generally does not include great fuel economy. 3500 rpm at 30 mph sounds about right to me.