Four Winns Volvo 3.0 - Cruising Prop?

Tailwinns

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Aug 27, 2015
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I know I might get hammered for dragging up an old thread but I have the exact same boat, am having the exact same issue and this is the only place I have seen it addressed. I bought a 19p 4 blade Solas prop from this site and love the hole shot and ability to tow a skier but would also like to be able to swap it out on days we want to cruise and add a bit to the top end.

I am ready to drop the $120 or so bucks on a 23p and take a gamble. My only question is 4 blade or 3?
 

steelespike

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Apr 26, 2002
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19,069
I don't think you will like the 23.And neither will your motor. What is the present light load wot rpm and gps speed.
Tell us about your Four Winns. year,length,dry weight.
Your motor is working very hard like a car pulling a trailer up a never ending hill.
As you increase pitch its like getting closer to over drive.I think a 23 will be like over drive.
If you want more speed for cruising maybe a 18" Hustler 3 blade.
We need your present numbers before any change.
 

Tailwinns

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Aug 27, 2015
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2006 Four Winns 180 Horizon 3.0 Volvo Penta. Dry weight 2400lbs.

With the stock 3 blade 21p 14.3 Volvo prop I am easily over the 4600rpm max and with 400lbs worth of people (2 adults and one child) 33 to 34mph was a struggle on a fairly calm lake (GPS verified). With the 4 blade 19p 31 to 32mph at 4600.

I really need to get out by myself on a calm day and nail those numbers down. I just know I still have a good bit of throttle left with either prop. Hadn't considered a larger diameter prop.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Jul 23, 2011
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I would verify your tach with a shop tach as well. your RPM numbers sound high for the speed
 

steelespike

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Apr 26, 2002
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19,069
I would verify your tach with a shop tach as well. your RPM numbers sound high for the speed
Agreed, 21" @ 4600 34 mph = 25% slip. 12% is more typical. 19" 4600= 22%
When slip is not accurate the tach is usually the culprit.And often is in error. Also suspect that rpm is the same for 2 different props.
 

Tailwinns

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Aug 27, 2015
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Agreed, 21" @ 4600 34 mph = 25% slip. 12% is more typical. 19" 4600= 22%
When slip is not accurate the tach is usually the culprit.And often is in error. Also suspect that rpm is the same for 2 different props.

Actually the RPM is the same based on me limiting throttle. I could have easily hit 5k on the tach with both props. Two items on my list are verifying tach function and retesting both props on a calm day by myself.
 

fishrdan

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Jan 25, 2008
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6,989
Hadn't considered a larger diameter prop.

Probably for the best as "large" diameter props are meant for large heavy boats, which you don't have. I'd stick with 14"(+) diameter props.

I agree with the others that something seems off with the numbers, speed - RPM - prop pitch.
 
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